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Luminescence chronology of aeolianites from the section at Givat Olga — Coastal Plain of Israel
Quaternary Science Reviews 20 (2001) 805}809
Luminescence chronology of aeolianites from the section at Givat Olga * Coastal Plain of Israel夽 Manfred Frechen *, Birgit Dermann, Wolfgang Boenigk, Avraham Ronen Centre for Environmental Change and Quaternary Research, GEMRU, Cheltenham and Gloucester CHE, Francis Close Hall, Swindon Road, Cheltenham, GL50 4AZ, UK Geologisches Institut, Universita( t zu Ko( ln, Zu( lpicher Str. 49a, D-50674 Ko( ln, Germany The Zinman Institute of Archaeology, The University of Haifa, Haifa 31905, Israel
Abstract The Eastern Mediterranean Coastal Plain of Israel is composed mainly of loam, sand and gravel of Pleistocene to Holocene age, indicating an alternation of marine, coastal and continental environments. Owing to the complexity of the numerous exposures of aeolianites (`kurkara) and soils (`hamraa) in the elongated ridges along the coastal plain, it is di$cult to set up a reliable stratigraphy. A systematic luminescence dating study was carried out on loose sand, kurkar and hamra deposits in the coastal plain between Netanya and Haifa. Sixteen samples were taken and investigated from the section at Givat Olga. The chronological results show excellent agreement between the infrared optically stimulated luminescence (IRSL) and thermoluminescence (TL) techniques, indicating that the former sand dunes were well-bleached prior to deposition. The IRSL and TL age estimates range from about 75}3 ka for the aeolianites indicating that this kurkar ridge formed during an older period of the last glaciation, likely before 50 ka. 2000 Elsevier Science Ltd. All rights reserved.
1. Introduction The Eastern Mediterranean Coastal Plain of Israel is composed mainly of alternating sand, soil and gravel of Pleistocene to Holocene age, indicating an alternation of marine, coastal and continental environments. The carbonate-rich aeolianites (`kurkara) and the intercalated palaeosols (`hamraa) with their archaeological "nd horizons are an important archive of climatic change and environment in the study area. The aeolianites form ridges (`kurkar ridgesa) which run parallel to the Mediterranean coast (Fig. 1). These kurkar ridges are formed by a typical distribution of longitudinal sand dunes indicating a dominant wind direction perpendicular to the coast. The sand is transported from the Nile delta by Eastern Mediterranean currents eastwards and northwards along the coast of Sinai and Israel. The sand is migrating inland forming di!erent types of dunes. The mineral spectra of the aeolianites are dominated by quartz and some minor feldspar (Goldsmith and Golik, 1980). 夽
Paper published in December, 2000. * Corresponding author. Tel.: 01242-54-4091; fax: 01242-532-997. E-mail address: [email protected] (M. Frechen).
Owing to the complexity of the numerous exposures of kurkar and hamra deposits in the elongated ridges along the coastal plain, it is di$cult to set up a reliable stratigraphy. Ronen (1975) distinguished eight palaeosols, which are intercalated into the kurkar deposits of the Coastal Plain. Five palaeosols furnish artifacts covering the Lower Palaeolithic to the Mesolithic and indicating a cyclical change in periods of aridity and phases of habitation (higher precipitation). Gvirtzman et al. (1984) correlated the kurkar and hamra formation with high and low sea level, respectively, whereas Brunnacker et al. (1982) and Boenigk et al. (1985) correlate the hamra formations with high sea level. Yaalon (1967) questioned the simple correlation of kurkar and hamra sequences with the cold and warm cycles of the marine record on the basis of the oxygen isotope stages. Gvirtzman et al. (1998) no longer correlate between high sea stands and the formation of kurkars. The intensity of soil formation depends on the availability of rain water. Periods with high precipitation result in the complete dissolution of carbonates and the formation of hamras, which are carbonate-free (Yaalon and Dan, 1967). Periods of moderate precipitation result in a part solution of carbonate, as evidenced by carbonate nodules in the soil (Wieder and Yaalon, 1974), hence
0277-3791/01/$ - see front matter 2000 Elsevier Science Ltd. All rights reserved. PII: S 0 2 7 7 - 3 7 9 1 ( 0 0 ) 0 0 0 3 6 - 6
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M. Frechen et al. / Quaternary Science Reviews 20 (2001) 805}809
in the stabilization of sand dunes and the formation of a thin crust of sandy regosol (`cafeH -au-laita soil type), e.g. at the top of the Nahsholim sands and two regosols intercalated within the Ta'arukha sands. The climatic and environmental e!ect of the availability of bioclastic sediments in the littoral zone is still unclear. It is likely that the bioclastic material was available in the littoral zone during the formation of the Ramat Gan, Dor and Tel Aviv kurkars (Gvirtzman et al., 1998). The Nahsholim, Ta'arukha and Hadera sands were not cemented because bioclastic material was not available in the littoral zone or within the aeolianites. In the Carmel Coast, the only periods of high precipitation are linked with the Middle Palaeolithic soil and the Epi-Palaeolithic soil (Ronen, 1975). The section at Givat Olga, probably a former outlet of Nahal Hadera, is situated at the coastal cli! of the northern end of the Sharon Coastal Plain and close to the southern end of the Carmel Plain (Fig. 1). The more than 17 m thick sequence is composed of four lithological units: kurkar, hamra complex, carbonaceous sandstone (`plataa) and loose sand dunes from the bottom to the top (Fig. 2). The section at Givat Olga has not yielded #int artifacts, but a small distance inland a few wellpreserved, in situ Epi-Palaeolithic sites embedded in red loam clearly indicate an late-Pleistocene age of this loam (Ronen et al., 1975, Hefziba; Ronen and Kaufman, 1976, Hadera I and II; Gopher, pers. comm., Hadera V.). In order to get a more reliable chronological framework, sixteen samples were taken from the section at Givat Olga and investigated by luminescence dating, resulting in 31 infrared optically stimulated luminescence (IRSL) and thermoluminescence (TL) age estimates. This study is a part of a high-resolution systematic luminescence dating study carried out on kurkar and hamra deposits in a north}south transect of the coastal plain between Netanya and Haifa (see also Engelmann et al., 2001).
2. Methodology
Fig. 1. Map showing kurkar ridges between Netanya and Haifa and the location of the section at Givat Olga, Israel.
The samples were taken as 3}5 kg specimens or in light-tight cylinders in the "eld. The outer light-exposed part of the specimen was removed under subdued light in the laboratory and used for gamma spectrometry. The aeolianites were prepared for luminescence analysis by removing the carbonate in 17% hydrochloric acid, by sieving to separate the 100}200 lm grain-size fraction, followed by treatment with 0.01 n sodium oxalate and 30% hydrogen peroxide to remove clay coatings and organic matter, respectively. The remaining material was sieved again to separate the 100}125 lm grain-size fraction. Potassium feldspar and quartz minerals were extracted from all samples by heavy liquid separation with sodium
M. Frechen et al. / Quaternary Science Reviews 20 (2001) 805}809
807
a TL/OSL Ris+ reader (TL-DA-15) at the Cheltenham Geochronology Laboratories. A "lter combination of Schott BG-39 and Corning 7-59 was placed between the photomultiplier and the aliquots, for both IRSL and TL measurements. After 25 s of IR exposure (880$80 nm), the same discs were heated immediately to obtain their TL at a heating rate of 53C/s up to 4503C. Second glow normalization was applied in order to reduce the discto-disc scatter for both IRSL and TL. Equivalent doses were obtained by integrating the 10}25 s region of the IR decay curve and the 300}4003C region of the TL glow curve for the additive dose method. An exponential growth curve was "tted for the di!erent dose steps and the natural luminescence signal and extrapolated to zero, to estimate the equivalent dose using the software developed by Rainer GruK n, Canberra. Dose rates for all samples were obtained from potassium, uranium and thorium contents, measured by gamma spectrometry in the laboratory, assuming a water content of 5$2.5% for the kurkar and carbonaceous sandstone and 9$3% for the hamra. A radioactive equilibrium was assumed as well. The potassium content of the alkali feldspars was determined by thick source beta counting, ranging from 3.2$0.3 to 7.1$0.7%. However, the alkali feldspar separation was rather poor, owing to a contamination with quartz, hence a value of 12.5$2% was taken for the potassium content in feldspar for each sample, as suggested by Huntley and Barril (1997). A correction was calculated for the attenuation of the cosmic dose rate with depth (cf. Aitken, 1985). Fading experiments have not indicated any signi"cant fading under the present technique.
3. Results
Fig. 2. Lithological sequence and position of the samples, geological description and IRSL and TL age estimates for the section at Givat Olga.
polytungstate (2.58, 2.62 and 2.70 g/cm). The potassium feldspar grains were "xed on aluminium discs and successively irradiated in at least six di!erent dose steps by a Co-60 gamma source with a dose rate of 7.8 and 8.0 Gy min\ depending on the sample position. Two weeks after irradiation and storing at room temperature, the samples were preheated on a heating plate at 1603C for 16 h, followed by more than 6 weeks, storage at room temperature. The samples were measured using
Dosimetric results are listed in Table 1, as determined by gamma spectrometry. A radioactive disequilibrium within the U-238 decay chain, caused by radon loss, was not detectable by gamma spectrometry measuring and comparing the Ra-226 and Pb-215 energy peaks. The mean total dose rate is 1.08 Gy/ka ranging from 0.90 to 1.30 Gy/ka for the kurkar, carbonaceous sandstone and loose aeolian sands. The mean dose rate of the samples from the hamra is 1.35 Gy/ka ranging from 1.07 to 1.60 Gy/ka. The equivalent dose values increase with depth from 3.4$0.4 to 128.5$24.4 Gy and from 3.0$0.5 to 103.3$5.1 Gy for IRSL and TL, respectively, indicating four main data clusters (Table 1). The luminescence age estimates are discussed with respect to the four lithological units from the bottom to the top: (a) Kurkar, (b) Hamra complex, including Epi-Palaeolithic soil,
66.5$5.8 74.5$6.4 52.9$4.8 61.5$7.4 52.2$5.1
3.3$0.5 4.8$0.5 5.3$0.7 4.1$0.3 5.6$0.7 5.7$0.8 12.3$1.4 14.2$1.6 19.4$2.0 33.0$2.8 41.9$8.2 50.5$9.0 55.7$5.0 54.7$9.1 100.6$20.5 66.9$7.0 98.7$5.0 103.3$5.1 53.2$1.9 78.5$7.4 68.0$4.4
3.0$0.5 3.6$0.3 3.4$0.3 11.1$1.0 4.1$0.7 6.2$0.4 13.3$1.3 23.0$5.6 24.7$2.2 47.9$1.0
3.4$0.4 4.6$0.3 4.8$0.5 4.7$0.2 6.1$0.6 5.8$0.6 14.6$1.2 16.1$1.3 20.8$1.4 53.0$2.9 65.5$12.1 74.9$12.3 77.2$4.3 55.0$8.0 128.5$24.4 87.1$6.6
1.04$0.08 0.95$0.08 0.90$0.08 1.15$0.08 1.08$0.08 1.02$0.08 1.18$0.09 1.13$0.09 1.07$0.09 1.60$0.11 1.57$0.11 1.48$0.10 1.39$0.10 1.01$0.08 1.28$0.09 1.30$0.10
IRSL (ADD) age (ka) Dose rate (Gy/ka) ED TL (ADD) (Gy) ED IRSL (ADD) (Gy)
150.0$5 150.0$5 126.0$5 106.5$5 64.5$5 64.5$5 33.0$5 33.0$5 33.0$5 33.0$5 33.0$5 13.5$5 13.5$5 13.5$5 13.5$5 13.5$5 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 0.3$0.02 0.3$0.02 0.3$0.02 0.3$0.02 0.2$0.02 0.4$0.03 0.5$0.04 0.5$0.04 0.5$0.03 0.8$0.06 0.8$0.06 0.8$0.06 0.7$0.05 0.4$0.03 0.7$0.05 0.7$0.05 0.4$0.03 0.4$0.03 0.4$0.03 0.4$0.03 0.4$0.03 0.4$0.02 0.5$0.04 0.5$0.04 0.5$0.03 0.9$0.06 0.8$0.05 0.7$0.05 0.6$0.04 0.6$0.04 0.6$0.04 0.6$0.04 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG
1.3$0.09 0.9$0.06 0.9$0.06 3.9$0.3 4.2$0.3 1.2$0.08 2.2$0.2 2.0$0.1 1.7$0.1 3.8$0.3 3.3$0.2 2.9$0.2 2.4$0.2 0.8$0.05 1.0$0.07 1.0$0.07
Cosmic radiation dose Internal potassium (%) Potassium (%) Uranium (ppm)
Thorium (ppm)
(c) Carbonaceous sandstone (`plataa), (d) Loose aeolian sands. The kurkar deposits are the oldest unit at the section at Givat Olga. IRSL and TL age estimates range from 66.9$7.0 to 54.7$9.1 and from 61.5$7.4 to 52.2$5.1 ka, respectively (Fig. 2). The IRSL age estimate of OLG2 was not taken into account owing to signi"cant disc-todisc scatter. The lower part of the hamra yielded a similar IRSL age results ranging from 55.7$5.0 to 50.5$9.0 ka. It is likely that the palaeosol superimposed the upper part of the kurkar. Five samples were taken from the upper part of the hamra complex. The IRSL and TL age estimates range from 41.9$8.2 to 11.2$1.4 ka. The loose sand on top of the hamra yielded luminescence age estimates ranging from 6.1$0.6 to 5.7$0.8 ka. The loose sand is covered by well-cemented calcareous sandstone (`plataa). The IRSL age estimates are slightly younger than those of the underlying loose sand ranging from 5.6$0.7 to 4.1$0.3 ka. The youngest sediments, the uppermost loose aeolian sand, yielded IRSL and TL age estimates ranging from 5.3$0.7 to 3.3$0.5 and from 3.8$0.5 to 2.9$0.5 ka, respectively.
4. Discussion and conclusion
Sample
Table 1 Dosimetric and chronological results for section Givat Olga
2.9$0.5 3.8$0.5 3.8$0.5 9.7$1.1 3.8$0.7 6.1$0.6 11.2$1.4 20.3$5.2 23.0$2.7 29.9$2.1
M. Frechen et al. / Quaternary Science Reviews 20 (2001) 805}809 TL (ADD) age (ka)
808
The stratigraphically oldest sediment at section Givat Olga is designated to represent stratigraphically the Ramat Gan kurkar, Nahsholim sand and Dor kurkar (Gvirtzman et al., 1998), which are likely to be an equivalent of kurkar II, see Boenigk et al. (1985). Luminescence dating in the area yielded IRSL age estimates between 64$8 and 48$4 ka for Ramat Gan kurkar, Nahsholim sand and Dor kurkar (Porat and Wintle, 1994), which are in excellent agreement with the IRSL and TL results of this study. The lower part of the hamra at section Givat Olga yielded IRSL age estimates of 55.7$5.0 and 50.5$9.0 ka, which are in agreement with 51$3 and 56$5 ka for the Netanya hamra in the Sharon coast determined by Porat and Wintle (1994) and Ritte et al. (1997). At section Givat Olga, no Middle Palaeolithic artifacts have been found from the lower part of the hamra. The upper brown clayey palaeosol is designated to represent the Epi-Palaeolithic soil. The IRSL age estimates range from 19.4$2.0 to 12.3$1.4 ka for the upper part of this hamra complex, which is in agreement with the time period of Epi-Palaeolithic industries between 20 and 10 ka. The calcareous sandstone (`plataa) is likely to be an equivalent of the Tel Aviv kurkar, which is assumed by the luminescence age estimates ranging from 5.6$0.7 to 4.1$0.3 ka. The "rst IRSL and TL study in the area between Netanya in the south and Haifa in the north yielded
M. Frechen et al. / Quaternary Science Reviews 20 (2001) 805}809
excellent agreement between the luminescence studies on single and multiple aliquot by Porat and Wintle (1994) and Ritte et al. (1997) further south. The following stratigraphic correlation seems to be most likely. Kurkar II (Boenigk et al., 1985) is designated to be an equivalent of the Ramat Gan kurkar (Gvirtzman et al., 1998). At present, it is still unclear whether the Nahsholim sands and the Dor kurkar coincide with kurkar II as well. The Netanya hamra (Gvirtzman et al., 1998) is likely an equivalent of the Epi-Palaeolithic soil (Ronen, 1983). The Tel Aviv kurkar is likely to be an equivalent of the carbonaceous sandstone (`plataa) and kurkar III, assumed by the chronological results. The latter sediments and the loose aeolian sands on top of the section are of Holocene deposition age at the section at Givat Olga. A comparison with the marine oxygen isotope record seems to be too speculative at the present stage. It is likely, that the shoreline kurkar ridge along the Sharon coast formed during an older period of the last glaciation, probably before 50 ka BP. Furthermore, it is probable that the kurkar ridges of the Carmel coast formed synchronously within short periods of maximum 10}15 ka, most likely during 65 and 50 ka BP. At section Givat Olga, the hamra formation, including part of the Middle Palaeolithic and the Epi-Palaeolithic, took place between 60 and 10 ka, whereas dune sand formation (Tel Aviv kurkar, Ta'arukha and Hadera sands) was active during part of the Holocene. Acknowledgements The authors thank the German}Israeli Foundation for funding [Project-No. I132-301.02/95] and Cathryn Sharp, Cheltenham, for drafting Figs. 1 and 2, Frank Chambers and Naomi Porat for improvement of an earlier version of the manuscript. Thanks to ReneH R. Debuyst for his support for Irradiation which was carried out at INAN, UniversiteH catholiques de Louvainla-Neuve, Belgium. References Aitken, M.J., 1985. Thermoluminescence Dating. Academic Press, London. 359 pp.
809
Boenigk, W., Brunnacker, K., Tillmanns, W., Ronen, A., 1985. Die AG olianite in der noK rdlichen KuK stenebene von Israel * Genese. Stratigraphie und Klimageschichte. QuartaK r 35/36, 113}140. Brunnacker, K., Ronen, A., Tillmanns, W., 1982. Die jungpleistozaK nen AG olianite in der suK dlichen KuK stenzone von Israel. Ein Beitrag zur zeitlich-raK umlichen Klimaentwicklung. Eiszeitalter und Gegenwart 32, 23}48. Engelmann, A., Neber, A., Frechen, M., Boenigk, W., Ronen, A., 2001. Luminescence chronology of Upper Pleistocene and Holocene aeolianites from Netanya South * Sharon Coastal Plain, Israel. Quaternary Science Reviews (Quaternary Geochronology) 20, 799}804. Goldsmith, V., Golik, A., 1980. Sediment transport model of the southeastern Mediterranean coast. Marine Geology 37, 147}175. Gvirtzman, G., Netser, M., Katsav, E., 1998. Last-Glacial to Holocene kurkar ridges, hamra soils and dune "elds in the coastal belt of Israel. Israelian Journal of Earth Science 47, 29}46. Gvirtzman, G., Shachnai, E., Bakler, N., Ilani, S., 1984. Stratigraphy of the kurkar group (Quaternary) of the coastal plain of Israel. Geological Survey Israel, Current Research 1983}84, 70}82. Huntley, D.J., Barril, M.R., 1997. The K content of the K-feldspars being measured in optical dating or in thermoluminescence dating. Ancient TL 15, 11}13. Porat, N., Wintle, A.G., 1994. IRSL dating of kurkar and hamra from the Givat Olga Member in the Sharon Coastal Cli!, Israel. Israel Geological Society, Proceedings of the Annual Meeting, 1994, p. 85. Ritte, M., Porat, N., Gvirtzman, G., 1997. Stratigraphy of the coastal cli! of the Sharon environments of deposition and luminescence dating. Israel Geological Society, Proceedings of the Annual Meeting 1997, pp. 92}93. Ronen, A., 1975. The Palaeolithic archaeology and chronology of Israel. In: Wendorf, F., Marks, A.E. (Eds.), Problems in Prehistory: North Africa and the Levant, Dallas, pp. 229}248. Ronen, A., 1983. Late Quaternary sea levels inferred from coastal stratigraphy and archaeology in Israel. In: Masters, P.M., Flemming, N.C. (Eds.) Quaternary Coastlines and Marine Archaeology Towards the Prehistory of Land Bridges and Continental Shelves. London, pp. 293}304. Ronen, A., Kaufman, D., 1976. Epi-palaeolithic sites near Nahal Hadera. Central Coastal Plain of Israel. Tel Aviv 3, 16}30. Ronen, A., Kaufman, D., Gophna, R., Bakler, N., Smith, P., Amiel, A., 1975. The Epi-Palaeolithic site Hefziba. Central Coastal Plain of Israel. QuartaK r 26, 53}74. Wieder, M., Yaalon, D.H., 1974. E!ect of matrix composition on carbonate nodule crystallisation. Geoderma 11, 95}121. Yaalon, D.H., 1967. Factors a!ecting the lithi"cation of eolianite and interpretation of its environmental signi"cance in the coastal plain of Israel. Journal of Sedimentology and Petrology 37, 1189}1199. Yaalon, D.H., Dan, J., 1967. Factors controlling soil formation and distribution in the Mediterranean coastal plain of Israel during the Quaternary. Quaternary Soils, 7th INQUA Congress, 1965, pp. 321}338.
Luminescence chronology of aeolianites from the section at Givat Olga * Coastal Plain of Israel夽 Manfred Frechen *, Birgit Dermann, Wolfgang Boenigk, Avraham Ronen Centre for Environmental Change and Quaternary Research, GEMRU, Cheltenham and Gloucester CHE, Francis Close Hall, Swindon Road, Cheltenham, GL50 4AZ, UK Geologisches Institut, Universita( t zu Ko( ln, Zu( lpicher Str. 49a, D-50674 Ko( ln, Germany The Zinman Institute of Archaeology, The University of Haifa, Haifa 31905, Israel
Abstract The Eastern Mediterranean Coastal Plain of Israel is composed mainly of loam, sand and gravel of Pleistocene to Holocene age, indicating an alternation of marine, coastal and continental environments. Owing to the complexity of the numerous exposures of aeolianites (`kurkara) and soils (`hamraa) in the elongated ridges along the coastal plain, it is di$cult to set up a reliable stratigraphy. A systematic luminescence dating study was carried out on loose sand, kurkar and hamra deposits in the coastal plain between Netanya and Haifa. Sixteen samples were taken and investigated from the section at Givat Olga. The chronological results show excellent agreement between the infrared optically stimulated luminescence (IRSL) and thermoluminescence (TL) techniques, indicating that the former sand dunes were well-bleached prior to deposition. The IRSL and TL age estimates range from about 75}3 ka for the aeolianites indicating that this kurkar ridge formed during an older period of the last glaciation, likely before 50 ka. 2000 Elsevier Science Ltd. All rights reserved.
1. Introduction The Eastern Mediterranean Coastal Plain of Israel is composed mainly of alternating sand, soil and gravel of Pleistocene to Holocene age, indicating an alternation of marine, coastal and continental environments. The carbonate-rich aeolianites (`kurkara) and the intercalated palaeosols (`hamraa) with their archaeological "nd horizons are an important archive of climatic change and environment in the study area. The aeolianites form ridges (`kurkar ridgesa) which run parallel to the Mediterranean coast (Fig. 1). These kurkar ridges are formed by a typical distribution of longitudinal sand dunes indicating a dominant wind direction perpendicular to the coast. The sand is transported from the Nile delta by Eastern Mediterranean currents eastwards and northwards along the coast of Sinai and Israel. The sand is migrating inland forming di!erent types of dunes. The mineral spectra of the aeolianites are dominated by quartz and some minor feldspar (Goldsmith and Golik, 1980). 夽
Paper published in December, 2000. * Corresponding author. Tel.: 01242-54-4091; fax: 01242-532-997. E-mail address: [email protected] (M. Frechen).
Owing to the complexity of the numerous exposures of kurkar and hamra deposits in the elongated ridges along the coastal plain, it is di$cult to set up a reliable stratigraphy. Ronen (1975) distinguished eight palaeosols, which are intercalated into the kurkar deposits of the Coastal Plain. Five palaeosols furnish artifacts covering the Lower Palaeolithic to the Mesolithic and indicating a cyclical change in periods of aridity and phases of habitation (higher precipitation). Gvirtzman et al. (1984) correlated the kurkar and hamra formation with high and low sea level, respectively, whereas Brunnacker et al. (1982) and Boenigk et al. (1985) correlate the hamra formations with high sea level. Yaalon (1967) questioned the simple correlation of kurkar and hamra sequences with the cold and warm cycles of the marine record on the basis of the oxygen isotope stages. Gvirtzman et al. (1998) no longer correlate between high sea stands and the formation of kurkars. The intensity of soil formation depends on the availability of rain water. Periods with high precipitation result in the complete dissolution of carbonates and the formation of hamras, which are carbonate-free (Yaalon and Dan, 1967). Periods of moderate precipitation result in a part solution of carbonate, as evidenced by carbonate nodules in the soil (Wieder and Yaalon, 1974), hence
0277-3791/01/$ - see front matter 2000 Elsevier Science Ltd. All rights reserved. PII: S 0 2 7 7 - 3 7 9 1 ( 0 0 ) 0 0 0 3 6 - 6
806
M. Frechen et al. / Quaternary Science Reviews 20 (2001) 805}809
in the stabilization of sand dunes and the formation of a thin crust of sandy regosol (`cafeH -au-laita soil type), e.g. at the top of the Nahsholim sands and two regosols intercalated within the Ta'arukha sands. The climatic and environmental e!ect of the availability of bioclastic sediments in the littoral zone is still unclear. It is likely that the bioclastic material was available in the littoral zone during the formation of the Ramat Gan, Dor and Tel Aviv kurkars (Gvirtzman et al., 1998). The Nahsholim, Ta'arukha and Hadera sands were not cemented because bioclastic material was not available in the littoral zone or within the aeolianites. In the Carmel Coast, the only periods of high precipitation are linked with the Middle Palaeolithic soil and the Epi-Palaeolithic soil (Ronen, 1975). The section at Givat Olga, probably a former outlet of Nahal Hadera, is situated at the coastal cli! of the northern end of the Sharon Coastal Plain and close to the southern end of the Carmel Plain (Fig. 1). The more than 17 m thick sequence is composed of four lithological units: kurkar, hamra complex, carbonaceous sandstone (`plataa) and loose sand dunes from the bottom to the top (Fig. 2). The section at Givat Olga has not yielded #int artifacts, but a small distance inland a few wellpreserved, in situ Epi-Palaeolithic sites embedded in red loam clearly indicate an late-Pleistocene age of this loam (Ronen et al., 1975, Hefziba; Ronen and Kaufman, 1976, Hadera I and II; Gopher, pers. comm., Hadera V.). In order to get a more reliable chronological framework, sixteen samples were taken from the section at Givat Olga and investigated by luminescence dating, resulting in 31 infrared optically stimulated luminescence (IRSL) and thermoluminescence (TL) age estimates. This study is a part of a high-resolution systematic luminescence dating study carried out on kurkar and hamra deposits in a north}south transect of the coastal plain between Netanya and Haifa (see also Engelmann et al., 2001).
2. Methodology
Fig. 1. Map showing kurkar ridges between Netanya and Haifa and the location of the section at Givat Olga, Israel.
The samples were taken as 3}5 kg specimens or in light-tight cylinders in the "eld. The outer light-exposed part of the specimen was removed under subdued light in the laboratory and used for gamma spectrometry. The aeolianites were prepared for luminescence analysis by removing the carbonate in 17% hydrochloric acid, by sieving to separate the 100}200 lm grain-size fraction, followed by treatment with 0.01 n sodium oxalate and 30% hydrogen peroxide to remove clay coatings and organic matter, respectively. The remaining material was sieved again to separate the 100}125 lm grain-size fraction. Potassium feldspar and quartz minerals were extracted from all samples by heavy liquid separation with sodium
M. Frechen et al. / Quaternary Science Reviews 20 (2001) 805}809
807
a TL/OSL Ris+ reader (TL-DA-15) at the Cheltenham Geochronology Laboratories. A "lter combination of Schott BG-39 and Corning 7-59 was placed between the photomultiplier and the aliquots, for both IRSL and TL measurements. After 25 s of IR exposure (880$80 nm), the same discs were heated immediately to obtain their TL at a heating rate of 53C/s up to 4503C. Second glow normalization was applied in order to reduce the discto-disc scatter for both IRSL and TL. Equivalent doses were obtained by integrating the 10}25 s region of the IR decay curve and the 300}4003C region of the TL glow curve for the additive dose method. An exponential growth curve was "tted for the di!erent dose steps and the natural luminescence signal and extrapolated to zero, to estimate the equivalent dose using the software developed by Rainer GruK n, Canberra. Dose rates for all samples were obtained from potassium, uranium and thorium contents, measured by gamma spectrometry in the laboratory, assuming a water content of 5$2.5% for the kurkar and carbonaceous sandstone and 9$3% for the hamra. A radioactive equilibrium was assumed as well. The potassium content of the alkali feldspars was determined by thick source beta counting, ranging from 3.2$0.3 to 7.1$0.7%. However, the alkali feldspar separation was rather poor, owing to a contamination with quartz, hence a value of 12.5$2% was taken for the potassium content in feldspar for each sample, as suggested by Huntley and Barril (1997). A correction was calculated for the attenuation of the cosmic dose rate with depth (cf. Aitken, 1985). Fading experiments have not indicated any signi"cant fading under the present technique.
3. Results
Fig. 2. Lithological sequence and position of the samples, geological description and IRSL and TL age estimates for the section at Givat Olga.
polytungstate (2.58, 2.62 and 2.70 g/cm). The potassium feldspar grains were "xed on aluminium discs and successively irradiated in at least six di!erent dose steps by a Co-60 gamma source with a dose rate of 7.8 and 8.0 Gy min\ depending on the sample position. Two weeks after irradiation and storing at room temperature, the samples were preheated on a heating plate at 1603C for 16 h, followed by more than 6 weeks, storage at room temperature. The samples were measured using
Dosimetric results are listed in Table 1, as determined by gamma spectrometry. A radioactive disequilibrium within the U-238 decay chain, caused by radon loss, was not detectable by gamma spectrometry measuring and comparing the Ra-226 and Pb-215 energy peaks. The mean total dose rate is 1.08 Gy/ka ranging from 0.90 to 1.30 Gy/ka for the kurkar, carbonaceous sandstone and loose aeolian sands. The mean dose rate of the samples from the hamra is 1.35 Gy/ka ranging from 1.07 to 1.60 Gy/ka. The equivalent dose values increase with depth from 3.4$0.4 to 128.5$24.4 Gy and from 3.0$0.5 to 103.3$5.1 Gy for IRSL and TL, respectively, indicating four main data clusters (Table 1). The luminescence age estimates are discussed with respect to the four lithological units from the bottom to the top: (a) Kurkar, (b) Hamra complex, including Epi-Palaeolithic soil,
66.5$5.8 74.5$6.4 52.9$4.8 61.5$7.4 52.2$5.1
3.3$0.5 4.8$0.5 5.3$0.7 4.1$0.3 5.6$0.7 5.7$0.8 12.3$1.4 14.2$1.6 19.4$2.0 33.0$2.8 41.9$8.2 50.5$9.0 55.7$5.0 54.7$9.1 100.6$20.5 66.9$7.0 98.7$5.0 103.3$5.1 53.2$1.9 78.5$7.4 68.0$4.4
3.0$0.5 3.6$0.3 3.4$0.3 11.1$1.0 4.1$0.7 6.2$0.4 13.3$1.3 23.0$5.6 24.7$2.2 47.9$1.0
3.4$0.4 4.6$0.3 4.8$0.5 4.7$0.2 6.1$0.6 5.8$0.6 14.6$1.2 16.1$1.3 20.8$1.4 53.0$2.9 65.5$12.1 74.9$12.3 77.2$4.3 55.0$8.0 128.5$24.4 87.1$6.6
1.04$0.08 0.95$0.08 0.90$0.08 1.15$0.08 1.08$0.08 1.02$0.08 1.18$0.09 1.13$0.09 1.07$0.09 1.60$0.11 1.57$0.11 1.48$0.10 1.39$0.10 1.01$0.08 1.28$0.09 1.30$0.10
IRSL (ADD) age (ka) Dose rate (Gy/ka) ED TL (ADD) (Gy) ED IRSL (ADD) (Gy)
150.0$5 150.0$5 126.0$5 106.5$5 64.5$5 64.5$5 33.0$5 33.0$5 33.0$5 33.0$5 33.0$5 13.5$5 13.5$5 13.5$5 13.5$5 13.5$5 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 12.5$2 0.3$0.02 0.3$0.02 0.3$0.02 0.3$0.02 0.2$0.02 0.4$0.03 0.5$0.04 0.5$0.04 0.5$0.03 0.8$0.06 0.8$0.06 0.8$0.06 0.7$0.05 0.4$0.03 0.7$0.05 0.7$0.05 0.4$0.03 0.4$0.03 0.4$0.03 0.4$0.03 0.4$0.03 0.4$0.02 0.5$0.04 0.5$0.04 0.5$0.03 0.9$0.06 0.8$0.05 0.7$0.05 0.6$0.04 0.6$0.04 0.6$0.04 0.6$0.04 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG OLG
1.3$0.09 0.9$0.06 0.9$0.06 3.9$0.3 4.2$0.3 1.2$0.08 2.2$0.2 2.0$0.1 1.7$0.1 3.8$0.3 3.3$0.2 2.9$0.2 2.4$0.2 0.8$0.05 1.0$0.07 1.0$0.07
Cosmic radiation dose Internal potassium (%) Potassium (%) Uranium (ppm)
Thorium (ppm)
(c) Carbonaceous sandstone (`plataa), (d) Loose aeolian sands. The kurkar deposits are the oldest unit at the section at Givat Olga. IRSL and TL age estimates range from 66.9$7.0 to 54.7$9.1 and from 61.5$7.4 to 52.2$5.1 ka, respectively (Fig. 2). The IRSL age estimate of OLG2 was not taken into account owing to signi"cant disc-todisc scatter. The lower part of the hamra yielded a similar IRSL age results ranging from 55.7$5.0 to 50.5$9.0 ka. It is likely that the palaeosol superimposed the upper part of the kurkar. Five samples were taken from the upper part of the hamra complex. The IRSL and TL age estimates range from 41.9$8.2 to 11.2$1.4 ka. The loose sand on top of the hamra yielded luminescence age estimates ranging from 6.1$0.6 to 5.7$0.8 ka. The loose sand is covered by well-cemented calcareous sandstone (`plataa). The IRSL age estimates are slightly younger than those of the underlying loose sand ranging from 5.6$0.7 to 4.1$0.3 ka. The youngest sediments, the uppermost loose aeolian sand, yielded IRSL and TL age estimates ranging from 5.3$0.7 to 3.3$0.5 and from 3.8$0.5 to 2.9$0.5 ka, respectively.
4. Discussion and conclusion
Sample
Table 1 Dosimetric and chronological results for section Givat Olga
2.9$0.5 3.8$0.5 3.8$0.5 9.7$1.1 3.8$0.7 6.1$0.6 11.2$1.4 20.3$5.2 23.0$2.7 29.9$2.1
M. Frechen et al. / Quaternary Science Reviews 20 (2001) 805}809 TL (ADD) age (ka)
808
The stratigraphically oldest sediment at section Givat Olga is designated to represent stratigraphically the Ramat Gan kurkar, Nahsholim sand and Dor kurkar (Gvirtzman et al., 1998), which are likely to be an equivalent of kurkar II, see Boenigk et al. (1985). Luminescence dating in the area yielded IRSL age estimates between 64$8 and 48$4 ka for Ramat Gan kurkar, Nahsholim sand and Dor kurkar (Porat and Wintle, 1994), which are in excellent agreement with the IRSL and TL results of this study. The lower part of the hamra at section Givat Olga yielded IRSL age estimates of 55.7$5.0 and 50.5$9.0 ka, which are in agreement with 51$3 and 56$5 ka for the Netanya hamra in the Sharon coast determined by Porat and Wintle (1994) and Ritte et al. (1997). At section Givat Olga, no Middle Palaeolithic artifacts have been found from the lower part of the hamra. The upper brown clayey palaeosol is designated to represent the Epi-Palaeolithic soil. The IRSL age estimates range from 19.4$2.0 to 12.3$1.4 ka for the upper part of this hamra complex, which is in agreement with the time period of Epi-Palaeolithic industries between 20 and 10 ka. The calcareous sandstone (`plataa) is likely to be an equivalent of the Tel Aviv kurkar, which is assumed by the luminescence age estimates ranging from 5.6$0.7 to 4.1$0.3 ka. The "rst IRSL and TL study in the area between Netanya in the south and Haifa in the north yielded
M. Frechen et al. / Quaternary Science Reviews 20 (2001) 805}809
excellent agreement between the luminescence studies on single and multiple aliquot by Porat and Wintle (1994) and Ritte et al. (1997) further south. The following stratigraphic correlation seems to be most likely. Kurkar II (Boenigk et al., 1985) is designated to be an equivalent of the Ramat Gan kurkar (Gvirtzman et al., 1998). At present, it is still unclear whether the Nahsholim sands and the Dor kurkar coincide with kurkar II as well. The Netanya hamra (Gvirtzman et al., 1998) is likely an equivalent of the Epi-Palaeolithic soil (Ronen, 1983). The Tel Aviv kurkar is likely to be an equivalent of the carbonaceous sandstone (`plataa) and kurkar III, assumed by the chronological results. The latter sediments and the loose aeolian sands on top of the section are of Holocene deposition age at the section at Givat Olga. A comparison with the marine oxygen isotope record seems to be too speculative at the present stage. It is likely, that the shoreline kurkar ridge along the Sharon coast formed during an older period of the last glaciation, probably before 50 ka BP. Furthermore, it is probable that the kurkar ridges of the Carmel coast formed synchronously within short periods of maximum 10}15 ka, most likely during 65 and 50 ka BP. At section Givat Olga, the hamra formation, including part of the Middle Palaeolithic and the Epi-Palaeolithic, took place between 60 and 10 ka, whereas dune sand formation (Tel Aviv kurkar, Ta'arukha and Hadera sands) was active during part of the Holocene. Acknowledgements The authors thank the German}Israeli Foundation for funding [Project-No. I132-301.02/95] and Cathryn Sharp, Cheltenham, for drafting Figs. 1 and 2, Frank Chambers and Naomi Porat for improvement of an earlier version of the manuscript. Thanks to ReneH R. Debuyst for his support for Irradiation which was carried out at INAN, UniversiteH catholiques de Louvainla-Neuve, Belgium. References Aitken, M.J., 1985. Thermoluminescence Dating. Academic Press, London. 359 pp.
809
Boenigk, W., Brunnacker, K., Tillmanns, W., Ronen, A., 1985. Die AG olianite in der noK rdlichen KuK stenebene von Israel * Genese. Stratigraphie und Klimageschichte. QuartaK r 35/36, 113}140. Brunnacker, K., Ronen, A., Tillmanns, W., 1982. Die jungpleistozaK nen AG olianite in der suK dlichen KuK stenzone von Israel. Ein Beitrag zur zeitlich-raK umlichen Klimaentwicklung. Eiszeitalter und Gegenwart 32, 23}48. Engelmann, A., Neber, A., Frechen, M., Boenigk, W., Ronen, A., 2001. Luminescence chronology of Upper Pleistocene and Holocene aeolianites from Netanya South * Sharon Coastal Plain, Israel. Quaternary Science Reviews (Quaternary Geochronology) 20, 799}804. Goldsmith, V., Golik, A., 1980. Sediment transport model of the southeastern Mediterranean coast. Marine Geology 37, 147}175. Gvirtzman, G., Netser, M., Katsav, E., 1998. Last-Glacial to Holocene kurkar ridges, hamra soils and dune "elds in the coastal belt of Israel. Israelian Journal of Earth Science 47, 29}46. Gvirtzman, G., Shachnai, E., Bakler, N., Ilani, S., 1984. Stratigraphy of the kurkar group (Quaternary) of the coastal plain of Israel. Geological Survey Israel, Current Research 1983}84, 70}82. Huntley, D.J., Barril, M.R., 1997. The K content of the K-feldspars being measured in optical dating or in thermoluminescence dating. Ancient TL 15, 11}13. Porat, N., Wintle, A.G., 1994. IRSL dating of kurkar and hamra from the Givat Olga Member in the Sharon Coastal Cli!, Israel. Israel Geological Society, Proceedings of the Annual Meeting, 1994, p. 85. Ritte, M., Porat, N., Gvirtzman, G., 1997. Stratigraphy of the coastal cli! of the Sharon environments of deposition and luminescence dating. Israel Geological Society, Proceedings of the Annual Meeting 1997, pp. 92}93. Ronen, A., 1975. The Palaeolithic archaeology and chronology of Israel. In: Wendorf, F., Marks, A.E. (Eds.), Problems in Prehistory: North Africa and the Levant, Dallas, pp. 229}248. Ronen, A., 1983. Late Quaternary sea levels inferred from coastal stratigraphy and archaeology in Israel. In: Masters, P.M., Flemming, N.C. (Eds.) Quaternary Coastlines and Marine Archaeology Towards the Prehistory of Land Bridges and Continental Shelves. London, pp. 293}304. Ronen, A., Kaufman, D., 1976. Epi-palaeolithic sites near Nahal Hadera. Central Coastal Plain of Israel. Tel Aviv 3, 16}30. Ronen, A., Kaufman, D., Gophna, R., Bakler, N., Smith, P., Amiel, A., 1975. The Epi-Palaeolithic site Hefziba. Central Coastal Plain of Israel. QuartaK r 26, 53}74. Wieder, M., Yaalon, D.H., 1974. E!ect of matrix composition on carbonate nodule crystallisation. Geoderma 11, 95}121. Yaalon, D.H., 1967. Factors a!ecting the lithi"cation of eolianite and interpretation of its environmental signi"cance in the coastal plain of Israel. Journal of Sedimentology and Petrology 37, 1189}1199. Yaalon, D.H., Dan, J., 1967. Factors controlling soil formation and distribution in the Mediterranean coastal plain of Israel during the Quaternary. Quaternary Soils, 7th INQUA Congress, 1965, pp. 321}338.