Characterization of Turkish coals: a nationwide perspective

International Journal of Coal Geology 60 (2004) 85 – 115 www.elsevier.com/locate/ijcoalgeo

Characterization of Turkish coals: a nationwide perspective

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Curtis A. Palmer a,*, Ertem Tuncalı b, Kristen O. Dennen a, Timothy C. Coburn c, Robert B. Finkelman a b

a U.S. Geological Survey, Mail Stop 956, Reston, VA 20192, USA Directorate of Mineral Research and Exploration 06520, Ankara, Turkey c Abilene Christian University, Abilene, TX 79699, USA

Received 25 March 2004; accepted 4 May 2004 Available online 28 October 2004

Abstract The U.S. Geological Survey (USGS) and the Turkish General Directorate of Mineral Research and Exploration (Maden Tetkik ve Arama Genel Mu¨du¨rlu¨gu¨, MTA) are working together to provide a better understanding of the chemical properties of Turkish coals from major Turkish lignite producing areas. The coals in Turkey are generally low rank (lignite or subbituminous) formed in several different depositional environments at different geologic times and have differing chemical properties. Eocene coals are limited to northern Turkey; Oligocene coals, found in the Thrace Basins of northwestern Turkey, are intercalated with marine sediments; Miocene coals are generally located in Western Turkey. The coal deposits, which have limnic characteristics, have relatively abundant reserves. Pliocene – Pleistocene coals are found in the eastern part of Turkey. Most of these coals have low calorific values, high moisture, and high ash contents. Analysis of 143 coal channel samples (most are lignite and subbituminous in rank, but a few are bituminous and one is anthracitic in rank) has been completed for up to 54 elements and other coal properties using a variety of analytical techniques, including inductively coupled plasma emission and mass spectrometry, instrumental neutron activation analysis, and various single element techniques and ASTM standard procedures. Many of these coals have elemental concentrations similar to U.S. lignites found in the Gulf Coast and Fort Union regions. However, maximum or mean concentrations of B, Cr, Cs, Ni, As, Br, Sb, Cs, and U in Turkey are higher than the corresponding maximum or mean values found in either the Fort Union or Gulf Coast regions. D 2004 Elsevier B.V. All rights reserved. Keywords: Coal; Coal geology; Trace elements; Turkey; Inductively coupled atomic emission spectroscopy

1. Introduction $

Supplemental material associated with this article can be found in the on-line version at doi:10.1016/j.coal.2004.05.001. * Corresponding author. Tel.: +1-703-648-6185; fax: +1-703648-6419. E-mail address: [email protected] (C.A. Palmer). 0166-5162/$ - see front matter D 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.coal.2004.05.001

Until recently, the Turkish economy was growing rapidly and electrical energy demand was increasing approximately 8% per year on average. Total installed electric capacity reached 26,200 MW by the end of 2000. Over half of this electric capacity (approximately

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15,500 MW) is thermal energy which is derived from burning coal and natural gas, and the remaining capacity (10,500 MW) comes from other sources primarily hydroelectric with some geothermal and wind energy. Electricity generation more than doubled from 1990 to 2000, but Turkey still imported nearly 20 times as much electricity in 2000 as 1990 due to the high demand (Lynch, 2003). Coal is clearly important to the Turkish economy. Tuncalı et al. (2002) and Lynch (2003) report that Turkish lignite reserves are estimated to be over 8 billion metric tons, ranking Turkey seventh largest in the world. Some of these reserves are probably subbituminous in rank. Lynch (2003) reports that 7% of the low rank coals have heat capacities of over 3000 calories per gram (5400 Btu/lb). Data derived from Tuncalı et al. (2002) suggest that up to 15% of the total coal reserves in Turkey are of subbituminous rank or higher. Ash and sulfur data from this study can be used to show that the average rank for coals with 3000 calories per gram would be near the low end of subbituminous ranking using ASTM (2003) standards. In addition, Turkey has 1.1 billion tons of hard coal reserves with heat capacities over 5700 calories per gram (10260 Btu/lb). Although reserves (especially of lignite) are ‘‘widespread and plentiful’’ (Lynch, 2003), Turkey imports 8.5 million tons of hard coal a year. Until recently, little was known of the quality of Turkish coals. The U.S. Geological Survey (USGS) and the Turkish General Directorate of Mineral Research and Exploration (Maden Tetkik ve Arama Genel Mu¨du¨rlu¨gu¨, MTA) are working together to provide a better understanding of the chemical properties of coals from major Turkish lignite producing areas. This study is part of the ‘‘Technological and Chemical Properties of Turkish Lignites Inventory’’ project being conducted by the MTA General Directorate to provide Turkey with information on its coals (Tuncalı et al., 2002) and the World Coal Quality Inventory (WoCQI) project being conducted by the USGS to look at the coal quality worldwide (Finkelman et al., 2001). This study is intended to provide a snapshot of coal quality at a single point in time. Therefore, individual samples were obtained from as many working mines as possible with only one sample per coalfield for a total of 143 samples.

Turkey is traditionally divided into seven geographic regions: the Marmara Region in northwestern Turkey, the Aegean Region in southwestern Turkey, the Black Sea Region in north central Turkey, the Central Anatolian region in central Turkey, the Mediterranean Region in south central Turkey, the Eastern Anatolian region in northeastern Turkey, and the Southeastern Anatolian region in southeastern Turkey. The Marmara Region can be further broken up by the Marmara Sea into a North Marmara Region and a South Marmara Region, making a total of eight regions. These regions are shown in Fig. 1. In this paper, trace element data are examined for samples collected from 143 different coalfields. Palmer et al. (1999) previously discussed 71 of these samples taken from the two Marmara regions and the Aegean Region of Western Turkey. The discussion in this paper encompasses these samples and additional samples from the same regions, as well as samples from regions of Eastern Turkey (except the Southeastern Anatolian region). For some of the statistical analysis described here, the Central and Eastern Anatolian regions are combined because of the small number of samples. For these purposes, this region will be called the Combined Anatolian region. This is the first comprehensive, nationwide study of trace elements in Turkish coals. Coal analysis in Turkey has been generally limited to proximate, ultimate, and petrographic analysis. Trace elements analyses were reported by Ayanog˘lu and Gunduz (1978a,b,c) using instrumental neutron activation analysis. Recently, there has been more interest in trace elements in Turkish coal (Karayigit, et al., 1999, 2000a,b,c; Palmer et al., 1999; Querol et al., 1997, 1999). These papers deal primarily with the composition of Turkish coals from specific regions, but Karayigit et al. (2000a) report on 10 feed coals for powerplants from four different regions of Turkey. Trace element analyses are important in terms of environmental, economic, by-product, and technological behavior of coals and their effects on human health. Although a single sample cannot represent a coalfield, samples collected from different coalfields within a basin can provide information on variability. The data from this study provide nationwide and regional baselines for elemental

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Fig. 1. Map of Turkey showing geographic regions and sample locations.

concentrations that can be used for comparison with other more detailed studies within individual coalfields.

2. Geologic setting 2.1. Paleogeography Lu¨ttig et al. (1976) first prepared a paleogeographic atlas of Turkey covering a time interval of Oligocene to Pleistocene. Lignite exploration studies that are especially concentrated in Neogene and Quaternary nonmarine deposits were carried out in Turkey. More than 1000 drillings were made, with depths not exceeding 200 m, in localities of likely lignite production within an area of approximately 500,000 km2. More than half of these drill holes are located in Elbistan Basin. During these exploration studies, biostratigraphic data on terrestrial Neogene deposits of Turkey were obtained, and these data formed the basis of paleogeographic atlas constructions. Complementary field studies in brackish water, as well as marine Neogene deposits of Turkey not studied during lignite exploration, were completed in 1970 – 1971

and seven paleogeographic maps of 1/1,500,000 scale were constructed (Lu¨ttig et al., 1976). A second paleogeographic study on Turkey, carried ¨ BITAK-Global Tectonic Research Unit, was out by TU published as 19 maps titled ‘‘Triassic – Miocene Paleogeographic Atlas of Turkey’’ (Go¨ru¨r et al., 1998a). A 1/2,000,000 scaled geological map of Turkey prepared by Bingo¨l (1998) was the basis for construction of paleogeographic maps. Summary information on geographic location and lithofacies properties of the coal deposits compiled from Lu¨ttig et al. (1976) and Go¨ru¨r et al. (1998a) are presented here for Oligocene – Pleistocene and late Eocene –Miocene periods, respectively. Summary information about type, age, and depositional environments of some important Turkish coal and peat deposits are given in Table 1. Data on coal type and depositional environments are presented in this study and depositional ages of some coal deposits are revised. According to Go¨ru¨r et al. (1998b), Upper Eocene (Priabonian) rocks are present mostly in the Thrace Basin and central part of the eastern Black Sea Mountains in North Anatolia. These deposits contain carbonates and clastics in the Thrace Basin. Carbonates usually parallel the Istranca Massif along the southern

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Table 1 Coal field locations, ages, coal type (petrographically), and their environments in Turkey Series

Age (Ma)

Coal type

Environment

Subbituminous Neogene

Paleogene

Pliocene

1.7

Miocene

5.4 23

Oligocene

37

Eocene

55

Coal type

Environment

Lignite

Bursa – Keles – Harmanalan, Konya – SedisSehir – BeyavsSar, Konya – Ilgın – Haremiko¨y

Limnic

Adana – Tufanbeyli, Adıyaman – Go¨lbasSı, AfsSin – Elbistan, Erzurum – Horasan – AlicSeyrek, Erzurum – ˙Ispir, Sivas – Kangal

Fluvial, Limnic, continental with volcanic intercalations

Aydın – SSahinali, Aydın – So¨ke, Balıkesir – Dursunbey – Odako¨y, Bolu – Go¨ynu¨k – Himmetog˘lu, Bursa – Orhaneli – Burmu, CSanakkale – Yenice – CSırpılar, CSorum – Alpagut – Dodurga, Denizli – Kale – Kurbalık, Erzurum – AsSkale – Ku¨ku¨rtlu¨, Erzurum – Oltu – Balkaya and Su¨tkans, EskisSehir – MıhalıcScık – Koyunag˘ılı, ˙IcSel – Namrun – CSamlıyayla, Karaman – Ermenek, Ku¨tahya – Seyito¨mer and TuncSbilek, Manisa – Soma – (Eynez, Darkale, IsSıklardere, DenisS I – II), Manisa – Go¨rdes – CSıtak, Mug˘la – Milas – (Alakilise, CSakıralan) Edirne – Uzunko¨pru¨ – Harmanlı, Tekirdag˘ – Saray – Edirko¨y Bolu – Mengen – SalıPazarı Yozgat – Sorgun

Limnic, continental with volcanic intercalations

Balıkesir – Dursunbey – Hamzacık and CSakırca, Mug˘la – Milas – (Ekizko¨y, Sekko¨y, Hu¨samlar), Mug˘la – Yatag˘an – (Tınaz, Bag˘yaka, Eskihisar, Bayır)

Limnic

Fluvial, Deltaic

Tekirdag˘ – Malkara – AhmetpasSa, Tekirdag˘ – Hasko¨y – ˙Ibrice

Fluvial, Deltaic

Limnic

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System

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border of the basin, while clastic facies are observed in the inner parts of the basin. Upper Eocene is dominantly represented by volcanic, volcanoclastic, and plutonic rocks in the central part of the eastern Black Sea Mountains, while sedimentary strata crop out in limited areas around Samsun – Sinop and Boyabat basin. Lignites of Boyabat basin occur as intercalations within marls, cross-bedded conglomerates, and sandstones. The Upper Eocene deposits crop out in Central Anatolia in C¸ankırı, Kırıkkale, Ulukıs¸la, Refahiye, Yıldızeli, and around Klrıs¸ehir Kaman. The Upper Eocene sequence in the Refahiye basin is composed of shallow marine terrestrial conglomerate, sandstone, shale, and limestone alternations with plant remains and coal seams. Upper Eocene deposits in southeast Anatolia crop out in some parts of the western and central Taurus Mountains. They are composed of shallow marine conglomerate, sandstone, shale, marl, and limestone in Denizli – Eg˘ridir Lake and around Bey Mountains. Upper Eocene deposits are represented by shallow to deep marine clastic and carbonate facies in East Anatolia (including eastern Taurus) and shallow to relatively deep marine facies in the Arabian Platform. According to Lu¨ttig et al. (1976), limnic-fluvial deposits covered the whole Thrace Basin and southeast Anatolia (Mug˘la – Denizli – Burdur corridor) during early-middle Oligocene. Thracian coals were deposited within these limnic-fluvial deposits and are considered to be early-middle Oligocene in age. Terrestrialfluvial deposits of early Oligocene were present in Central Anatolia (west and south of Ankara) and partly in East Anatolia (around Erzincan). Littoral and neritic facies deposits were present south of Burdur Lake, at the tip of southwest Anatolia, east of Adana (Ceyhan plain), Antalya, Gaziantep, and Urfa areas. During the late Oligocene, lacustrine-fluvial and molasse facies characteristics were present in the southwestern end of West Anatolia (Mug˘la – Denizli – Burdur Lake corridor), and littoral and neritic facies were dominant west of Antalya and East Anatolia (an area extending from east of Mus¸ to Iran). Marine intercalated Red Bed molasse extends on an area covering almost all of the Central Anatolia, Sivas – Erzincan, and Erzurum –Kars– Ag˘rl areas. During the early Miocene, littoral and neritic facies deposits covered the entire Mediterranean Region, the southern part of Aegean Region, and an area in East

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Anatolia including south of Sivas – Erzincan – Erzurum – Kars and Lake Van at north and Gaziantep – Urfa – Diyarbakır at the south. Thin, local coal seams are present within this area around and the north of Silifke (Mersin), southeast of Sivas, and around Erzincan. Within these extensive shallow marine deposits, brackish water lithofacies are present around Sivas and west of Diyarbakır, while marine-intercalated Red Bed molasse extends around C¸ankırı, Ankara –Bala, southeast of Gu¨mu¨sSwhane, and in small areas northeast of Erzincan. Lacustrine deposits with local coal seams are present in areas north of C¸orum (Dodurga, Osmancık, Zambal, etc.). Terrestrial deposits of early Miocene age are generally observed in north, west, and Central Anatolia, while marine deposits are observed in the Taurus Mountains and Arabian Platform. Lower Miocene deposits from Thrace Basin and around Kastamonu consist of conglomerate, sandstone, and shale with local dolomitic limestone, tuff, and coal seams. The thickness of these deposits, which bear ostracoda, fish, and plant remains, is as great as 3000 m in Thrace Basin. Similar deposits around Kastamonu include coal-bearing marls. Lower Miocene deposits in West Anatolia are usually found in NE – SW trending depositional basins within a graben system. The depositional sequence starts with conglomerate, sandstone, and shale and continues upward with marl and limestone. The deposits include plant remains, mammalian fossils, and local lignites along with alkaline and subalkaline volcanic rock interlayers. Lower Miocene deposits have limited extension in Central Anatolia. They occur in the Galatian Massif with basic volcanic intercalations and in Kızılırmak Valley (between Bala and C¸ankırı) as fluvial sandstone, siltstone, and claystone layers. During the middle Miocene, West Anatolia (Aegean region and southwestern end of Thrace) was an area where limnic, limnic-fluvial, and partly volcanic intercalated limnic-fluvial deposits developed. Similar deposits also extend to the south and southwest of Ankara, between Ankara – C¸orum, and around Konya where important coal deposits of Turkey are located today. Littoral and neritic facies deposits extend into the Mediterranean region, while marine-intercalated Red Bed molasse deposits extend in a corridor bounded by Sivas – Erzincan –Erzurum at the north and Malatya – Bingo¨l and the northern

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part of Lake Van at the south. Terrestrial-fluvial deposits are present in an area between Diyarbakır –Siirt. The upper Miocene is dominantly represented by acid volcanic and volcanoclastic rocks. In Central Anatolia, however, it is an interval of intercalated fluvial, limnic, and volcanic deposits. Coal seams are present locally in these deposits. Terrestrial-fluvial deposits developed in a wide area around Diyarbakır –Siirt, west of Bursa, east of I˙zmir, and around the Menderes river. Upper Miocene is interpreted as coastal, shelf, and continental slope facies in the Taurus Mountains and East Anatolia. Coastal facies are composed of clastic and carbonate deposits with ostracoda, gastropoda, echinoderm, pelecypoda, foraminifera, spore, pollen, plant remains, and local coal seams (around Karaman – Ermenek). Upper Miocene (Tortonian –Messinian) deposits representing fluvial, lacustrine, and coastal environments occur in the Thrace Basin in and around the Marmara Sea and along the Black Sea coast. Upper Miocene deposits are extensive in West Anatolia in the Bigadic¸ (Balıkesir), Go¨rdes (Manisa), UsSak, Tire (I˙zmir), Denizli, and Mug˘la (Yatag˘an) areas. They are deposited in east – west extending grabens and composed of interfingering lacustrine and fluvial deposits. Lacustrine deposits generally are composed of marl and limestone with intercalations of detritus, evaporite, lignite, and volcanogenic rocks. Fluvial deposits are composed of marl, sandstone, shale, and tuff. They also contain sporadic evaporite and coal seams. Upper Miocene deposits are widespread in Central Anatolia. They are composed of limnic and fluvial conglomerate, sandstone, marl, evaporate, and tuffs in the Haymana –Polatlı basin. Similar deposits in the Salt Lake basin, Turkey, consist of interfingering fluvial, clastic, volcanic, and limnic marl with gypsum and clayey limestone. Upper Miocene deposits in the Sivas Basin contain coarse grained, red sandstone and gypsum. They are characterized by local evaporatebearing marl and shale layers in the Yozgat –Yerko¨y area. Upper Miocene deposits, characterized by depositional environments changing from shelf to fluviallacustrine environments, are composed of conglomerate and sandstone in the west-central Taurus region. Contemporaneous deposits in East Anatolia are characterized by limnic and fluvial deposits with volcanic

and volcanoclastic intercalations. Upper Miocene deposits usually developed in terrestrial-coastal facies in southeast Anatolia and they occasionally occur together with basaltic volcanics. Well-developed outcrops of terrestrial deposits between Gaziantep and Siirt consist of red conglomerates including freshwater fossils, sandstone, shale, and marl. Coastal facies are usually present around Hatay. They are characterized by conglomerate, sandstone, shale, marl, limestone, and evaporates and are overlain by fluvial and lacustrine deposits. The Pliocene is characterized by limnic-fluvial and volcanic intercalated limnic deposits in a corridor extending from south of Istranca Massif (until Tekirdagˇ) to southwest of Thrace, south of Marmara Region (Bura –Keles), wide areas in Central Anatolia (around Konya, Beys¸ ehir, and Seydis¸ ehir), around C¸ankırı and in small areas north of it, around and south of Sivas (Kangal), around the Adana and Toros areas (Tufanbeyli) in the Mediterranean region, north of Kahraman MarasS (Elbistan is the biggest coal deposit of Turkey with 3.5 billion tons), and around Erzincan and Erzurum (Horasan –Alic¸eyrek, Hınıs – Zırnak) in East Anatolia. Terrestrial-fluvial and limnic intercalated terrestrial deposits are present in an area extending from Us¸ak and Afyon to the north of Konya. Peats were developed in limnic-fluvial and limnic facies of late Pleistocene in areas (Du¨zce, Yenic¸agˇa, Niksar, Go¨le, Ardahan, etc.) with continuous sedimentation since the Pliocene. Peats also were deposited in lakes of mountainous areas in East Anatolia (MusS, Hakkari Yu¨ksekoba) between intervals of volcanic activity. Recent evidence has redefined the age of coal formation. Differences between ages of coal formation determined by Lu¨ttig et al. (1976) and Go¨ru¨r et al. (1998b) can be summarized as follows: Eocene coal deposits, mined today, were not mentioned in Go¨ru¨r et al.’s (1998b) study. No coal symbol is present on the Eocene outcrop map because Go¨ru¨r et al. (1998b) considered that most of the important Turkish coal deposits were formed during late Miocene, whereas Lu¨ttig et al. (1976) considered that most of the important Turkish coals were formed during middle Miocene. However, biostratigraphic studies carried out especially on mammals (Bruijn et. al., 1992, 1993, 1999; Bruijn and Sarac¸, 1991, 1992) indicated that the main age of coal formation in Turkey is early

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Miocene. The age of Thracian coals is early-middle Oligocene based on data from mammalian fossils (Lebku¨chner, 1974; Sarac, 1987, 2000, personal com¨ nay-Bayraktar, 1989; Go¨kmen et. al., munication; U 1993) and palynological data (Batı, 1996). 2.2. Coal resources In Turkey, terrestrial Tertiary deposits with coalbearing potential cover approximately 110,000 km2. This area has been examined by the Turkish General Directorate of Mineral Research and Exploration, and an area of 41,723 km2 that appeared to be most promising for coal mining has been geologically mapped (in scales of 1/25,000 and 1/10,000) and checked by drill holes with a total length of more than 1,212,000 m. Drill-hole intervals range between 50 and 2650 m. After detailed studies, the extent of the coal-bearing formations was determined to be about 1473.9 km2. The thickness of coal seams ranges between 0.05 and 87.0 m, with a maximum depth of coal seam from surface being 828 m (Tuncalı and Ocakog˘lu, 1995; Go¨kmen et al., 1993). Based on these studies, a resource of 8.3 billion tons of low rank coal reserves was determined (Demirok and Uc¸akc¸log˘lu, 1993). The amount of proved recoverable reserves is estimated to be 3.9 billion tons based on feasibility studies of 43 of the most important coalfields. Of these reserves, 68.5% are suitable for surface mining. Annual coal production in Turkey reached 72.6 million tons (90% from state run mines) in 2001. Turkey also imports about 8 million tons of coal (mostly hard coal; EIA, 2003). Most of Turkey’s coal (54 million tons) supplies coal-fired powerplants which produced 38,400 GW h or 31.2% of the electrical power for Turkey. The rest is consumed in industrial (20 million tons including production of coke) and domestic uses (8 million tons) (Black Sea Economic Business Council, personal communication, 2003). Regional distribution of coal reserves and other parameters such as surface area, thickness, depth, total length of drill holes, etc., are given in Table 2.

3. Samples As part of two larger studies, one to assess the amounts and chemical properties of Turkish coal

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reserves (Tuncalı et al., 2002) and the other to obtain information on coal quality for the USGS World Coal Quality Inventory (Finkelman et al., 2001), a total of 143 channel samples (including 71 reported on earlier by Palmer et al., 1999) were collected and analyzed. One sample per coalfield was collected in order to obtain data from as many areas as possible. Each sample was obtained from a working mine. Partings thicker than about 50 cm were excluded from the sample collected because this material is not mined. Coal seams over 4 m in thickness were sampled in 2 –3 m benches and then recombined as composite samples using weighted averages (by thickness) of each bench. For statistical evaluation, the coal samples are subdivided into geographic regions. The number of samples analyzed from each region is given in Table 3. Fig. 1 shows the sample locations. There are no samples from the Southwest Anatolian region. There are only four samples from the Central Anatolian region and five samples from the Eastern Anatolian region. For certain statistical purposes, these two adjacent regions have been combined to form a single ‘‘Combined Anatolia’’ geographic area represented by a total of nine samples. The Turkish government also determines resources according to geographic regions. Unfortunately, since provinces often cross geographic regional boundaries and data from each province are compiled in the capital of that province, the data are assigned to the geographic region of that capital, which may not be the geographic region of the mine. Because the sample data discussed here will be used for various applications (e.g., the Web-based geologic information system application GEODE at http://geode.usgs. gov), they are reported in terms of their actual geographic regions, except for the resource data contained in Table 2.

4. Experimental Each of the 143 samples was characterized by various coal-testing procedures and analyzed for major and trace elements by a range of multielementand element-specific techniques. Volatile matter, fixed carbon, and gross and net calorific values are determined using ASTM (2003). Sulfur is analyzed

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Table 2 Regional distribution of reserves and some properties of Turkish coal Region

Surface area (km2)

Depth (m)

Number of holes with coal

to south 219.80 0.10 – 5.10 161.19 0.05 – 39.75 279.69 0.20 – 57.00

0.0 – 331.6 0.0 – 828.0 0.0 – 601.0

794 851 1955

Central Turkey north to south Black Sea 42.77 0.35 – 12.60 Central Anatolia 558.90 0.20 – 27.30 Mediterranean 25.28 0.60 – 18.20

0.0 – 605.0 0.0 – 522.6 0.0 – 378.0

Eastern Turkey north to south East Anatolia 184.85 0.10 – 26.05 Southeast Anatolia 1.50 3.90 – 87.00 Total 1473.97 0.05 – 87.00

0.0 – 800.0 0.0 – 150.0 0.0 – 828.0

Western Turkey north North Marmara South Marmara Aegean

Coal thickness (max – min) (m)

Number of holes without coal

Total number of holes

Distance between holes (m)

Total drilling length (m)

Total reserves million tons

301 308 396

1095 1159 2351

150 – 1200 100 – 1500 50 – 1950

98,702.42 235,213.94 361,585.83

525,201 299,629 2,013,651

272 1036 52

98 342 33

370 1378 85

50 – 1000 50 – 1500 100 – 1500

105,998.77 168,919.45 13,792.9

215,37 1,324,864 362,606

1271 22 6253

143 6 1627

1414 28 7880

65 – 2650 200 – 800 50 – 2650

225,781.3 2163.6 1,212,158.21

3,579,957 53,094 8,374,372

Data from Go¨kmen et al. (1993) and Demirok and Uc¸akc¸log˘lu (1993).

by a LECO1 sulfur analyzer using both the ash and the whole coal, and the combustible sulfur is determined by difference. Samples are ashed at 815 jC (in the MTA laboratories in Turkey using ISO standard 1171; ISO, 1997) and at 525 jC (in the USGS laboratories in the United States using standard USGS procedures: Bullock et al., 2002). The lower temperature of USGS ash is recommended for trace element determinations using inductively coupled plasma-atomic emission spectrometry (ICPAES) and inductively coupled plasma-mass spectrometry (ICP-MS). ICP-AES involved both a sinter digestion to determine the major components of Si, Al, Ca, Mg, K, Fe, Ti, P, and the trace elements B, Ba, and Zr and an acid digestion to determine the concentrations of Na, Be, Co, Cr, Cu, Li, Mn, Ni, Sc, Sr, Th, V, Y, and Zn (Briggs, 1997). ICP-MS involved the same acid digestion solution as the ICPAES to determine As, Au, Cd, Cs, Ga, Ge, Mo, Nb, Pb, Rb, Sb, Sn, TI, and U as described by Meier (1997). Mercury and Se are determined on whole coals by cold-vapor atomic absorption analysis and hydride generation atomic absorption, respectively, using procedures described by O’Leary (1997). For 1

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selected whole coal samples, instrumental neutron activation analysis (INAA) is used to determine K, Fe, Na, As, Au, Ba, Br, Co, Cr, Cs, Hf, Ni, Rb, Sb, Sc, Se, Sr, Ta, Th, U, W, Zn, La, Ce, Nd, Sm, Eu, Tb, Yb, and Lu using procedures described by Palmer (1997). The agreement of the INAA results on the whole coal samples and the ICP-AES and ICP-MS results on the ash (for those elements that are determined in common) increased the confidence in the values obtained. Because only selected samples were evaluated using INAA, values obtained via ICP-AES or ICP-MS were preferentially assigned to elements which are determined using both approaches. INAA results are used when determinations are below the detection limit by the ICP techniques or where the data are clearly better. The data were statistically examined by applying various descriptive and inferential methods to both the total data set and the data sets representing the individual regions. For each major element, trace element, or parameter (ash, calorific value, moisture, etc.), similarities and differences are determined for all regions using two separate statistical investigations. First, each region is considered separately even though the Central Anatolia had only four samples and the Eastern Anatolia had only five samples. Second, differences between regions

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are determined using the Combined Anatolian region instead of the individual Central and Eastern Anatolian regions. For several samples, one or more elements were recorded as having values below a detection limit, such as < 0.001. In order to include information from these measurements in the statistical analysis, these ‘‘less than’’ values were set to 0.7 times the ‘‘less than’’ amount (e.g., 0.7  0.001). However, elements were not statistically analyzed if 25% or more of the recorded measurements were ‘‘less than’’ values (Bragg et al., 1998). In addition, weighted averages of selected elements were determined for the largest 26 mines which represent over 80% of Turkish coal production. Box and whisker plots (Ott and Longnecker, 2001) were first constructed for many standard coal parameters and for most elements. Separate plots were constructed for each region, the Combined Anatolian region, and for the entire country. These plots indicate the 10th and 90th percentiles of the respective quantity, the 25th and 75th percentiles, and the median. Outliers, which for this paper are defined to be values that fall beyond either the 10th or 90th percentiles, are also identified. The box and whisker plots yield important information about the statistical distribution of each respective element and coal parameter and facilitate preliminary understanding about the differences among regions on the basis of the individual quantities. These plots were generated using SigmaPlotR Version 8.0. Detailed descriptions of the statistics used to generate these plots can be found in the user’s guide (SigmaPlot, 2002). Two additional box and whisker plots were constructed for elements represented by ‘‘less than’’ values to check the effect of applying the ‘‘0.7 multiplier’’ rule described above. In the first case, all the ‘‘less than’’ values were replaced by the actual lower limits recorded in the database (e.g., < 0.001 was replaced by 0.001). In the second case, all the ‘‘less than’’ values were replaced by zero. For each element involved, these additional box plots were overlain to determine how the percentile limits were affected. On the basis of this assessment, one can see how the inclusion of less than values affects the median and various percentiles shown in the box and whisker plots. Differences among regions were formally examined using a nonparametric (NP) approach to analysis

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of variance (ANOVA). The nonparametric approach, referred to as the Kruskal – Wallis test (Conover, 1999), was selected for three reasons: (1) the relatively small numbers of samples per region; (2) the non-normality of the distributions of the sample values of the individual elements and coal parameters observed in the box and whisker plots; and (3) the low likelihood of satisfying the normality assumption required of conventional (parametric) statistical approaches through algebraic transformation of the data. A separate statistical analysis was conducted for each element or coal parameter derived from standard coal chemical analysis using the following procedure. The 143 values representing all the measured concentrations of a specified quantity were ranked from low to high. The lowest recorded concentration was assigned a rank value2 of 1 and the highest concentration was assigned a rank value of 143. The 143 samples were then grouped according to their geographic regions, and the mean of rank values of concentration assigned to the samples associated with each region was calculated. Differences in mean rank values of concentration associated with all unique pairs of regions were then computed, along with the 95% confidence limits for each difference. Pairs of regions were determined to be significantly different at the 0.05 level of statistical significance if the 95% confidence interval on the difference in their mean rank values of concentration did not encompass a value of 0. This decision criterion is tantamount to computing the protected least significant difference (LSD), a well-known rendition of the t-test (Miller and Miller, 1984), between mean rank value values of concentration. In comparison to other methods (e.g., the Tukey procedure; Miller and Miller, 1984) for evaluating the significance of differences between means, the LSD approach was deemed to be most appropriate for this particular situation. Petrographic studies included in this paper were conducted in Turkey using procedures described by Tuncalı et al. (2002). Maceral identification and vitrinite reflectance measurements were made and the results were used to determine rank of the coals. 2 The term ‘‘rank value’’ shall be used throughout the text instead of the more classical term ‘‘rank’’ for statistical rankings so that it will not be confused with the coal term ‘‘rank’’ which indicates the degree of coalification of coal samples.

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Regions in Turkey

Summary

USA regions

Region

North Marmara

South Marmara

Aegean

Black Sea

Mediterranean

Central Anatolia

East Anatolia

Combined Anatolia

Total: all of Turkey

Gulf Coast USA

Fort Union USA

Number

N = 28

N = 16

N = 64

N = 13

N = 13

N=4

N=5

N=9

N = 143

N = 142

N = 205

Moisture as-received (wt.%) m F s[n] 31 F 11 25 F 9 Median 32 23 (Range) (11 – 47) (6.1 – 40)

25 F 10 25 (3.2 – 41)

16 F 9.5 15 (5.1 – 39)

29 F 12 24 (15 – 58)

22 F 22 18 (3.4 – 49)

31 F 21 28 (1.2 – 52)

27 F 20 28 (1.2 – 52)

26 F 12 25 (1.2 – 58)

34 F 11[111] 35 (4.4 – 57)

38 F 5.3[190] 39 (26 – 57)

Residual moisture (wt.%) m F s[n] 11 F 2.5 Median 9.9 (Range) (6.6 – 16)

6.6 F 2.5 6.2 (1.6 – 10)

7.7 F 3.0 8.1 (1.2 – 14)

5.5 F 1.9 5.6 (3.0 – 8.7)

11 F 2.0 11 (8.1 – 14)

6.6 F 5.2 5.4 (2.3 – 13)

6.4 F 3.6 5.8 (0.66 – 11)

6.5 F 4.1 7.2 (0.66 – 13)

8.2 F 3.2 8.4 (0.66 – 16)

ND ND ND

ND ND ND

Remnant moisture (wt.%) m F s[n] 8.1 F 0.98 Median 8.2 (Range) (6.4 – 11)

6.7 F 2.1 7.0 (1.8 – 10)

7.3 F 2.0 7.8 (1.6 – 10)

6.2 F 1.6 6.2 (3.9 – 9.4)

8.6 F 2.4 8.6 (2.4 – 12)

6.9 F 4.3 6.9 (2.8 – 11)

7.4 F 3.4 8.6 (1.5 – 9.7)

7.2 F 3.6 8.6 (1.5 – 11)

7.4 F 2.1 7.8 (1.5 – 12)

ND ND ND

ND ND ND

21.4 F 9.9 19.9 (5.8 – 56.1)

19.5 F 10.0 18.7 (5.2 – 42.5)

19.0 F 9.3 17.6 (6.9 – 42.8)

27.4 F 19.5 26.9 (8.3 – 47.3)

26.0 F 11.2 24.2 (16.1 – 43.5)

26.6 F 14.4 24.2 (8.3 – 47.3)

20.4 F 10.0 18.3 (5.2 – 56.1)

Ash 750 jC 12 F 5.3[111] 12 (2.8 – 30)

8.6 F 4.0[190] 7.4 (3.5 – 25)

27 F 17 24 (5.2 – 69)

33 F 17 32 (16 – 52)

40 F 12 33 (31 – 62)

37 F 15[4.0] 33 (16 – 62)

28 F 12 26 (5.2 – 69)

18 F 7.1 17 (5.2 – 33)

12 F 5.1 10 (5.0 – 32)

28.2 F 5.3 31.2 (19.5 – 33.8)

25.7 F 3.0 27.0 (21.3 – 27.5)

24.8 F 5.5 21.0 (20.2 – 31.1)

25.2 F 4.3 26.6 (20.2 – 31.1)

27.4 F 5.3 27.3 (8.9 – 43.8)

28 F 5.4[111] 28 (18 – 46)

25 F 2.5[190] 25 (20 – 40)

Element

Ash 815 jC [except as noted] (wt.%) m F s[n] 16.2 F 6.3 22.2 F 11.6 Median 15.0 17.9 (Range) (7.3 – 30.0) (7.5 – 39.1) Ash [525 m F s[n] Median (Range)

jC; USGS a] (weight percent on a remnant moisture basis) 23 F 7.3 29 F 13 29 F 12 24 F 12 23 24 27 20 (8.3 – 37) (12 – 50) (7.2 – 61) (6.6 – 54)

Volatile matter (wt.%) m F s[n] 25.2 F 5.0 Median 24.8 (Range) (8.9 – 40.5)

25.9 F 4.3 26.8 (20.5 – 34.2)

27.9 F 4.7 28.0 (9.1 – 35.1)

32.2 F 7.0 34.0 (19.2 – 43.8)

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Table 3 Descriptive statistics for coal analysis: values are stated on an as-received basis except as noted

Fixed carbon (wt.%) m F s[n] 27.6 F 5.7 Median 27.8 (Range) (18.3 – 39.2)

24.3 F 8.2 24.3 (11.0 – 37.5)

24.8 F 3.7 24.6 (21.3 – 28.5)

18.0 F 11.7 12.8 (10.5 – 38.4)

21.0 F 9.3 21.3 (10.5 – 38.4)

26.5 F 7.8 26.6 (8.9 – 44.1)

24 F 7.4[111] 23 (12 – 66)

27 F 3.9[190] 27 (7.8 – 3.6)

Combustible sulfur [total sulfur sulfur in ash] (wt.%) m F s[n] 2.0 F 1.5 2.9 F 1.6 2.1 F 1.7 Median 1.8 2.5 1.9 (Range) (0.06 – 5.3) (0.85 – 5.8) (0.01 – 8.4)

2.8 F 2.8 1.7 (0.03 – 7.2)

2.3 F 1.3 2.1 (0.33 – 4.5)

3.3 F 2.4 3.1 (0.7 – 6.1)

1.3 F 0.92 1.2 (0.39 – 2.8)

2.2 F 1.9 1.3 (0.4 – 6.1)

2.3 F 1.8 1.9 (0.01 – 8.4)

ND ND ND

ND ND ND

Sulfur in ash (wt.%) m F s[n] 0.54 F 0.37 Median 0.52 (Range) (0.03 – 1.99)

0.25 F 0.20 0.22 (0.01 – 0.71)

0.75 F 0.67 0.51 (0.04 – 3.1)

0.70 F 0.61 0.65 (0.03 – 2.1)

1.1 F 0.47 1.1 (0.15 – 1.8)

0.60 F 0.42 0.65 (0.14 – 1.0)

1.1 F 0.45 1.1 (0.40 – 1.6)

0.89 F 0.49 0.98 (0.14 – 1.6)

0.69 F 0.58 0.54 (0.01 – 3.1)

ND ND ND

ND ND ND

Total sulfur (wt.%) m F s[n] 2.6 F 1.5 Median 2.6 (Range) (0.60 – 5.9)

3.1 F 1.5 2.8 (1.1 – 6.0)

2.8 F 1.9 2.4 (0.21 – 9.0)

3.5 F 2.9 2.8 (0.7 – 8.4)

3.4 F 1.4 3.3 (1.0 – 6.2)

3.9 F 2.0 3.8 (1.7 – 6.3)

2.4 F 1.1 1.8 (1.6 – 4.4)

3.1 F 1.6 2.4 (1.6 – 6.3)

2.9 F 1.8 2.7 (0.21 – 9.0)

1.1 F 0.96[111] 0.70 (0.20 – 7.9)

0.98 F 0.61[190] 0.80 (0.20 – 3.2)

Net calorific value (calories per gram) m F s[n] 3030 F 660 3180 F 830 Median 3054 3180 (Range) (1980 – 4650) (1990 – 4650)

3190 F 910 3140 (1270 – 5570)

4000 F 1150 4080 (1940 – 5320)

2890 F 940 3110 (1270 – 4160)

2960 F 620 2960 (2200 – 3720)

2380 F 1700 1480 (1190 – 5300)

2640 F 1310 2530 (1190 – 5300)

3170 F 950 3100 (1190 – 5570)

ND ND ND

ND ND ND

Gross calorific value (calories per gram) m F s[n] 3350 F 620 3480 F 840 Median 3360 3470 (Range) (2340 – 4910) (2240 – 4860)

3480 F 900 3440 (1530 – 5810)

4270 F 1150 4341 (2150 – 5600)

3190 F 920 3430 (1580 – 4460)

3220 F 540 3190 (2580 – 3900)

2680 F 1670 1870 (1410 – 5510)

2920 F 1260 2830 (1410 – 5510)

3470 F 930 3400 (1410 – 5810)

3630 F 910[111] 3600 (1970 – 7600)

3480 F 410[190] 3440 (1560 – 4430)

8140 F 2110 7950 (4710 – 13990)

9680 F 2100 10210 (5690 – 12270)

7080 F 1940 7820 (3070 – 9050)

9070 F 3740 9210 (5070 – 12790)

6820 F 4570 4730 (3760 – 14710)

7820 F 4130 6770 (3760 – 12790)

8050 F 2340 7970 (3070 – 14710)

ND ND ND

ND ND ND

value mmmf b(btu/lb) 7340 F 1600 8530 F 2000 7270 8220 (5120 – 11040) (5850 – 13630)

25.9 F 7.9 25.2 (8.9 – 42.7)

m F s [n] = mass F standard deviation (number of samples if N p n), median and (range); ND = not determined. a USGS = As analyzed by the United States Geological Survey. b Calorific value mmmf (moist mineral matter free basis) is used in ASTM D388 for rank determinations.

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115

32.3 F 7.9 32.2 (17.5 – 44.1)

Calorific m F s[n] Median (Range)

27.2 F 6.5 27.6 (17.4 – 38.9)

95

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5. Results and discussion 5.1. Standard coal analysis For each region, Table 3 gives the mean, standard deviation, median, and range of values for each quantity derived through standard coal analysis. Descriptive statistics are also included for these additional variables: moisture, ash yield (815 jC), volatile matter, fixed carbon, total sulfur, sulfur in the ash, and combustible sulfur and gross calorific values (in calories/gram) on an as-received moisture basis. Due to lack of space, this paper does not provide all the individual data values summarized in Table 3, but it can be obtained as supplemental information in the on-line Appendix A or in geographic information system (GIS) format on the United States Geological Survey Web site http:// geode.usgs.gov. The supplemental information also includes complete sample descriptions, as well as the complete data sets obtained from standard coal analysis

reported on three bases: as-received, residual moisture, and dry. In addition, major and trace elemental concentrations are also reported in three bases: as-received, remnant moisture, and dry. The as-received moisture is the inherent moisture or as-mined moisture and is determined in fresh samples that have been sealed to maintain original moisture. The residual moisture is the moisture of the sample immediately after sample preparation and should be the moisture for samples used in standard coal analysis. The remnant moisture is the moisture determined at the time the coal is ashed for trace element analysis and is generally less than the residual moisture. Parameters reported on a dry basis can be calculated from data on any other basis. In addition, the region-by-region box and whisker plots for proximate analysis (ash, volatile matter, fixed carbon, and moisture), total sulfur, and gross calorific value (on an as-received basis), as well as for the major elements and most of the trace elements, are provided. Finally, the results of the nonparametric statistical

Fig. 2. Relationship of moist mineral matter free calorific value (a rank parameter) to moisture for the 143 Turkish coals studied.

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115

analysis used to evaluate differences among regions are also provided. 5.1.1. Moisture and rank The as-received moisture contents are as high as 57.7%, but many of the samples have less than 20% moisture and some are even below 10%. Minimum values for as-received moisture content are less than 20% for all regions. The average moisture value for the Turkish coals is 26% (Table 3) compared with average moisture values of 35% for 139 U.S. Gulf Coast samples and 38% for 205 Fort Union lignite samples reported in Bragg et al. (1998). This difference is primarily due to a larger percentage of higher rank Turkish coals but may be due in part to the much higher average ash content of the Turkish coals—25 wt.% compared to 12 and 8.6 wt.% for the Gulf Coast and the Fort Union lignite samples, respectively. On an ash-free basis, the Turkish coals have a moisture content of 35% compared to 39% for the Gulf Coast and 41% for the Fort Union lignites. Table 1 shows that most of the Turkish samples are classified as subbituminous or lignitic coal based on petrographic

97

determinations. ASTM D05 0388 procedures (ASTM, 2003) also classify these Turkish coals as low-rank coals (subbituminous coal or lignites) based primarily on calorific values on a moist, mineral matter-free basis (Table 3), but in several cases, the classifications are different from the petrographic classifications in Table 1 (see Fig. 2). The as-received moisture values can be used to estimate rank. Fig. 2 shows the relationship between as-received moisture and rank. All 57 coals with moisture content in excess of 27.6% are classified as lignites by at least one method. All 28 samples with as-received moisture values between 21.5% and 27.6% are classified as either lignites or subbituminous coals by both methods. Of the 32 samples having between 15% and 21.5% as-received moisture, 31 are classified as subbituminous by at least one method and only 1 is classified as a lignite by both methods. All of the 10 samples with as-received moisture contents between 10% and 15% are either subbituminous or bituminous. The remaining 14 coals (as-received moisture less than 10%) are classified as bituminous by one or more technique (see

Fig. 3. Box and whisker plot of as-received moisture. Circles represent outliers, error bars are at the 10th and 90th percentile; the boxes contain values between the 25th and 75th percentile and the line in the box represents the median.

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Table 4 Summary of data analysis results to identify significant differences among regionsa for selected analysesb

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C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115 99

a This chart represents the combination of two non-parametric statistical studies. In the first (variable in all capital letters), all seven geographic regions in Turkey are considered. In the second study (only first letter of variable capitalized), two adjacent regions (Central Anatolia and East Anatolia), represented by four and five samples respectively, are combined (Combined Anatolia). b A complete list of all 43 variables or elements can be found in the supplementary material or in geographic information system (GIS) format on the United States Geological Survey web site http://dss.geode.usgs.gov. c Sig diff reg?=Significant difference between regions? The level of significance is 0.05. d Regions are not significantly different if they share a common bar. In the case of moisture when the Anatolia regions are combined and uranium when the Anatolia is considered individually one bar is not considered continuous only because of high statistical uncertainty for this variable in the Aegean region. In this cases, the break in continuity is represented by a white segment. In all other cases a break in continuity represents different similar regions placed on the same line to conserve space.

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supplemental material). Although care has been taken to maintain original moisture of all samples, some lignites may have lost moisture during or after sampling. This could explain why the few samples with moisture contents similar to those of subbituminous coals are lignites based on calorific values. Five samples have as-received moisture contents in excess of 45%. Some of the differences between petrographic rank and ASTM rank are most likely due to local metamorphism caused by volcanic activity. The higher temperature raises the vitrinite reflectance without other changes caused by higher pressure. Different maceral assemblages may also affect petrographic rank, and small errors in proximate analysis, especially moisture, may affect ASTM rank determinations. The moisture contents of samples from the Black Sea region are generally lower than the moisture contents of samples from any other region except the four samples in the Central Anatolian region. These differences are apparent on the box and whisker plots such as the one shown in Fig. 3. Although the median moisture content of the North Marmara is higher than the median moisture contents of the other regions, its mean moisture content (Table 3) is slightly lower than the mean for the Eastern Anatolia and not significantly different than for the Mediter-

ranean, Combined Anatolia, and Aegean Regions (see Table 4). 5.1.2. Proximate, sulfur, and calorific values The North Marmara region had the lowest average ash yield of any region in Turkey 16.2 F 6.3% and this value is significantly lower than those for any of the Anatolian regions or the Aegean Region (see Table 4). Still, the average ash yield for this region is much higher than those of the two U.S. low-rank coal regions compared (Table 3). The average fixed carbon is highest in samples from the Black Sea Region. Average fixed carbon in samples from this region combined with samples from the North Marmara Region are significantly higher than in samples from the Anatolian and Mediterranean regions, but similar to the average fixed carbon in the two U.S. low-rank coal regions compared in Table 3. This may be due in part to the higher ash content of the samples from the Anatolian region, although the average ash content of the Black Sea Region and the Mediterranean Region are similar. There are no statistical differences among the regions of Turkey with respect to gross calorific value, total sulfur, and volatile matter (see supplemental material). The Turkish coal data for gross calorific value and volatile matter are

Fig. 4. Cross-plot of Gross calorific value in calories/gram on a dry basis with Ash at 815 jC on a dry basis. The R2 value for all points is 0.85. However, if samples are divided by different ranks, the linear regression for each set of points is roughly parallel with gross calorific value and increases with rank and R2 in excess of 0.91 for each line.

Table 5 Descriptive statistics for major elements; all are reported values in weight percent on a remnant (as-determined) moisture basis Regions in Turkey

Summary

USA regions

Region

Marmara North

Marmara South

Aegean

Black Sea

Mediterranean

Central Anatolia

Eastern Anatolia

Combined Anatolia

Total: all of Turkey

Gulf Coast USA

Fort Union USA

Number

N = 28

N = 16

N = 64

N = 13

N = 13

N=4

N=5

N=9

N = 143

N = 142

N = 205

Na m F s[n] Median (Range)

0.15 F 0.13 0.095 (0.013 – 0.47)

0.096 F 0.082 0.097 (0.0055 – 0.31)

0.077 F 0.070 0.049 (0.0096 – 0.36)

0.21 F 0.47 0.047 (0.0064 – 1.7)

0.077 F 0.10 0.040 (0.0072 – 0.39)

0.25 F 0.25 0.20 (0.0060 – 0.60)

0.13 F 0.082 0.12 (0.059 – 0.27)

0.19 F 0.18 0.13 (0.0060 – 0.60)

0.11 F 0.17 0.059 (0.0055 – 1.7)

0.060 F 0.077 0.043 (0.0012 – 0.85)

0.41 F 0.29 0.39 (0.022 – 1.1)

Mg m F s[n] Median (Range)

0.53 F 0.21 0.57 (0.084 – 0.93)

0.30 F 0.29 0.18 (0.054 – 1.2)

0.59 F 0.40 0.52 (0.11 – 1.8)

0.35 F 0.30 0.32 (0.064 – 1.1)

0.52 F 0.32 0.52 (0.16 – 1.3)

0.69 F 0.34 0.58 (0.42 – 1.2)

0.93 F 0.87 0.71 (0.28 – 2.4)

0.82 F 0.66 0.62 (0.28 – 2.4)

0.53 F 0.38 0.48 (0.054 – 2.4)

0.21 F 0.093 0.21 (0.013 – 0.48)

0.36 F 0.099 0.34 (0.15 – 0.63)

Al m F s[n] Median (Range)

1.8 F 0.95 1.9 (0.38 – 3.3)

2.4 F 1.1 2.3 (0.61 – 5.1)

2.3 F 1.4 2.0 (0.33 – 6.6)

1.5 F 1.3 0.86 (0.35 – 4.8)

1.7 F 1.7 1.1 (0.36 – 5.9)

2.9 F 2.3 3.0 (0.84 – 4.9)

2.6 F 1.4 2.5 (1.1 – 4.8)

2.7 F 1.7 2.5 (0.84 – 4.9)

2.1 F 1.4 1.9 (0.33 – 6.6)

1.5 F 0.85 1.2 (0.32 – 3.8)

0.62 F 0.42[201] 0.51 (0.11 – 2.9)

Si m F s[n] Median (Range)

3.9 F 2.3 4.1 (0.38 – 7.9)

6.2 F 4.5 5.0 (0.76 – 17)

5.1 F 3.2 4.4 (0.69 – 13)

5.8 F 4.7 4.7 (0.94 – 14)

4.1 F 4.7 2.0 (0.53 – 17)

6.4 F 5.4 5.9 (1.3 – 13)

8.1 F 4.2 6.6 (5.1 – 16)

7.4 F 4.5 6.6 (1.3 – 16)

5.1 F 3.6 4.3 (0.38 – 17)

3.9 F 2.4 3.3 (0.49 – 10)

1.6 F 1.6[200] 0.97 (0.030 – 10)

K m F s[n] Median (Range)

0.27 F 0.19 0.23 (0.017 – 0.64)

0.33 F 0.36 0.15 (0.035 – 1.1)

0.37 F 0.31 0.28 (0.042 – 1.6)

0.16 F 0.12 0.11 (0.042 – 0.45)

0.30 F 0.46 0.17 (0.031 – 1.7)

0.46 F 0.52 0.29 (0.046 – 1.2)

0.39 F 0.30 0.29 (0.16 – 0.92)

0.42 F 0.38 0.29 (0.046 – 1.2)

0.32 F 0.31 0.23 (0.017 – 1.7)

0.10 F 0.097 0.066 (0.0081 – 0.66)

0.060 F 0.082[201] 0.032 (0.0034 – 0.51)

Ca m F s[n] Median (Range)

0.98 F 0.48 0.90 (0.18 – 2.6)

0.79 F 0.42 0.80 (0.050 – 1.9)

2.3 F 2.8 1.3 (0.19 – 13)

1.5 F 1.3 1.1 (0.17 – 4.5)

2.2 F 1.3 2.2 (0.29 – 4.9)

1.2 F 0.61 1.2 (0.62 – 2.0)

3.2 F 1.4 3.8 (1.1 – 4.4)

2.3 F 1.5 2.0 (0.62 – 4.4)

1.8 F 2.1 1.1 (0.050 – 13)

1.3 F 0.57 1.3 (0.022 – 3.2)

1.2 F 0.31[200] 1.2 (0.68 – 2.9)

Ti m F s[n] Median (Range)

0.079 F 0.043 0.083 (0.0095 – 0.16)

0.093 F 0.047 0.082 (0.13 – 0.021)

0.10 F 0.066 0.091 (0.016 – 0.27)

0.074 F 0.057 0.045 (0.019 – 0.19)

0.093 F 0.12 0.049 (0.014 – 0.46)

0.15 F 0.14 0.11 (0.048 – 0.34)

0.14 F 0.077 0.15 (0.058 – 0.25)

0.15 F 0.10 0.15 (0.048 – 0.34)

0.097 F 0.07 0.082 (0.0095 – 0.46)

0.13 F 0.0927 0.11 (0.024 – 0.74)

0.052 F 0.0624[181] 0.037 (0.0063 – 0.53)

Fe m F s[n] Median (Range)

2.8 F 1.9 2.1 (0.38 – 8.1)

1.7 F 0.97 1.7 (0.52 – 4.2)

2.2 F 1.3 2.0 (0.40 – 5.2)

2.0 F 1.3 1.7 (0.51 – 5.1)

2.4 F 1.6 1.6 (0.56 – 5.2)

3.3 F 2.4 3.2 (0.67 – 5.9)

2.3 F 1.2 1.6 (1.4 – 4.1)

2.7 F 1.8 1.8 (0.67 – 5.9)

2.3 F 1.5 2.0 (0.38 – 8.1)

0.75 F 0.73 0.73 (0.13 – 2.8)

0.75 F 0.57[201] 0.56 (0.074 – 2.8)

Element

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115 101

m F s[n] = mass F standard deviation [number of samples if N p n], median and (range); ND = not determined.

102

Table 6 Descriptive statistics for trace elements; all values in parts per million by weight (ppm) on a remnant (as-determined) moisture basis Regions in Turkey

Summary

USA regions

Region

Marmara North

Marmara South

Aegean

Black Sea

Mediterranean

Central Anatolia

Eastern Anatolia

Combined Anatolia

Total: all of Turkey

Gulf Coast USA

Fort Union USA

Number

N = 28

N = 16

N = 64

N = 13

N = 13

N=4

N=5

N=9

N = 143

N = 142

N = 205

Li m F s[n] Median (Range)

11 F 6.4 11 (1.2 – 24)

25 F 26 18 (4.2 – 110)

19 F 21 14 (1.7 – 140)

6.3 F 6.9 3.2 (1.3 – 26)

11 F 16 5.6 (1.5 – 47)

12 F 8.5 0.083 (5.6 – 24)

15 F 8.3 20 (5.6 – 22)

14 F 8.1 13 (5.6 – 24)

16 F 18 11 (1.2 – 140)

10 F 7.3 9.2 (0.86 – 44)

3.5 F 3.0 3.0 (0.34 – 33)

Be m F s[n] Median (Range)

1.1 F 0.47 1.1 (0.44 – 2.3)

1.6 F 0.91 1.5 (0.28 – 3.9)

1.6 F 1.2[58] 1.4 (0.21 – 6.3)

0.89 F 0.76[11] 0.60 (0.32 – 2.9)

0.63 F 0.58[11] 0.40 (0.15 – 2.1)

1.5 F 1.3[3] 0.78 (0.73 – 3.0)

0.92 F 0.38[3] 0.72 (0.68 – 1.4)

1.2 F 0.92[6] 0.75 (0.68 – 3.0)

1.3 F 0.97[130] 1.1 (0.15 – 6.3)

2.0 F 1.5[138] 1.5 (0.22 – 11)

0.92 F 1.6[143] 0.47 (0.084 – 16)

B m F s[n] Median (Range)

160 F 89 130 (38 – 370)

310 F 260 190 (31 – 720)

260 F 240 160 (56 – 1200)

250 F 190 180 (60 – 780)

99 F 70 77 (22 – 290)

160 F 170 87 (46 – 400)

110 F 65 130 (40 – 200)

130 F 110 120 (40 – 400)

220 F 200 150 (22 – 1200)

120 F 78 95 (6.4 – 440)

130 F 77 110 (20 – 600)

P m F s[n] Median (range)

120 F 82 88 (13 – 360)

200 F 140 160 (42 – 450)

210 F 180 180 (23 – 1000)

180 F 160 0.012 (26 – 490)

300 F 320 210 (25 – 1200)

200 F 160 180 (28 – 400)

430 F 280 500 (100 – 790)

330 F 250 250 (28 – 790)

200 F 190 140 (13 – 1200)

310 F 300 200 (17 – 1300)

290 F 216[201] 290 (8.8 – 980)

Sc m F s[n] Median (Range)

4.6 F 2.3 5.2 (0.87 – 8.8)

5.2 F 3.2 4.6 (1.2 – 14)

5.5 F 3.9[63] 4.2 (1.1 – 23)

2.9 F 2.6[12] 2.0 (0.43 – 9.2)

3.5 F 3.2 2.5 (0.88 – 12)

4.2 F 2.7 4.3 (1.5 – 6.7)

4.8 F 3.7 3.0 (2.2 – 11)

4.5 F 3.1 3.0 (1.5 – 11)

4.8 F 3.4[141] 4.1 (0.43 – 23)

4.5 F 2.2 4.0 (1.0 – 12)

2.0 F 1.8[196] 1.4 (0.39 – 14)

V m F s[n] Median (Range)

41 F 19 46 (10 – 76)

81 F 49 71 (14 – 190)

68 F 46 57 (14 – 270)

62 F 46 42 (5.5 – 150)

66 F 54 42 (7.9 – 200)

73 F 17 73 (56 – 91)

100 F 73 87 (33 – 180)

90 F 55 86 (33 – 180)

65 F 45 52 (5.5 – 270)

11 F 18 28 (4.9 – 110)

11 F 14 7.4 (1.1 – 110)

Cr m F s[n] Median (Range)

43 F 22 41 (9.7 – 77)

48 F 71 16 (8.5 – 270)

110 F 100 73 (12 – 540)

41 F 43 20 (3.7 – 130)

65 F 58 42 (7.4 – 200)

34 F 18 38 (13 – 49)

93 F 100 39 (26 – 270)

67 F 80 39 (13 – 270)

75 F 83 45 (3.7 – 540)

6.8 F 8.3 12 (0.0070 – 64)

6.8 F 10 3.3 (0.83 – 64)

Mn m F s[n] Median (Range)

67 F 31 66 (13 – 150)

180 F 150 180 (27 – 650)

120 F 88 91 (16 – 430)

100 F 80 72 (19 – 290)

79 F 77 54 (14 – 310)

120 F 62 130 (53 – 180)

130 F 71 120 (42 – 210)

130 F 63 120 (42 – 210)

110 F 92 81 (13 – 650)

84 F 134 120 (7.4 – 670)

84 F 74 68 (7.3 – 670)

Co m F s[n] Median (Range)

6.6 F 3.5 6.7 (1.3 – 17)

13 F 12 8.2 (2.0 – 40)

13 F 11 9.3 (2.0 – 51)

7.4 F 5.4 7.1 (1.0 – 16)

7.4 F 7.2 4.5 (0.87 – 25)

6.8 F 4.4 7.4 (1.4 – 11)

7.4 F 5.8 5.3 (4.0 – 18)

7.1 F 4.9 5.3 (1.4 – 18)

10 F 9.3 7.0 (0.87 – 51)

4.5 F 4.4 3.5 (1.0 – 30)

2.7 F 6.6[202] 1.1 (0.080 – 68)

Element

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115

53 F 26 54 (3.5 – 99)

130 F 280 18 (8.2 – 960)

220 F 310 81 (8.8 – 1600)

130 F 130 100 (3.1 – 450)

140 F 190 72 (5.6 – 750)

58 F 38 62 (7.1 – 100)

87 F 75 56 (30 – 220)

74 F 60 59 (7.1 – 220)

150 F 250 64 (3.1 – 1600)

10 F 9.9 8.3 (1.8 – 77)

4.0 F 7.6 2.1 (0.55 – 84)

Cu m F s[n] Median (Range)

16 F 8.9 18 (3.5 – 43)

14 F 6.2 13 (4.9 – 26)

24 F 21 15 (3.9 – 100)

17 F 13 11 (1.5 – 42)

13 F 10 9.7 (2.8 – 35)

21 F 12 22 (7.5 – 33)

24 F 29 11 (8.0 – 76)

23 F 22 14 (7.5 – 76)

20 F 17 14 (1.5 – 100)

20 F 11 18 (3.3 – 69)

6.9 F 6.8 5.1 (1.3 – 78)

Zn m F s[n] Median (Range)

37 F 33 28 (7.0 – 140)

48 F 60 32 (10 – 260)

41 F 27 34 (8.1 – 130)

34 F 32 19 (6.8 – 120)

35 F 31 23 (5.8 – 120)

45 F 22 37 (29 – 77)

58 F 35 43 (33 – 120)

52 F 29 42 (29 – 120)

40 F 34 32 (5.8 – 260)

19 F 23 13 (1.7 – 200)

11 F 18 5.1 (0.54 – 170)

Ga m F s[n] Median (Range)

4.7 F 2.2 5.2 (0.85 – 8.8)

6.5 F 3.3 6.3 (1.3 – 15)

7.0 F 4.5 5.9 (1.6 – 20)

3.1 F 2.2 2.1 (0.88 – 7.6)

4.5 F 5.3 3.0 (0.99 – 20)

5.5 F 4.3 4.2 (2.1 – 11)

5.8 F 3.1 5.4 (2.2 – 9.8)

5.7 F 3.4 5.4 (2.1 – 11)

5.8 F 4.0 5.4 (0.85 – 20)

6.7 F 3.7[140] 6.1 (1.2 – 22)

3.1 F 2.7[193] 2.3 (0.38 – 16)

Ge m F s[n] Median (Range)

2.1 F 2.9 1.2 (0.47 – 16)

7.1 F 9.0 3.6 (0.28 – 35)

3.9 F 5.6[60] 1.7 (0.22 – 30)

4.3 F 10 1.7 (0.43 – 38)

3.8 F 6.3[11] 0.85 (0.088 – 21)

1.2 F 0.92 0.93 (0.52 – 2.6)

2.6 F 2.3 1.4 (0.67 – 6.2)

2.0 F 1.9 1.3 (0.52 – 6.2)

3.8 F 6.2[137] 1.6 (0.088 – 38)

4.4 F 4.3[120] 3.1 (0.25 – 36)

2.5 F 2.9[64] 1.4 (0.13 – 13)

As m F s[n] Median (Range)

30 F 43 15 (3.2 – 210)

70 F 95 26 (7.8 – 340)

79 F 120 34 (4.2 – 620)

59 F 70 26 (3.3 – 220)

44 F 65 13 (1.8 – 180)

140 F 240 27 (20 – 500)

72 F 62 47 (14 – 170)

100 F 160 36 (14 – 500)

65 F 100 26 (1.8 – 620)

4.3 F 3.5 3.1 (0.96 – 22)

8.4 F 7.6[185] 6.3 (1.0 – 63)

Se m F s[n] Median (Range)

0.81 F 0.49[26] 0.77 (0.045 – 2.2)

0.63 F 0.41[10] 0.46 (0.20 – 1.5)

2.8 F 4.5[56] 1.5 (0.10 – 24)

2.6 F 2.2 1.6 (0.25 – 6.3)

2.6 F 1.6 2.1 (0.80 – 6.3)

3.2 F 1.3 3.1 (1.7 – 4.7)

4.0 F 7.3 0.90 (0.51 – 17)

3.6 F 5.2 1.7 (0.51 – 17)

2.2 F 3.5[127] 1.2 (0.045 – 24)

5.5 F 2.7[140] 5.0 (0.070 – 14)

0.79 F 0.49[202] 0.66 (0.070 – 3.4)

23 F 16 23 (0.94 – 47)

21 F 24 10 (2.5 – 76)

31 F 32 25 (4.5 – 210)

9.2 F 7.0 6.2 (2.9 – 24)

19 F 26 12 (1.8 – 90)

16 F 10 14 (5.2 – 29)

23 F 16 19 (7.4 – 49)

20 F 13 18 (5.2 – 49)

25 F 26 19 (0.94 – 210)

19 F 14[45] 14 (6.0 – 63)

ND ND (ND)

Sr m F s[n] Median (Range)

210 F 100[27] 210 (45 – 430)

180 F 140 130 (77 – 590)

180 F 170[63] 140 (2.7 – 830)

210 F 120 180 (73 – 480)

240 F 120 230 (71 – 430)

590 F 490 440 (200 – 1300)

340 F 160 330 (180 – 560)

450 F 340 330 (180 – 1300)

210 F 170[141] 170 (2.7 – 1300)

240 F 201 170 (5.7 – 1100)

330 F 182 290 (42 – 1300)

Y m F s[n] Median (Range)

8.1 F 6.6 6.5 (4.0 – 40)

7.8 F 3.6 6.9 (2.0 – 16)

10 F 8.6 7.8 (2.0 – 43)

4.7 F 4.7 3.1 (0.98 – 18)

4.9 F 4.7 3.8 (1.2 – 17)

6.3 F 4.3 4.8 (2.9 – 12)

6.1 F 3.1 4.4 (3.1 – 10)

6.2 F 3.5 4.4 (2.9 – 12)

8.3 F 7.1 6.5 (0.98 – 43)

14 F 12 11 (0.27 – 100)

6.4 F 7.5[200] 4.7 (0.97 – 84)

Rb m F s[n] Median (Range) Y

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115

Ni m F s[n] Median (Range)

(continued in next page)

103

104

Table 6 (continued) Regions in Turkey

Summary

USA regions

Region

Marmara North

Marmara South

Aegean

Black Sea

Mediterranean

Central Anatolia

Eastern Anatolia

Combined Anatolia

Total: all of Turkey

Gulf Coast USA

Fort Union USA

Number

N = 28

N = 16

N = 64

N = 13

N = 13

N=4

N=5

N=9

N = 143

N = 142

N = 205

Nb m F s[n] Median (Range)

2.4 F 1.4[26] 2.1 (0.82 – 6.2)

5.9 F 3.6 5.6 (0.55 – 17)

4.8 F 3.3[58] 4.0 (1.1 – 20)

2.0 F 1.9 1.2 (0.48 – 6.8)

3.1 F 4.7 1.6 (0.26 – 14)

3.7 F 3.1 2.8 (1.2 – 8.2)

3.7 F 2.4 2.9 (1.1 – 7.2)

3.7 F 2.6 2.9 (1.1 – 8.2)

4.0 F 3.2[135] 3.1 (0.26 – 20)

5.8 F 5.3[132] 3.7 (0.52 – 31)

2.4 F 1.8[115] 1.8 (0.33 – 11)

Mo m F s[n] Median (Range)

2.7 F 1.7 2.3 (0.43 – 6.4)

6.3 F 3.7 5.9 (1.5 – 14)

12 F 13 7.8 (0.83 – 69)

7.7 F 7.1 5.1 (1.0 – 20)

17 F 14 18 (0.80 – 50)

13 F 11 12 (2.4 – 25)

19 F 21 10 (3.6 – 55)

16 F 16 10 (2.4 – 55)

9.8 F 12 5.4 (0.43 – 69)

2.0 F 1.5[123] 1.6 (0.13 – 8.5)

3.8 F 19[201] 1.7 (0.27 – 280)

Sb m F s[n] Median (Range)

0.73 F 0.31[22] 0.64 (0.23 – 1.2)

1.3 F 1.0[14] 0.97 (0.48 – 3.7)

4.6 F 7.4[60] 2.4 (0.43 – 41)

0.89 F 0.99 0.46 (0.12 – 3.3)

1.1 F 0.87[11] 0.82 (0.20 – 2.6)

1.8 F 1.6 1.4 (0.49 – 3.9)

1.7 F 1.0 1.7 (0.60 – 2.7)

1.7 F 1.2 1.7 (0.49 – 3.9)

2.7 F 5.4[129] 1.1 (0.12 – 41)

0.87 F 0.51 0.74 (0.070 – 2.8)

0.58 F 0.74[204] 0.39 (0.070 – 7.3)

Cs m F s[n] Median (Range)

2.2 F 1.4 2.5 (0.054 – 4.8)

9.1 F 12 3.7 (0.94 – 38)

6.5 F 9.2 3.5 (0.50 – 50)

0.93 F 0.80 0.62 (0.14 – 2.5)

2.9 F 4.0 1.4 (0.13 – 15)

1.7 F 0.75 1.4 (1.0 – 2.8)

3.3 F 4.2 1.9 (0.47 – 11)

2.6 F 3.1 1.4 (0.47 – 11)

4.9 F 7.9 2.5 (0.054 – 50)

0.48 F 0.46[50] 0.35 (0.053 – 2.0)

ND ND ND

Ba m F s[n] Median (Range)

92 F 57 83 (15 – 230)

170 F 130 140 (23 – 590)

150 F 93 130 (27 – 390)

94 F 68 75 (19 – 270)

110 F 87 94 (27 – 330)

77 F 41 70 (37 – 130)

210 F 180 180 (60 – 510)

150 F 150 93 (37 – 510)

130 F 96 110 (15 – 590)

180 F 175 135 (17 – 1300)

680 F 10 490 (13 – 13000)

Hg m F s[n] Median (Range)

0.077 F 0.039[27] 0.11 F 0.15 0.070 0.070 (0.030 – 0.16) (0.030 – 0.66)

0.14 F 0.096[62] 0.12 (0.030 – 0.65)

0.085 F 0.028 0.080 (0.050 – 0.13)

0.075 F 0.033[11] 0.16 F 0.13 0.070 0.11 (0.040 – 0.15) (0.060 – 0.35)

0.12 F 0.12[4.0] 0.065 (0.050 – 0.29)

0.14 F 0.12[8.0] 0.070 (0.050 – 0.35)

0.11 F 0.093[137] 0.22 F 0.17 0.090 0.16 (0.030 – 0.66) (0.010 – 1.0)

0.13 F 0.13 0.11 (0.0070 – 1.2)

Pb m F s[n] Median (Range)

6.1 F 3.6[27] 6.3 (1.1 – 16)

12 F 7.7 10 (2.3 – 35)

11 F 9.4[62] 9.0 (1.2 – 58)

4.1 F 3.7 2.3 (0.95 – 14)

8.0 F 7.8[11] 4.5 (1.6 – 21)

13 F 14 6.0 (5.2 – 33)

5.5 F 1.9 4.8 (3.6 – 8.5)

8.7 F 9.2 6.0 (3.6 – 33)

9.3 F 8.2[138] 6.8 (0.95 – 58)

8.3 F 5.7 6.3 (0.87 – 29)

3.7 F 2.2 3.1 (0.35 – 13)

U m F s[n] Median (Range)

2.1 F 1.3 1.8 (0.32 – 5.5)

7.3 F 4.4 6.6 (1.7 – 18)

20 F 24 15 (1.0 – 140)

2.4 F 2.4 1.4 (0.44 – 8.8)

13 F 6.6 14 (1.7 – 22)

18 F 14 18 (2.3 – 34)

12 F 10 15 (0.74 – 26)

15 F 12 15 (0.74 – 34)

13 F 18 6.9 (0.32 – 140)

2.3 F 1.7 1.9 (0.18 – 17)

1.5 F 1.9 0.96 (0.049 – 13)

Element

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115

m F s[n] = mass F standard deviation [number of samples if N p n], median and (range); ND = not determined.

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115

similar to those from the two U.S. coal regions, but the average for total sulfur in Turkish coal is over two times higher than in U.S. low-rank coal. Cross-plots have been shown to be a powerful tool for evaluating coal data (Hoeft et al., 1983; Luppens, 1982). The most useful of these plots for this study is the plot of the gross calorific value on a dry basis against the ash (815 jC on a dry basis: Fig. 4). The overall coefficient of determination (R2) is 0.85. However, the points are clearly rank-dependent and separate plots of the trendlines for lignite, subbituminous, and bituminous sample sets have R2 values greater than 0.91.

105

al. (1998) which was also reported on a remnant moisture basis. The average remnant moisture for the Turkish coals is 7.4% (Table 3) with a maximum of 11.7%. In general, the values reported in this paper are less than 10% lower than those same values reported on a dry basis. In addition, numerical average elemental concentrations of samples taken from the 26 largest mines, representing about 80% of all the coal mined in Turkey in 2001, and weighted averages of those samples based on tons of coal mined are given in Table 7. The weighted average of the 26 largest mines were less than 20% different than the overall averages for about half of the elements shown in Table 7. Elements having differences larger than 20% are discussed below. As with results from the standard coal analysis given in Table 3, this paper does not provide all the individual elemental values or production figures, but they can be obtained as supplemental material (as well as values on a dry basis) in the on-line Appendix A or in geographic information system (GIS) format on the United States Geological Sur-

5.2. Major elements and trace elements For each region, the average major element concentrations (Table 5) and the average trace element concentrations (Table 6) were determined on a remnant moisture basis. This basis was chosen for this paper so that direct comparison could be made with previous U.S. data reported by Bragg et

Table 7 Average values of selected elements for all samples compared to the numerical average values for those elements in the 26 largest mines representing 80% of the production in Turkey and a weighted average for those 26 mines based on production USGS ash (%) All Turkey average (143 mines) Numerical average for largest 26 mines Weighted average for largest 26 mines

28.0 27.6 30.0 S (%)

All Turkey average (143 mines) Numerical average for largest 26 mines Weighted average for largest 26 mines

All Turkey average (143 mines) Numerical average for largest 26 mines Weighted average for largest 26 mines

All Turkey average (143 mines) Numerical average for largest 26 mines Weighted average for largest 26 mines

3.7 2.6 2.2

RM moist (%)

Na (%)

Al (%)

7.4 7.7 8.7

0.11 0.11 0.08

5.1 5.0 5.0

2.1 2.1 2.4

Li (ppm)

Be (ppm)

B (ppm)

P (ppm)

220 225 210

200 350 390

Ga (ppm)

Ge (ppm)

5.8 5.4 6.9

3.8 2.1 2.0

Cs (ppm)

Ba (ppm)

16 18 21

1.3 1.0 1.1

Ni (ppm)

Cu (ppm)

Zn (ppm)

150 131 169

20 17 21

40 46 47

Nb (ppm)

Mo (ppm)

Sb (ppm)

4.0 4.2 5.3

Si (%)

9.8 12 12

2.7 1.8 2.0

4.9 4.2 4.4

130 188 174

Ca (%) 1.8 2.5 2.9 Sc (ppm) 4.8 4.2 5.3 As (ppm) 65 46 30

Mg (%) 0.53 0.49 0.54

K (%) 0.32 0.23 0.27

Fe (%) 2.3 1.7 1.6

Ti (%) 0.097 0.106 0.123

V (ppm)

Cr (ppm)

Mn (ppm)

Co (ppm)

65 86 119

75 91 151

110 105 114

10 7.6 9.2

Se (ppm)

Rb (ppm)

Sr (ppm)

Y (ppm)

2.2 2.9 6.2

Hg (ppm)

Pb (ppm)

0.11 0.15 0.11

9.3 7.4 7.5

25 17 21 U (ppm) 13 13 16

RM moist = remnant moisture. The ash value and all elemental concentrations are reported on a remnant moisture basis.

210 242 212

8.3 7.8 9.9

106

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vey Web site http://geode.usgs.gov. The supplemental data for major elements provide the same level of detail as the file containing the results from standard coal analysis. 5.2.1. Major elements Statistical analysis indicates that all of the major elements except Ca and Na correlate with ash with a significance level of at most 0.0001 (99.99% confidence interval). Average concentrations of the major elements in Turkish coals are not substantially different from those reported by Bragg et al. (1998) for the U.S. coal samples from the Gulf Coast and Fort Union regions. However, as in the case of ash (Table 3), the mean, median, and maximum values for all the major elements in the Turkish coals are higher than the corresponding values for the U.S. coals, except for the mean and median Na values reported for the Fort Union region. The highest average and median concentrations for all the major elements are generally in either the Eastern Anatolian or the Central Anatolian or Combined Anatolian regions (see Table 5). This is not surprising since these two regions have the highest average and median ash contents. There is no significant difference among regions with respect to Fe, Si, and Ti. The same can be said of Na; however, if the Combined Anatolian region is considered, it (and the North Marmara Region) has a significantly higher mean of the rank values for these elements than do the Aegean, Black Sea, and Mediterranean regions (see Table 4). The Anatolian regions have significantly higher means of rank values of Al and K concentrations than do Black Sea or the Mediterranean regions and significantly higher means of rank values of Mg concentrations than do Black Sea and South Marmara regions. Major element concentrations in coal provide indications of the proportions of minerals found in coal. Typically, oxides of major ash producing elements in coal are summed to help determine the accuracy of the analysis. Generally, this works well for high-rank coals, but typically, oxides do not add up to 100% for low-rank coals. The average sum of the oxides was 92% for the Turkish coals. One reason for the low sum is that calcite and some other carbonates are not converted to oxides in the 525 jC ashing processes used in this study. This would result in low summa-

tions because the carbonate in the ash is not determined. Several of the coals in this study had very high Ca: up to 13% on a whole coal basis (Table 5) or up to 45% CaO on an ash basis (see supplemental material). Similarly, Mg may also remain as carbonates. If Ca and Mg are assumed to form sulfates and/or carbonates, then the average of the oxides is 97 –104% (see supplemental material). This number could be high if some of the Ca and Mg occurs as oxides in the ash. Low oxide totals may be explained by the presence of unburned carbon caused by incomplete combustion, especially at 525 jC, the temperature used by the USGS to keep certain trace elements from volatilizing. To test these two hypotheses, carbonate carbon and organic carbon were determined for selected samples using a carbon, hydrogen, and nitrogen (CHN) procedure described by Orem et al. (1999). Carbon was also analyzed in the samples with an electron microprobe analyzer using a broad beam, semiquantitative approach, and we also confirmed the presence of CaCO3 [and ankerite, Ca(Fe,Mg,Mn) (CO3)2 in at least one coal] by X-ray diffraction analysis (XRD). The results for samples in Table 8 show that calcite determined by CHN can be as high as 57% of the ash. This would make a difference of 27% for this sample, increasing the sum from 78% to 105%. ICP-AES results suggest that the amount of calcite may be even higher. In all cases, the amount of organic C was less than 0.5% for the samples in Table 8 and will make little difference in the mass balance. Major element analysis can be used to determine adverse coal utilization potential such as slagging, abrasion, and fouling. Empirical formulae have been developed to help predict problems with using certain coals in certain types of boilers (Vaninetti and Busch, 1982). Care should be used in applying these formulae for all coals or boilers, but the formulae can be used as a guide to anticipate possible problems. Table 9 summarizes the results for calculating the fouling, slagging, and abrasion potential of Turkish coals. A complete table of results as well as definitions of the factors is included in the supplemental material. Slagging refers to ash that melts and fuses to boiler walls. The six factors used to determine slagging potential are base/acid ratio, silica ratio, slagging factor, dolomite ratio, iron –calcium ratio, and sili-

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Table 8 Determination of calcite by carbon, hydrogen, nitrogen analyzer (CHN), electron microprobe analysis (MPA), calcium and sulfate analysis (CHEM), and X-ray diffraction analysis (XRD) Sample Total C Carbonate C Total CHN Total C Total MPA Maximum Total Chem XRDa number (CHN) C (CHN) CaCO3b (MPA) CaCO3c CaCO3d CaCO3e

Carbonates present XRD

2933 2376 2421 2448 2465 4875 10814 27158 27092 27068

no calcite calcite lots of calcite and some ankerite calcite calcite no calcite trace calcite calcite trace calcite calcite

0.12 2.53 7.11 1.60 3.25 0.11 0.64 4.12 1.27 1.96

ND 2.20 6.86 1.17 2.84 ND 0.36 3.90 1.10 1.63

0.0 18.3 57.2 9.8 23.7 0.0 3.0 32.5 9.2 13.6

1.3 2.7 4.7 2.5 2.1 0.0 0.3 2.1 0.5 1.7

10 20 40 20 20 0 3 20 4 10

17 50 74 59 68 15 9 56 42 51

0 22 68 26 26 0 3 34 7 22

DAMHTQ? DAMCmHTQF DCMAQTAnH?Sp? DAMCQTPHB DAMCTQHBS MAIQTKH? MQHImATC DAMCHmQ DAMHTQC DAMCHTQFeld

a

Symbols under XRD: D = Dominante: mineral following is greater than 50% of ash ;M = Major: minerals following are less than 50% of ash but greater than 10%; m = minor: minerals following are between 5% and 10% and T = trace minerals following are less than 5%. A ‘?’ after the mineral means that the detection of the mineral is uncertain. A = anhydrite, An = ankerite, B = bassinite, C = calcite, Do = dolomite, F = feldspar, H = hematite, I = illite, K feldspar, P = plagioclase, Q = quartz, S = sphalerite. b Assumes all carbonate carbon (C) from CHN analysis is CaCO3. c Assumes all carbon determined by microprobe analysis is CaCO3 (these results are semiquantitative). d Assumes all Ca in the original sample formed exists as CaCO3 in the ash. This is unlikely but should provide a maximum value. e Assumes SO3 in the ash exists as CaSO4 and only excess Ca will form CaCO3 [excess SO3 will form MgSO4 and Fe2(SO4)3].

ca –alumina ratio. Each of these factors needs to be evaluated independently because any one of them can contribute to slagging problems. Some of these factors are useful for determining slagging potential in bituminous coals while others are more useful for lowrank coals. Only 17 samples did not exhibit slagging tendencies for any of the parameters. None of the samples exhibited slagging potential for all parameters. The slagging risk reported by the iron/calcium ratio had the highest number of moderate- to high-risk low-rank samples (79 of 121 samples), with up to 6 more of 11 additional samples where the rank was either subbituminous or bituminous as determined by ASTM (2003). Fouling is the accumulation of sintered ash on boiler tubes in the convective passes of coal boilers (Vaninetti and Busch, 1982). Only a few Turkish lowrank coals have fouling potential as measured by Na2O in coal ash or Cl in coal. A much larger percentage of high-rank samples (up to 12 of the 22 samples) shows fouling tendencies using the alkali in coal parameter. Abrasion is a potential problem in Turkish coals. Seventy-eight of the 143 samples had high abrasion potential as measured by the silica/alumina ratio. In addition, 4 samples showed severe abrasion potential

with a silica/alumina ratio of over 10. This high silica/alumina ratio is also likely to increase the slagging potential for these samples. In general, abrasion in boilers is a common characteristic of high-ash coals. The weighted Ca and P averages for samples based on production values representing the 26 largest mines were more than 50% higher than the average for all 143 samples (Table 7). For both Ca and P, the numerical average for these 26 mines was closer to the weighted average than the average for all 143 samples, suggesting that the weighted average is not significantly altered by a single sample from a very large mine. In contrast, the numerical Ti average for the 26 largest mines is only 11% higher than the average for all of the 143 samples in the study, but the weighted average for the largest 26 mines is nearly 27% higher than the average for all 143 samples. This is because 5 samples have relatively high Ti concentrations. The weighted average for Na and Fe was more than 30% lower than the average for all of the 143 samples. For Fe, the numerical average of the 26 largest mines was nearly the same as the weighted average of the 26 largest mines, but for Na, the average for all 143 samples and the numerical average for the 26 largest

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Index

Factorsa

Applications

Low

Number of samplesb

Medium – high

Number of samplesb

Severec

Number of samples

Total number of samplesb

Slagging potential Base/acid ratio Base/acid ratio Base/acid ratio Iron/Calcium Silica ratio Slagging factor

Base/Acid Base/Acid Base/Acid Fe2O3/CaO SiO2/SiFeCaMg (Base/Acid)(S dry)

low rank high rank high rank low rank high rank high rank

< 0.25 or >0.8 < 0.5 >0.27 < 0.31or >3.0 < 0.3 < 0.6

55(5) 9(9) 9(9) 42(4) 1(0) 10(11)

0.25 – 0.80 >0.5 < 0.27 0.31 – 3.0 0.3 – 0.82 0.6 – 2.6

66(6) 2(2) 2(2) 79(7) 7(9) 1(0)

See M-H See M-H See M-H See M-H >0.82 >2.6

NA NA NA NA 3(2) 0(0)

121(11) 11(11) 11(11) 121(11) 11(11) 11(11)

Abrasion potential Silica – alumina ratio

SiO2/Al2O3

all rankse

< 2.4

61

2.4 – 10

78

>10

4

143

Fouling potential Fouling factor Alkali in coal Sodium in ash Sodium in ash Chlorine in coal

(Base/Acid)  Na2O Ash(NaK)/100 Na2O Na2O Cl

high rank high rank high rank low rank all ranks

< 0.2 < 0.3 < 0.5 < 3.0 < 0.2

7(7) 2(8) 6(11) 119(10) 143

0.2 – 1.0 0.3 – 0.6 0.5 – 2.5 3.0 – 5.0 0.2 – 0.5

3(4) 6(1) 5(0) 2(1) 0

>1.0 >0.6 >2.5 >5.0 >0.5

1(0) 3(2) 0(0) 0(0) 0

11(11) 11(11) 11(11) 121(11) 143

Commentsd

DB WB DB

a All values in weight percent in the ash except for S dry and Cl which are weight percent on the whole coal on a dry basis. Abbreviations include: Base = Fe2O3 + CaO + MgO + K2O + Na2O; Acid = SiO2 + TiO2 + Al2O3; SiFeCaMg = SiO2 + Fe2O3 + CaO + MgO; NaK = Na2O + 0.659  K2O. b Number in parentheses represent number of samples that may be either high-rank (bituminous) or low-rank subbituminous using ASTM procedures. c See M – H = see medium to high; no additional information on severe. d Values are applicable to all boiler types except where noted: DB (dry bottom boilers) or WB (wet bottom boilers); actual boiler type for burning individual samples is not known. e High Silica-alumina ratios are also known to have slagging potential for low rank coals. Actual values are not reported in the literature but it should be expected that the ratios over 10 would have severe slagging potential as well as severe abrasion potential.

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Table 9 Summary of slagging, fouling, and abrasion parameters for Turkish coals

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mines were the same. This is because the highest Na value (more than 50 times the average) in the 26 mines is represented by less than 0.3% of the coal production. The weighted averages for Si, Al, Mg, and K were similar to both the average for all of the 143 samples and the numerical average for the 26 largest mines. 5.2.2. Trace elements 5.2.2.1. Comparison of Turkish coals to U.S. lignite regions. Statistical analysis of the Turkish trace element data are reported in Table 6. All elemental concentrations are reported on an as-determined remnant moisture-whole-coal basis; see Table 3 for moisture values. Elements with greater than 1/8 of the data reported as ‘‘less than’’ values are not included in Table 6, but the individual data for these elements are included in the supplemental material. Most elemental concentrations are higher than those found in the Gulf Coast and Fort Union regions, but these differences can usually be accounted for by higher average ash content in Turkish coals (two to three times higher) than for the U.S. lignites. A few elements had average or maximum values greater than three times the corresponding values in U.S. lignites. In subsequent paragraphs, elements with the largest differences from U.S. lignites will be discussed before elements that are similar to U.S. lignites. Some of the elements with large differences are known to be potentially toxic. A determination of actual health risk to the Turkish population is beyond the scope of this paper and would likely require additional information about the toxicity of the elements, their modes of occurrence, leaching characteristic from coal and fly ash, and volatilization characteristics. Therefore, the general information presented on toxicity of elements and a few examples where coal use in areas outside Turkey has lead to adverse health affects is given in the following discussion as background information and does not indicate a known threat to the Turkish population. Finkelman et al. (2002) provide additional information on health impacts from coal use. The concentration of Ni in the Turkish coal samples is very high (up to 1553 ppm on a coal basis and up to 4150 ppm on an ash basis). The concentration of Ni in Turkish coals does not corre-

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late with ash but does correlate with Cr. Nearly 40% of the samples in this study, including samples from all Turkish geographic regions, had values higher than the maximum reported for U.S. lignites (84 ppm in the Fort Union region). Although Ni is not regulated in the United States, breathing or ingesting small particles to nickel oxides can cause adverse health effects (ATSDR, 2003). Some Turkish coals have more than 200 times the mean Ni value for the U.S. lignite regions (6.4 ppm). The form of the Ni, as well as its concentration, is important in determining its toxicity. The form is likely to be different in fly ash produced during energy production than the feed coal, and Ni leached from the coal or fly ash. The Turkish coal samples generally have higher Cr contents than U.S. coals. The maximum value of Cr detected is 542 ppm. The average concentration of Cr in Turkish coal is 75 ppm, which is more than 10 times the average concentration in U.S. lignite regions (6.8 ppm) and is greater than the maximum concentration reported by Bragg et al. (1998) for U.S. lignites (64 ppm). Moreover, 36% of the Cr values, including samples from all regions except the Central Anatolia, are greater than the maximum U.S. lignite values. The weighted average of Cr in the 26 largest mines (151 ppm; Table 7) is more than twice the average concentration for all 143 samples in this study. This is due to high Cr content (>200 ppm) in four samples from mines producing more than 30% of the coal mined in Turkey in 2001. Exposure to high concentrations of chromium, especially Cr6 +, can have serious adverse health effects (ATSDR, 2003). Hexavalent chromium is not common in coal but can be found in the fly ash produced by oxidation during coal burning (Hwang and Wang, 1994). Following combustion, volatilized Cr can oxidize and precipitate on the surfaces of fly ash particles (Sheps et al., 1999) resulting in greater exposure to hexavalent Cr and a much greater health risk. The Turkish coal samples generally have higher As contents than U.S. coals. The maximum value of As observed is 620 ppm. The average concentration of As in Turkish coal is 65 ppm, about 10 times greater than the average value of 6.6 ppm for As in the U.S. lignites. The average As concentration in the Turkish coals is greater than the maximum concentration

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reported by Bragg et al. (1998) for U.S. lignites (63 ppm As for the Fort Union). Nearly 90% of the As values in Turkish coals are greater than the average arsenic concentration in U.S. lignites. The weighted average of As based on production from the 26 largest mines (30 ppm; Table 7) was less than half of the average of all 143 samples but is about five times higher than the average As in U.S. lignites. Karayigit et al. (2000b) report As concentrations as high as 3854 ppm (averaging 833 ppm) in borehole samples from the Golker coalfield in the Aegean Region. A sample in the present study taken from a mine near the Golker coalfield contains 475 ppm As. Arsenic mobilized from residential coal use has caused thousands of cases of severe arsenic poisoning in Guizhou Province, China (Finkelman, 2002). However, the concentration of As in the Chinese coals is exceptionally high, up to 35,000 ppm, and the Chinese were burning it in unvented stoves, maximizing their exposure. Bencko and Symon (1977) found measurable hearing loss in children who were exposed to arsenic from a power plant in the former Czechoslovakia that was burning lignite with 900– 1500 ppm arsenic (dry basis; approximately 800 – 1350 on a remnant moisture basis). The health effects of As emissions from a coalburning power plant would be influenced by the concentration of As, its mode of occurrence in the coal, the types and efficiency of the pollution control systems, and the routes of exposure. For most coals with high concentrations of As, the As is associated with late-stage pyrite mineralization (Kolker et al., 1999). Commonly, this pyrite and the As it contains can be effectively removed by conventional physical coal cleaning procedures (Akers et al., 1997). Additionally, As may be concentrated in coal cleaning and coal combustion waste products in an oxidized, water-soluble form (Huggins, 2002; Huggins et al., 2002). The maximum value of U in Turkish coals reported here is 140 ppm compared to a maximum value of 17 ppm reported by Bragg et al. (1998) for the Gulf Coast lignite region (the Fort Union region maximum is 13 ppm). Uranium in more than 25% of the Turkish samples was greater than the maximum uranium contents for the U.S. lignites, and more than 75% of the Turkish samples have uranium concentrations greater than the average uranium

content of U.S. lignites. Uranium in coal ash from the Turkish lignite samples in this study is as high as 637 ppm. The weighted average of U in samples from the 26 largest mines (16 ppm; Table 7) is 25% higher than the numerical average of the 26 largest mines which is about the same as the average of all 143 samples. High levels of uranium can present a variety of health problems (ATSDR, 2003). Although there are no known health impacts due to radioactivity from coal or coal combustion products (Zielinski and Finkelman, 1997), the substantially higher concentrations of U in the Turkish coals increase the chances of radiation exposure should the ash not be handled properly. Table 6 shows that the average Sb concentration in Turkish coals (2.7 ppm) is three times higher than the average Gulf Coast lignites (0.87 ppm) and is more than six times higher than the average Fort Union lignites (0.39 ppm). All concentrations of Sb greater than the U.S. maximum were in the Aegean Region (see Regional variations below). The weighted average of Sb for the 26 largest mines (2.0 ppm; Table 7) is about 25% less than the average for all 143 samples. Exposure to antimony at high levels can result in a variety of adverse health effects (ATSDR, 2003). It is unlikely that the elevated concentrations of Sb found in the Turkish coals would cause adverse health effects. However, burning coals with Sb concentrations as high as the 2347 ppm found by Karayigit et al. (2000b) in drill core samples in the Golker coalfield in the Aegean Region may lead to sufficiently high levels of Sb exposure to cause heath problems. The mean concentration of Mo in Turkish lignites is 9.8 ppm compared to 3.8 ppm for the Fort Union region and 2.0 ppm for the Gulf Coast region. On an ash basis, the average Mo concentration in Turkish coals is higher than the Gulf Coast region, but not higher than the Fort Union region. Thirty-six percent of the Mo values in the Turkish lignites are greater than 10 ppm, whereas less than 1% of the samples from the U.S. lignite regions were greater than 10 ppm Mo. The weighted average of Mo for the 26 largest mines (12 ppm; Table 7) is the same as the numerical average of the 26 largest mines and about 25% higher than the average of all 143 samples.

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The mean, median, and maximum concentrations of Hg in Turkish lignites are less than those in U.S. lignite regions (Table 6). On an equal Btu basis, Hg input loadings for the Turkish lignites (14.9 lb/1012 Btu or 6.4 kg/PJ) are also lower than the input loadings for U.S. lignite regions (27 lb/1012 Btu or 11.6 kg/PJ, Gulf Coast region; and 15.9 lb/1012 Btu or 6.8 kg/PJ, Fort Union region), but are slightly higher than the average of U.S. coals (14 lb/1012 Btu or 6.0 kg/PJ; Tewalt et al., 2001). Mercury is the only element that is currently being considered for regulation in the U.S. (EPA Fact Sheet, 2000). The concentrations of Cs and V are significantly greater in the Turkish coals than in the U.S. lignite regions and the weighted average of V for samples taken from the 26 largest mines (119 ppm; Table 7) is nearly twice the average of all 143 samples. There is relatively little data on Cs from U.S. lignite regions (50 analyses from the Gulf Coast Region and none from the Fort Union region). The mean concentration of Cs in each of the Turkish regions is 2 –20 times greater than for the U.S. Gulf Coast lignites, with the mean value for all of Turkey being 10 times greater than mean Cs in the Gulf Coast lignites. The mean value of V in all of Turkish samples is 6 times greater than the corresponding mean value reported for U.S. lignite-producing regions. On an ash basis, the average concentrations of all the other elements in Turkish coals are similar to, or less than, their corresponding values in the U.S. lignite regions (see Table 6). The weighted averages of Ba, Li, Nb, and Se in the 26 largest mines were higher and the weighted average of Ge in the 26 largest mines was lower than the averages for all 143 samples. The large difference of Se (6.2 weighted average compared to an average of 2.2 for all 143 samples; Table 7) was primarily due to a sample from one mine that contained 17 ppm. 5.2.2.2. Metal enrichment. The anomalous enrichments of Ni, Cr, As, Sb, and V in Turkish coals may be related to the widespread occurrence of ore deposits containing this suite of elements. The Tethian ophiolite belt is one of the longest in the world and stretches from Spain to the Himalayas (Bozkurt and Mittwede, 2001). It shows its maximum development in Turkey which contains large and numerous deposits of chromite, Ni-rich olivine, and serpentine.

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Thousands of major and minor chromite deposits are associated with peridotites containing Ni-rich olivine or serpentine and form three major belts aligned along east –west Alpine orogenic zones (Billor and Gibb, 2002). Although arsenic and other metals are associated with ophiolites (Cina, 1990) and related massive sulfide deposits (Gulec and Erler, 1983), Turkey is also the site of extensive Sb – As – Tl– Ba deposits of hydrothermal-sedimentary origin. These deposits are especially developed in Western Anatolia where they are mined for Sb (Jankovic, 1982). Although it is beyond the scope of this study to determine the source of the trace elements, it is likely that development of Turkish lignites in proximity to widespread ore deposits has led to their anomalous enrichment. 5.2.2.3. Regional variations. Although the data are too sparse to warrant detailed discussion of inter- and intra-basin variations, some trends are apparent. Although the average Ni concentration increases from north to south in western Turkey and the Ni values are high in the Mediterranean Region (also South Marmara Region), there is enough scatter in the data to cast doubt as to whether this trend is significant. In fact, nonparametric statistical analysis (Table 4) suggests that the South Marmara Region has a significantly lower average rank value of Ni concentrations than does the North Marmara Region. The box and whisker plots for Ni (Fig. 5) provide data to explain the low Ni averages. Because of two very high outliers, the average concentration of Ni in the South Marmara Region is the third highest overall. Excluding outliers, the average concentration of Ni in the South Marmara Region is the lowest of all regions (see Table 4). The Central Anatolian region and the Eastern Anatolian regions (all central regions) have lower average concentrations of Ni than the Mediterranean and Black Sea regions. The regional average for Cr ranges from 16 to 99 ppm. In western and eastern Turkey, the average Cr concentration increases from north to south. However, this trend is not observed in the central part of the country. Table 4 shows that the average of the Cr concentrations in the Aegean Region in southwestern Turkey is significantly higher than those of all other regions in Turkey except for the Mediterranean and the Eastern Anatolian regions.

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Fig. 5. Box and whisker plot of Ni on a dry basis. Circles represent outliers, error bars are at the 10th and 90th percentile; the boxes contain values between the 25th and 75th percentile and the line in the box represents the median.

The regional averages for As are 30 –140 ppm with a maximum of 620 ppm. Like Cr and Ni, As generally increases from north to south in Western Turkey. In six of the seven regions investigated, at least one sample had an As concentration greater than 180 ppm. The concentration of As in the samples from the North Marmara Region (averaging only 30 ppm) and the Mediterranean Region (averaging 44 ppm) are substantially less than the concentration of As in other regions, except for the Black Sea Region (averaging 59 ppm). When considered in terms of average rank value, these differences are statistically significant at the 0.05 significance level. The Black Sea Region is not significantly different from any of the other regions (see Table 4) with regard to average rank values of As. Average U concentrations generally increase from northern Turkey to southern Turkey. The U concentrations in North Marmara and the Black Sea regions are not significantly different from each other relative to average rank value of U concentrations, nor are the Aegean and Central Anatolia regions significantly

different from each other. Both the North Marmara and the Black Sea regions have statistically lower average rank values of U than the Aegean and Central Anatolian regions. The average Sb concentration in the Aegean Region (4.6 ppm) is higher than the maximum value in any of the other regions. All of the high (>4 ppm) Sb coals can be found in this region. Karayigit et al. (2000b) report Sb concentrations up to 2347 ppm (averaging 134 ppm) in the Golker coalfield in the Aegean Region. The highest Sb value observed in the present study (41 ppm) was in a sample from a mine near that location. The average rank values of Cs concentrations in samples from the Aegean and South Marmara regions are significantly higher than those in the other regions, except for the East Anatolian region, which has an average rank value of Cs concentrations that is not significantly different from that of any other region except the Black Sea region. In addition, the samples from the Black Sea region, the region having the lowest mean concentration (0.93 ppm) of Cs, have a

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115

significantly lower average rank value of Cs concentrations than the samples from the North Marmara region (see Table 4).

6. Conclusions There is an abundant supply of coal (mostly lignite and subbituminous) in Turkey that can be used for electric power generation. Total reserves of over 8 billion tons should help provide increasing power capacity for years. Generally, these coals have traceelement concentrations similar to those of U.S. lignites. However, the mean concentrations of Ni, Cr, As, U, Sb, Cs, and V in Turkish coals are higher than in U.S. lignites. Except for Cs and V, these elements are all considered to be potentially hazardous air pollutants and the exceptionally high values of some of these elements in Turkish coals warrant further study to determine potential environmental and health risks. The concentration of Hg is slightly lower on average in Turkish coals than in U.S. lignites, but the average concentration on a lb/Btu basis is similar to that in U.S. coals. Although major elements and ash yield are generally higher on average in the Anatolian regions, elemental concentrations for the most part do not vary greatly between geographic regions and there are few trends that can be established for the trace elements.

Appendix A . Instructions The on-line Appendix A consists of eight parts (A-1 through A-8) which contain the supporting data for this paper. In addition, there is a brief description of each of the eight parts to the appendix and an index with links to all pages in Appendices A-1 through A-8. Words in blue (usually underlined) are links and clicking with a mouse driver on them will take the reader to that page. In all cases, the reader can return to the page he started from by clicking the back arrow in Acrobat [this is the arrow with a tail on it ( p ); the back arrow without the tail (Y) will take the reader to the previous page in the document which is generally not the location from which the reader originally linked]. In order to make the text more legible, it may be necessary to change the

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magnification for the page. This can be done by using the + or buttons on the toolbar, changing the percent size in that same bar, using zoom in or zoom out under View of the pop down menu bar or using the zoom in or zoom out tool (looks like a magnifying glass). There are three types of data in the appendices: tables, charts and descriptive information including cover sheets for each appendix. Each cover sheet has a link to the beginning of the tables in the appendix, to the index and to the description of the appendix. The charts are accessible from the index as well as from a table in the appropriate appendix. Generally clicking anywhere on the chart, except for the link to the key, will return the reader to the table from which the data were generated. To return to the index, the reader should use the back arrow or at or near the bottom of every page in the tables is a link to the appendix index page linking to that page of data. References Akers, D.J., Raleigh Jr., C.E., Lebowitz, H.E., Ekechukwu, K., Aluko, M.E., Arnold, B.J., Palmer, C.A., Kolker, A., Finkelman, R.B., 1997. HAPs-Rxk: Precombustion Removal of Hazardous Air Pollutant Precusors, DOE Report No. DEAI22-97245, pp. 1 – 6. ASTM, 2003. Annual Book of ASTM Standards, 2003. Gaseous Fuels; Coal and Coke, vol. 05.06. American Society for Testing Materials, West Conchohacken, PA. ATSDR, 2003, ToxFAQs. http:www.atsdr.cdc.gov/tfaq15.html, Agency for Toxic Substances and Disease Registry CAS# 7330-02-0. (Ni), 7440-36-0, (Sb), 7440-61-1 (U). Also available as a CD as Tox Profiles 2003. U.S. Department of Health and Human Services, Public Health Services, Agency for Toxic Substances and Disease Registry, Division of Toxicology. Ayanogˇlu, S.F., Gunduz, G., 1978a. Neutron activation analysis of Turkish coals; I, Elemental contents. Journal of Radioanalytical Chemistry 43 (1), 155 – 157. Ayanogˇlu, S.F., Gunduz, G., 1978b. Neutron activation analysis of Turkish coals; II, Analysis of ashes and the effects of burning conditions on percent transference. Journal of Radioanalytical Chemistry 43 (1), 159 – 164. Ayanogˇlu, S.F., Gunduz, G., 1978c. Neutron activation analysis of Turkish coals; III, Relation between composition of coal and local earth crust. Journal of Radioanalytical Chemistry 43 (1), 165 – 167. Batı, Z., 1996. Palynostratigraphy and Coal Petrography of the Upper Oligocene Lignites of the Northern Thrace Basin, NW Turkey, Middle East Technical University. PhD thesis, Ankara, Turkey.

114

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115

Bencko, V., Symon, K., 1977. Health aspects of burning coal with a high arsenic content: II. Hearing aspects of burning coal with high arsenic content. Environmental Research 13, 386 – 395. Billor, M.Z., Gibb, F., 2002. The mineralogy and chemistry of the chromite deposits of southern (Kizildag, Hatay, and Islahiye, Antep) and Tauric ophiolite belt (Pozanti-Karsanti, Adana), Turkey. Abstracts, 9th International Platinum Symposium, July 21 – 25, 2002, Billings, Montana, unpaginated. Bozkurt, E., Mittwede, S.K., 2001. Introduction to the geology of Turkey—a synthesis. International Geology Review 43, 578 – 594. Bragg, L.J., Oman, J.K., Tewalt. S.J., Oman, C.L., Rega, N.H., Washington, P.M., Finkelman, R.B., 1998. U.S. Geological Survey Coal Quality (COALQUAL) Database: Version 2.0 CD-ROM. Also http://energy.er.usgs.gov/products/databases/ CoalQual/intro.htm. Bingo¨l, E., 1998. Tu¨rkiye Jeoloji Haritası (Scale: 1/2 000 000). Briggs, P.H., 1997. Determination of 25 elements in coal ash from 8 Argonne Premium Coal samples by inductively coupled argon plasma-atomic emission spectrometry. In: Palmer, C.A. (Ed.) The chemical analysis of Argonne Premium Coal samples. U.S. Geological Survey Bulletin 2144, pp. 39 – 43. Also http:// pubs.usgs.gov/bul/b2144/25.htm. de Bruijn, H., Sarac¸, G., 1991. Early Miocene rodent faunas from the eastern Mediterranean area. Part I. The genus Eumyarion. Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen 94 (1), 1 – 36. de Bruijn, H., Sarac¸, G., 1992. Early Miocene rodent faunas from the eastern Mediterranean area Part II. Mirabella (Paracricetodontinea, Muroidea). Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen 95 (1), 25 – 40. de Bruijn, H., Daam, R., Daxner-Ho¨ck, G., Fahlbush, V., Gınsburg, P., Mein, P., Morales, J., 1992. Report of the RCMNS working group on fossil mammals, Reisenburg 1990. Newsletters on Stratigraphy 26 (2 – 3), 65 – 118. ¨ nay, E., 1993. Early Miode Bruijn, H., Fahlbush, V., Sarac¸, G., U cene rodent faunas from the eastern Mediterranean area. Part III. The genera Deperetomya and Cricetodom with a discussion of evolutionary history of the Cricetodontini. Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen 96, 151 – 216. de Bruijn, H., Sarac¸, G., van den Ostende, L.W., Roussiakr, S., 1999. The status of the genus name Parapodemus SCHAUB, 1938; new data bearing on an old controversy. Deinsea – Annals of the Natural History Museum, Rotterdam 7, 95 – 112. Bullock Jr., J.H., Cathcart, J.D., Betterton, W.J., 2002. Analytical methods utilized by the United States Geological Survey for the analysis of coal and coal combustion by-products. U.S. Geological Survey Open-file report 02-389. Also http://pubs.usgs.gov/ of/2002/ofr-02-389/. Cina, A., 1990. Sulphide and arsenide mineralization with the basic and ultrabasic rocks of Albanian ophiolites. In: Malpas, Panayiotou, Panayiotou, Xenophontos (Eds.), Ophiolites; Oceanic Crustal Analogues; Proceedings of the Symposium ‘‘Troodos 1987’’. Minist. Agric. and Nat. Resour., Nicosia, Cyprus, pp. 615 – 626.

Conover, W.J., 1999. Practical Nonparametric Statistics, 3rd ed. Wiley, New York, pp. 288 – 297. Demirok, Y., Uc¸akc¸ıogˇlu, A., 1993. Du¨nya’da ve Tu¨rkiye’de ¨ ranyum Rezervleri Linyit, Asfaltit, Tas¸ ko¨mu¨r, Bitu¨mlu¨ s¸ist, U ¨ retimleri. MTA, Fizibite Etu¨tleri Dairesi yayını (in Turkve U ish) Ankara. EIA, 2003. Turkey, Country Energy Data Report. http://www.iea. doe.gov/emeu/world/country/cntry_TU.html. EPA Fact Sheet, 2000. EPA to Regulate Mercury and other Air Toxics Emissions from coal- and oil-fired Power Plants. http:// www.epa.gov/ttn/oarpg/t3/factsheets/fsutil.pdf. Finkelman R.B., 2000. Health Impacts of Coal Combustion. U.S. Geological Survey Fact Sheet FS-094-00. Also http://pubs. usgs.gov/FS/fs94-00. Finkelman, R.B., Warwick, P.D., Pierce, B.S., 2001. The World Coal Quality Inventory (WoCQI). U.S. Geological Survey Fact Sheet FS-155-00. Also http://pubs.usgs.gov/FS/fs94-00. Finkelman, R.B., Orem, W., Castranova, V., Tatu, C.A., Belkin, H.E., Zheng, B., Lerch, H.E., Maharaj, S.V., Bates, A.L., 2002. Health impacts of coal and coal use: possible solutions. International Journal of Coal Geology 50, 425 – 443. ¨ z, D., Tuncalı, E., 1993. Go¨kmen, V., Memikogˇlu, O., Dagˇlı, M., O Tu¨rkiye Linyit Envanteri. MTA Publication, Ankara, p. 356 in Turkish. Go¨ru¨r, N., S¸engo¨r, A.M.C., Okay, I˙.A., Tu¨ysu¨z, O., Sakınc¸, M., ¨ zgu¨l, N., Genc¸, T., (I˙TU ¨ Maden Yigˇitbas¸, E., Akko¨k, R., O Fak. Genel Anabilimdalı, Tu¨bitak Global Tektonik Aras¸tırma ¨ lc¸en, S., Ercan, T., Akyu¨rek, B., S¸arogˇlu, F., ¨ nitesi), O U 1998a. Triassic to Miocene Palaeogeographic Atlas of Turkey. MTA Genel Mu¨du¨rlu¨gˇu¨, Ankara. Go¨ru¨r, N., Taysaz, O., Sengor, A.M.C., 1998b. Tectonic evolution of the Central Anatolian basins. International Geological Review 40 (9), 831 – 850. Gulec, N., Erler, A., 1983. Trace elements characteristics of pyrites in sulfide massive deposits of Turkey and Cyprus. Bulletin of the Geological Society of Turkey 26 (2), 145 – 152. Hoeft, A.P., Luppens, J.A., Fuller, R.I., Tucker, C.R., 1983. Coal analysis data interrelationships and crossplots. Coal Testing Conference: Proceedings of the 3rd Conference, vol. III. Charleston, WV, pp. 95 – 100. Huggins, F.E., 2002. Overview of analytical methods for inorganic constituents in coal. International Journal of Coal Geology 50, 169 – 214. Huggins, F.E., Huffman, G.P., Kolker, A., Mroczkowski, S.J., Palmer, C.A., Finkelman, R.B., 2002. Combined application of XAFS spectroscopy and sequential leaching for determination of arsenic speciation in coal. Energy and Fuels 16 (5), 1167 – 1172. Hwang, J.D., Wang, W.-J., 1994. Determination of hexavalent chromium in environmental fly-ash samples by an inductively coupled plasma-atomic emission spectrometer with ammonium-ion complexation. Applied Spectroscopy 48 (9), 1111 – 1117. ISO, 1997. Solid mineral fuels—determination of ash, International Organization of Standards, 75.160.10 1171-97. Jankovic, S., 1982. Sb – As – Tl – Ba mineral assemblage of hydrothermal-sedimentary origin, Gu¨m u¨sko¨y deposit, Ku¨tahya (Tur-

C.A. Palmer et al. / International Journal of Coal Geology 60 (2004) 85–115 key). In: Amstutz, C.G., El Goresy, A., Frenzel, G., Kluth, C., Moh, G., Wauschkuhn, A., Zimmermann, R.A. (Eds.), Ore Genesis: The State of the Art. Springer-Verlag, Berlin, pp. 143 – 149. Karayigit, A.I., Akgun, F., Gayer, R.A., Temel, A., 1999. Quality, palynology, and palaeoenvironmental interpretation of the Ilgin Lignite, Turkey. International Journal of Coal Geology 38 (3 – 4), 219 – 236. Karayigit, A.I., Gayer, R.A., Querol, X., Onacak, T., 2000a. Contents of major and trace elements in feed coals from Turkish coal-fired power plants. International Journal of Coal Geology 44 (2), 169 – 184. Karayigit, A.I., Spears, D.A., Booth, C.A., 2000b. Antimony and arsenic anomalies in the coal seams from the Gokler Coalfield, Gediz, Turkey. International Journal of Coal Geology 44 (1), 1 – 17. Karayigit, A.I., Spears, D.A., Booth, C.A., 2000c. Distribution of environmental sensitive trace elements in the Eocene Sorgun coals, Gediz, Turkey. International Journal of Coal Geology 42 (4), 297 – 314. Kolker, A., Goldhaber, M.B., Hatch, J.R., Meeker, G.P., Koeppen, R.P., 1999. Arsenic-rich pyrite in coals of the warrior field, northwestern Alabama: mineralogical evidence for a hydrothermal origin. Geological Society of America, Abstracts with Programs 31 (7), A-402 (GSA Annual Meeting, Denver, October, 1999). Lebku¨ chner, R.F., 1974. Orta Trakya Oligosen’inin jeolojisi hakklnda. MTA Dergisi 83, 129 (in Turkish). Luppens, J.A., 1982. Experience with the application of the equilibrium moisture test to lignite. Coal Testing Conference: Proceedings of the 2nd Conference, vol. II. Charleston, WV, pp. 1 – 6. Lu¨ttig, G., Steffens, P., Becker-Platen, J.D., Benda, I., Irrlitz, W., Sickkenberg, O., Staesche, U., 1976. Paleogeographic Atlas of Turkey. Explanatory Notes. Bundesanstalt fu¨r Geowissenschaften und Rohstoffe, Hanover. Lynch, R., 2003. An energy overview of the Republic of Turkey. U.S. Department of Energy. http://www.fe.doe.gov/international/ turkover.html. Meier, A.L., 1997. Determination of 33 elements in coal ash from 8 Argonne Premium Coal samples by inductively coupled argon plasma-mass spectrometry. In: Palmer, C.A. (Ed.), The Chemical Analysis of Argonne Premium Coal Samples. U.S. Geological Survey Bulletin 2144, 45 – 50. Also http://pubs.usgs.gov/ bul/b2144/33.htm. Miller, J.C., Miller, N.N., 1984. Statistics for Analytical Chemistry. Ellis Horwood, Chichester, pp. 70 – 71. O’Leary, R.M., 1997. Determination of Mercury and selenium in eight Argonne Premium Coal samples by cold-vapor and hydride-generation atomic absorption spectrometry. In: Palmer, C.A. (Ed.), The Chemical Analysis of Argonne Premium Coal Samples. U.S. Geological Survey Bulletin 2144, 51 – 56 Also. http://pubs.usgs.gov/bul/b2144/mercury.htm. Ott, R.L., Longnecker, M., 2001. An Introduction to Statistical Methods and Data Analysis, 5th ed. Duxbury, Pacific Grove, CA, p. 97.

115

Orem, W.H., Holmes, C.W., Kendall, C., Lerch, H.E., Bates, A.L., Silva, S.R., Boylan, A., Corum, M., Marot, M., Hedgman, C., 1999. Geochemistry of Florida Bay sediments: nutrient history at five sites in eastern and central Florida Bay. Journal of Coastal Research 15 (4), 1055 – 1071. Palmer, C.A., 1997. Determination of 29 elements in coal ash in 8 Argonne Premium Coal samples by instrumental neutron activation analysis. In: Palmer, C.A. (Ed.), The Chemical Analysis of Argonne Premium Coal Samples. U.S. Geological Survey Bulletin 2144, 25 – 32. http://pubs.usgs.gov/bul/b2144/ 29.htm. Palmer, C.A., Tuncali, E., Finkelman, R., 1999. The distribution of trace elements in Turkish lignites western Anatolia and the Thrace Basin. Proceedings, Sixteenth Annual International Pittsburgh Coal Conference and Workshop. PDF file on CD-ROM. Querol, X., Whateley, M.K.G., Fernandez-Turiel, J.L., Tuncalı, E., 1997. Geochemical controls on the mineralogy and geochemistry of the Beypazarı lignite, central Anatolia, Turkey. International Journal of Coal Geology 33 (3), 255 – 271. Querol, X., Atastuey, A., Plana, F., Lopez-Soler, A., Tuncalı, E., Toprak, S., Ocakog˘lu, F., Ko¨ker, A., 1999. Coal geology and coal quality of the Miocene Mug˘la basin, southwestern Anatolia Turkey. International Journal of Coal Geology 41, 311 – 332. Sarac¸ , G., 1987. Kuzey Trakya Bo¨lgesinde Edirne-Klrklareli, Saray-C ¸ orlu, Uzunko¨pru¨Dereikebir Yo¨relerinin Memeli Paleo¨ .Fen Bilimleri Enstitu¨su¨ Yu¨ksek Lisans Tezi. Jeofaunasl. A.U loji Mu¨ hendisligˇi Anabilimdall (in Turkish), pp. 1 – 110, Ankara (Yaynlanmamıs¸). Sheps, S., Finkelman, R.B., Councell, T.B., Cohen, H., 1999. Leaching of chromium from coal fly ash: European coal geology. In: Nakoman, E. (Ed.), Proceedings of the 3rd European Coal Conference, pp. 475 – 480. SigmaPlot, 2002. SigmaPlot 8.0 User’s Guide SPSS, Chicago. Tewalt, S.J., Bragg, L.J., Finkelman, R.B., 2001. Mercury in U.S. coal—Abundance, distribution, modes of occurrence, USGS Fact Sheet FS-095-01. Tuncalı, E., Ocakogˇlu, F., 1995. Tu¨rkiye’nin Ko¨mu¨r Potansiyeli, Rezervleri ve 21. Yu¨zYllda Ko¨mu¨r. Ko¨mu¨r Teknolojisi ve Kullanlml Semineri III (in Turkish), 13 – 14 Ekim, Yurt Madenciligˇini Gelis¸tirma Vakfı Yayınları, Ankara, pp. 19 – 26. Tuncalı, E., C ¸ iftci, B., Yavuz, N., Toprak, S., Ko¨ker, A., Gencer, Z., Ayc¸ık, H., Pahin, N., 2002. Chemical and Technological Properties of Turkish Tertiary Coals. (MTA Maden Tetkek ve Arama Genel Mu¨du¨rIu¨gu¨) Ankara. ¨ nay-Bayraktar, E., 1989. Rodents from the Middle Oligocene of U Turkish Thrace, Utrecht Micropaleontological Bulletins. Special Publication, No. 5, pp. 1 – 119. OMI-GB, Utrecht. Vaninetti, G.E., Busch, C.F., 1982. Mineral analysis of ash data: A utility perspective. The Journal of Coal Quality 1 (2), 22 – 31. Zielinski, R.A., Finkelman, R.B., 1997. Radioactive Elements in Coal and Fly Ash: Abundance, Forms, and Environmental Significance, U.S Geological Survey Fact Sheet FS-163-97. Also http://greenwood.cr.usgs.gov/energy/factshts/163-97/ FS-163-97.html.