- Email: [email protected]
Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS Annales de Paléontologie xxx (2019) xxx–xxx
Disponible en ligne sur
ScienceDirect www.sciencedirect.com
Original article
Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand Stratigraphie et paléontologie des séquences du Carbonifère Moyen de Phu Bo Bit dans la province de Loei en Thaïlande Sathaporn Kavinate a,b,∗ , Mongkol Udchachon a,c , Henri Fontaine d a
Department of Biology, Faculty of Science, Mahasarakham University, 44150 Maha Sarakham, Thailand Department of Mineral Resources, 75/10 Rama VI, Rachathavi, 10400 Bangkok, Thailand c Palaeontological Research and Education Centre, Mahasarakham University, 44150 Maha Sarakham, Thailand d 128, rue du Bac, 75007 Paris, France b
a r t i c l e
i n f o
Article history: Received 30 November 2018 Accepted 12 July 2019 Available online xxx Keywords: Middle Carboniferous Palaeontology Stratigraphy Fusulinaceans Loei
a b s t r a c t The rocks from the Phu Bo Bit section consist of shale and limestone along with an abundant and diverse invertebrate fauna consisting of brachiopods, corals, bryozoans and crinoids, interpreted as having been deposited in shallow marine or shelf environments. At Phu Bo Bit, thick limestone lenses in shale contain microfossils. Based on the foraminiferan and algae assemblage, the stratigraphic sequence of Phu Bo Bit extends from the late Bashkirian to the early Moscovian. According to lithofacies and palaeontology, the Phu Bo Bit section represents the change from carbonate to siliciclastic sedimentation, which provides new evidence on the marine regression during the mid-Carboniferous. © 2019 Elsevier Masson SAS. All rights reserved.
r é s u m é Mots clés : Carbonifère moyen Paléontologie Stratigraphie Fusulines Loei
La séquence stratigraphique à Phu Bo Bit correspond à des schistes argileux et des calcaires renfermant une riche faune d’invertébrés, dont des brachiopodes, des coraux, des bryozoaires et des crinoïdes. En termes d’environnements de dépôt, ces sédiments se sont déposé dans un environnement marin de plateforme peu profond. Les lentilles calcaires contenues dans les schistes argileux renferment des microfossiles. Sur la base de la composition en foraminières et en algues fossiles, la séquence stratigraphique de Phu Bo Bit s’étend du Bashkirien supérieur au Moscovien inférieur. Les micro-lithofaciès et les assemblages paléontologiques montrent que la séquence passe d’une sédimentation carbonatée à silico-clastique, ce qui corresponds à l’hypothèse d’une régression marine durant le Carbonifère moyen. ´ ´ es. © 2019 Elsevier Masson SAS. Tous droits reserv
1. Introduction Carboniferous sedimentary rocks are widely exposed in several areas of Thailand and were deposited in widely diverse environments (Ueno and Charoentitirat, 2011; Fontaine et al., 1991, 2005). The Loei area is one of the key areas in Thailand with a good expo-
∗ Corresponding author. Department of Biology, Faculty Mahasarakham University, 44150 Maha Sarakham, Thailand. E-mail address: [email protected] (S. Kavinate).
of
Science,
sure of Carboniferous rock succession, but few reports on detailed stratigraphy and palaeontology have been published so far. They contain marine microfossils (foraminiferans and algae) and frequently corals, which are common in the Indochina Block. The Phu Bo Bit sequence, Muang District, in Loei Province studied in the present paper was previously reported by Fontaine and co-authors in 2005, it contains diverse fossils, including corals (Fontaine et al., 1990, 1991), algae and foraminiferans corresponding to the late Bashkirian to early Moscovian (Fontaine et al., 2005). The purpose of this study is to investigate the geology, sedimentology, stratigraphy and palaeontology in order to interpret the depositional
https://doi.org/10.1016/j.annpal.2019.08.001 0753-3969/© 2019 Elsevier Masson SAS. All rights reserved.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
2
Fig. 1. Topographic map of the Phu Bo Bit located east of Muang district, Loei Province. Sampling locations are indicated with solid circles. Carte topographique de Phu Bo Bit à l’Est du district de Muang dans la province Loei. La localisation des échantillonnages est représentée par des cercles pleins.
environment of the ‘middle’ Carboniferous in the Loei area. Most materials studied herein have been collected by Fontaine (localities 1 to 7 (Fontaine et al., 2005)), with one additional locality (locality 8) and the thin sections from these localities are studied for the first time (Fig. 1). Materials in this study are deposited in the Palaeontological Research and Education Centre, Mahasarakham University, Thailand. 2. Geological setting The Phu Bo Bit section was mapped in one measured section oriented approximately in an east-west direction as shown in Fig. 1. The total length of section was about 5 km. Rock samples were collected for detailed petrographic study. The representative sedimentary sequence of the section at Phu Bo Bit is shown in Fig. 2. Two rock units may be identified from the fieldwork and the description of each unit is presented in ascending order as follows: A hill 2 km east of Loei consists of thick limestone lenses in shale containing foraminiferans, Tabulata and solitary Rugosa. They have
been assigned to the Upper Bashkirian (Fontaine et al., 1991, 1995, 2005). Along the northern base of Phu Pho Bit, a section of shale, calcareous mudstone, argillaceous limestone, limestone and sandstone is well exposed along the road from Ban Na Bon (5 km south of Pha Tha) to Ban Phia. It is rich in fossils at many levels: foraminiferans, solitary Rugosa with and without dissepiments, Chaetetes, bryozoans, brachiopods and gastropods (Fig. 3). Beds dip towards the east. Samples have been collected from west to east. Fossils have been collected at six localities among eight investigated (Fig. 4). At the eighth locality (Fig. 1; 792551E, 1937839N; samples LST015 to LST017), 2 km east of Ban Na Bon, in a small limestone quarry, small lenses of black limestone occur in the shale. Limestone is packstone, again very rich in tubular algae and fusulinaceans. At the first locality (Fig. 1; 793900E, 1937300N; samples T7795 to T7797), argillaceous limestone and calcareous mudstone contain diverse fossils: dissepimented solitary corals, bryozoans,
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
3
Fig. 2. Lithostratigraphic column of Phu Bo Bit showing intercalation of late Bashkirian through Moscovian shale and limestone. The main stratigraphic column is based on Charoenprawat and Wongwanich, 1976. Colonne stratigraphique à Phu Bo Bit montrant la séquence carbonatée et argileuse du Bashkirien au Moscovien. La colonne stratigraphique est basée sur les travaux de Charoenprawat et Wongwanich, 1976.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9 4
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
Fig. 3. A. Field photographs showing view from south of Phu Bo Bit. B. Contact of siliceous shale and very thick-bedded limestone in the middle part of the Phu Bo Bit section. C. A quarry near the foothill of Phu Bo Bit showing exposure of limestone. D. A colony of tabulate coral. E. Massive rugose coral and F. Solitary coral at Phu Bo Bit section. A. Photographie de terrain dans la partie Sud de Phu Bo Bit. B. Contact entre schistes argileux siliceux et épais banc calcaire dans le milieu de la section de Phu Bo Bit section. C. Carrière à la base de la coline de Phu Bo Phit montrant des affleurements calcaires. D. Colonie de corail tabulé. E. Corail rugueux massif F. Corail solitaire de la section de Phu Bo Bit.
brachiopods and gastropods. Fragments of algae and fusulinaceans are rare and poorly preserved. At the second locality (Fig. 1; 794300E, 1937500N; samples T7641 to T7650), a dark grey limestone is associated with shale and sandstone. It is locally very rich in fossils. Algae (Beresella erecta Maslov & Kulik, 1956) are commonly in great abundance similar to those of the Moscovian limestone exposed in a pond at Ban Na Duang about 15 kilometers east of Loei (Fontaine and Suteethorn, 2000). Other fossils are rare and include smaller foraminifera (Nodosariidae), fusulinaceans, dissepimented solitary corals and crinoids. At the third locality (Fig. 1; 794200E, 1937500N; samples T7798 to T7801), 2.3 km east of Ban Na Bon, limestone beds in shale contain very rare dissepimented solitary corals. Algae are still in abundance but fusulinaceans are very rare. At the fourth locality (Fig. 1; 794800E, 1937700N; sample T7802), shale without fossils is present. At the fifth locality (Fig. 1; 796300E, 1937400N; samples T7803 to T7805), 3.5 km east of Ban Na Bon, small lenses of black limestone
occur within the shale. Limestone is packstone, again very rich in tubular algae and with rare fusulinaceans (T7805). At the sixth locality (Fig. 1; 797100E, 1936300N; sample T7806), shale with sandstone intercalations is present. At the seventh locality (Fig. 1; 797900E, 1936100N; samples T7807 to T7812), small limestone (wackestone to packstone) lenses in shale contain calcispheres, smaller foraminifera (Globivalvulina), scattered and poorly preserved fusulinaceans (Profusulinella sp.), Chaetetes, Multithecopora and solitary corals with and without dissepiments. The shale is locally rich in brachiopods. The solitary corals with dissepiments belong to Caninophyllum. They are about 3 cm in diameter, with 40 to 44 major septa and extremely short minor septa. Dissepiments are arranged in about 8 rows. Other solitary corals are small, 5 to 6 mm in diameter. They display a columella and probably belong to Amygdalophylloides. Chaetetes consists of two species: a species with corallites 0.6 mm in diameter, the other species with corallites 0.4 mm in diameter. The corallites of Multithecopora are 1.5 mm in diameter.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
5
Fig. 4. A and B. A rock slab and photomicrograph of sample no. LST18 showing fusulinid and bioclastic fragments. C and D. A rock slab and photomicrograph of sample no. LST021 showing algal and bioclastic fragments dispersed in micrite matrix of microfacies. E and F. A rock slab and photomicrograph of sample no. LST015 showing fusulinid and bioclastic fragments from Phu Bo Bit section. Scale bar = 1 mm. A et B. Section de roche et microphotographie de l’échantillon no LST18 montrant des Fusulinidae et des bioclastes. C et D. Section de roche et microphotographie de l’échantillon LST021 montrant des algues et des bioclastes dans une matrice micritique. E et F. Section de roche et microphotographie de l’échantillon LST015 montrant des fusulinidés et des bioclastes de la séquence de Phu Bo Bit. Barre d’échelle = 1 mm.
Taxa of major fossil groups observed in the Phu Bo Bit Section are summarized in Table 1. 3. Systematic Palaeontology 3.1. Foraminifera Phylum PROTOZOA Class SARCODINA Order FORAMINIFERIDA Eichwald, 1830 Suborder FUSULININA Wedekind, 1937 Superfamily FUSULINACEA Moller, 1878 Family PSUDOSTAFFELLIDAE Putria, 1956 Subfamily FUSULINELLINAE Staff and Wedekind, 1910 Genus Profusulinella Rauser and Beliaev, 1936 Profusulinella sp. (Figs. 5A–G and 6A–C)
Description. Shell minute, inflated fusiform to subellipsoidal, with bluntly rounded poles. Mature specimens possess 4–6 volutions and measure from 0.9 to 1.25 mm in length and from 0.5 to 1 mm in diameter. Tunnel rather narrow, about half as high as chambers. Chomata massive and wide. Age/Remarks. Carboniferous, late Bashkirian to early Moscovian. Occurrence: Phu Bo Bit, Samples LST015 to LST017. Profusulinella rhombiformis; is reported in the valley of the Nam Huai, 3 km east of Ban Tat So area, northeast of Loei (Fontaine, 1990) and Ban Tha Sot, 38 km north-northeast of Loei (Fontaine et al., 1982). The genus Profusulinella is reported worldwide; in Russia (upper Bashkirian to lower Moscovian; Geology of Russia, 1963), in Anarak Section of Central Iran (late Bashkirian–early Moscovian; Fassihi et al., 2017), southern and northern Urals (Moscovian; Dzhenchuraeva and Okuyucu, 2007) and southern Turkey (early Moscovian; Kobayashi, 2011) which indicates a tropical shallow marine platform during the mid-Carboniferous.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
6
Table 1 Taxa of major fossil groups observed in the Phu Bo Bit Section. Taxons des principaux groupes fossiles observés dans la section de Phu Bo Bit. Age Pennsylvanian Carboniferous Moscovian
Fossils
Algae Foraminifer Small foraminifera
Corals
Bashkirian
Algae Foraminifera
Small foraminifera
Corals Other fossils
Beresella sp. Profusulinella sp. Bradyina sp. Climacammina sp. Endothyra sp. Caninophyllum sp. Caninia sp. Multithecopora Beresella sp. Profusulinella sp. Eostaffella sp. Ozawainella sp. Climacammina sp. Globivalvulina sp. Bradyina sp. Endothyra sp. Chaetetes sp. Multithecopora sp. Brachiopods Bryozoans Gastropods Ostracods Crinoids Trilobites
Family OZAWAINELLIDAE Thompson & Foster, 1937 Genus Ozawainella Thompson, 1935 Ozawainella sp. (Fig. 6D) Description. Shell umbilicate to spherical or elongate, evolute in early forms, involute or irregularly uncoiled in later ones, axis of coiling short or long, first few volutions discoidal, others spherical to unevenly elongate; spirotheca composed of tectum with upper and lower tectoria in early forms but diaphanotheca occurring below tectum and above lower tectorium in later ones; septa plane; shell generally planispiral but may be asymmetrical, discoidal in at least part of shell with coiling axis in shortest diameter; tunnel singular. Age/Remarks. Late Mississippian–‘late’ Permian (Lopingian). Occurrence. Phu Bo Bit, Samples LST016 and LST018. This genus suggests a latest Bashkirian–earliest Moscovian age comparable to the Melekessian–Vereian transition in the Russian Platform (Fassihi et al., 2017). Ozawainella pararhomboidalis was reported from the Bashkirian Stage (Dzhenchuraeva and Okuyucu, 2007). Ozawainella occurs in Central Asia in the late Bashkirian–early Moscovian. Superfamily ENDOTHYRACEA Brady, 1884 Family ENDOTHYRIDEA Brady, 1884 Subfamily ENDOTHYRINAE Brady, 1884 Genus Endothyra Phillips, 1846 Endothyra sp. (Fig. 5G, from the Phu Bo Bit section) Description. Test enrolled, partially involute, plane of coiling changes during growth, turning through 30–90◦ , may turn gradually as in plectogyral coiling, or abruptly nearly 90◦ , few chambers to whorl, whorls few; wall calcareous, with 2 layers, thin dark outer layer (tectum) and thicker, fibrous alveolar, inner layer
(diaphanotheca); partial recrystallization may result in a granular appearance, secondary deposits in form of nodes, ridges, or forward directed hooks secreted on chamber floors; external aperture not always evident, but an interiomarginal, equatorial to asymmetrical slit may be present, relatively large intercameral foramina in same position. Late Devonian (Famennian), Early Age/Remarks. Carboniferous–Permian. Occurrence. Phu Bo Bit, Sample LST016. This genus has been reported worldwide such as Endothyra bradyi from central Urals (Bashkirian–Moscovian; Perm State University, 2015), Endothyra ex gr. bowmani (Serpukhovian) from southern Urals and Endothyra rzhevica from Russia (Serpukhovian and Serpukhovian-lower Bashkirian; Davydov, 2008) Family BISERIAMMINIDAE Chernysheva, 1941 Genus Globivalvulina Schubert, 1921 Globivalvulina sp. (Fig. 5F) Description. Test biserial, involute; aperture at inner border of septal face. Age/Remarks. Early Carboniferous (Mississippian)–Permian. Occurrence. Phu Bo Bit, Sample LST016. This genus is found worldwide. It was reported from the central Urals (Bashkirian–Moscovian; Perm State University, 2015). Bozorgnia (1973) attributed the smaller foraminiferans occurring in sediments of the Dozdehband formation in Iran to this genus, suggesting that the upper part of the sequence in question is probably of early Bashkirian age (Leven and Gorgij, 2011). In China, the genus was reported from the Early Carboniferous–Permian (Vachard et al., 2006). 3.2. Algae Order BERESELLALES Maslov and Kulik, 1956nomen translat. herein Family BERESELLACEAE Maslov and Kulik, 1956 nomen translat. H. Termier et al., 1977 see also G. Termier et al., 1977, p. 141 (ex tribe)orth mut. Shuysky, 1985 (ex Beresellidae) (non Deloffre, 1987, nec Shuysky, 1987, nec Deloffre, 1988) Tribe Bereselleae Maslov and Kulik, 1956 Genus Beresella Makhaev, 1937 ex Maslov and Kulik, 1956 Beresella sp. (Figs.5C and 6E) Description. Cylindrical microproblematic algae, undivided but with internal diaphragms more or less numerous. The tubular undivided skeletons are occasionally bifurcated, and have an outer smooth or finely costulate surface, and an internal cavity. In between, the re-entrants, darker rings, are finely canaliculate. The canalicules are blind, because they are overlain by a continuous external layer (Vachard, 1991, 2009). Age/Remarks. Late Carboniferous (Pennsylvanian) Occurrence. Phu Bo Bit, Samples LST015 and T7589. This genus is reported worldwide; such as from the Kuzuoluk section of Southern Turkey (Bashkirian–Moscovian), including Beresella erecta Maslov and Kulik, 1956 and Beresella ishimica Kulik, 1964 (Dzhenchuraeva and Okuyucu, 2007). It has been recorded in Spain from the upper part of the Picos de Europa Formation at Las Llacerias section, in the late Moscovian beds (Myachkovian) (Mamet and Villa, 2004) and in the central Urals (Bashkirian–Moscovian; Kossovaya, 2015), which indicates shallow-marine palaeoenvironments (Wray, 1977; Krainer et al., 2003). Beresella sp. is also
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
7
Fig. 5. Fusulinids from the Phu Bo Bit Section (late Bashkirian to early Moscovian). A. Profusulinella sp. (Sample LST015). B. Profusulinella sp. (Sample LST015). C. Beresella erecta and Profusulinella sp. (Sample LST015). D. Profusulinella sp. (Sample LST016). E. Profusulinella sp. (Sample LST015). F. Profusulinella sp. and Globivalvulina sp. (Sample LST016). G. Profusulinella sp. and Endothyra sp. (Sample LST016). Scale bar = 1 mm. Fusulinidés de la séquence de Phu Bo Bit (late Bashkirian to early Moscovian). A. Profusulinella sp. (échantillon LST015). B. Profusulinella sp. (échantillon LST015). C. Beresella erecta et Profusulinella sp. (échantillon LST015). D. Profusulinella sp. (échantillon LST016). E. Profusulinella sp. (échantillon LST015). F. Profusulinella sp. et Globivalvulina sp. (échantillon LST016). G. Profusulinella sp. et Endothyra sp. (échantillon LST016). Barre d’échelle = 1 mm.
reported from a Pennsylvanian algal reef in south Guizhou, China (Gong et al., 2007), a Moscovian algal mound from Tarim, NW China (Chen, 2012) and Pennsylvanian algal buildups of the Carnic Alps, Austria (Samankassou, 2003). 4. Brief description of the microfacies of limestone Lithology investigation and observations are combined with microfacies studies. It consists of the description and interpretation of the sedimentary facies as well as the occurrence and composition of the biota. This information is the basis for reconstruction of the depositional settings.
Carbonate textures and allochemical constituents are observed in thin sections under a petrographic microscope. The facies types are defined on the basis of lithology, allochemical constituents, texture, and fossil associations in order to reconstruct their depositional environment. Carbonate rock classification developed either by Folk (1959, 1962) or Dunham (1962) and also Embry and Klovan (1971) were applied for limestone classification in this study. As a result, five microfacies types are recognized for limestones from the Phu Bo Bit section including Microfacies I, algal lamination; Microfacies, II pelmicrite; Microfacies III, sparse biomicrite; Microfacies IV, packed biomicrite and Microfacies V, biosparite. The lithological characteristics and depositional environments of these microfacies are summarized in Table 2.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
8
Fig. 6. Fusulinids and algae from the Phu Bo Bit section (late Bashkirian to early Moscovian). A. Profusulinella sp. (Sample LST017). B. Profusulinella sp. (Sample LST016). C. Profusulinella sp. (Sample LST018). D. Ozawainella sp. (centre and centre right, Sample LST018). E. Beresella sp., longitudinal section and transverse section (Sample T7589). Scale bar = 1 mm. Fusulinidés et algues de la séquence de Phu Bo Bit (Bashkirien supérieur à Moscovien inférieur). A. Profusulinella sp. (échantillon LST017). B. Profusulinella sp. (échantillon LST016). C. Profusulinella sp. (échantillon LST018). D. Ozawainella sp. (au centre et au centre droit, échantillon LST018). E. Beresella sp., sections longitudinale et transverse (échantillon T7589). Barre d’échelle = 1 mm.
Table 2 Summary of the microfacies types identified in the study area and their interpretation in terms of depositional environments. Résumé des types de microfaciès rencontrés dans la section et interprétation en termes d’environnement de dépôt. Microfacies
Lithological characteristics
Depositional environments
I Algal lamination II Pelmicrite III Sparse biomicrite
Very thin-laminae, decayed algae, detrital quartz grains Discrete peloids, fine fossil fragments Poorly sorted, floating grains, micrite matrix
IV Packed biomicrite
In-situ deposition of unfragmented fossils, micrite matrix, fragmentary fossils, intraclasts, carbonaceous matter Intraclasts, fragmented and unfragmented fossils, lumped pellets, poorly to moderately sorted
Shallow subtidal Subtidal zone of inner shelf, low-water energy Subtidal and/or subwave base of a shelf sea close to the shore Subtidal zone below the active wave base
V Biosparite
Intertidal to near shore subtidal above the wave base
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
5. Conclusion The sequence on the northern base of the Phu Bo Bit, in Loei Province, Thailand contains abundant macrofossils (Tabulata (Chaetetes, Multithecopora), solitary Rugosa, bryozoans, brachiopods and gastropods), foraminiferan and algal microfossils. Based on the foraminiferan assemblage, especially fusulinaceans (Profusulinella sp. and Ozawainella sp.), Climacammina sp., Endothyra sp., Globivalvulina sp. and the dasyclad algae Beresella sp., the stratigraphic sequence of Phu Bo Bit extends from the late Bashkirian to the early Moscovian. The carbonate rocks in the study area are divided into five microfacies types based on limestone classification as well as carbonate textures. Excluding crystalline microfacies, packed biomicrite, sparse biomicrite, biosparite, pelmicrite and algal-lamination microfacies are present in decreasing order of abundance, representing the subtidal zone below the active wave base, the subtidal and/or subwave base of the shelf sea close to the shore, the intertidal to near shore subtidal zone above the wave base, the subtidal zone of inner shelf with low-water energy and the shallow subtidal depositional environments respectively. These microfacies represent carbonate facies developed under the influence of low to high energy seas in subtidal to intertidal regimes. Our study on the Phu Bo Bit sequence provides therefore geological evidence on the marine regression in Loei region during the middle Carboniferous (late Bashkirian to early Moscovian). Disclosure of interest The authors declare that they have no competing interest. Acknowledgements The authors would like to express their sincere gratitude to Dr. Varavudh Suteethorn and Mr. Pitaks Ratanajaruraks for their support and encouragement and for providing transportation facilities for our fieldwork. Thanks to two anonymous reviewers who provided helpful comments for good improvements to this manuscript and Dr. Clive Burrett who helped with English. References Bozorgnia, F., 1973. Paleozoic foraminiferal biostratigraphy of central and east Alborz Mountains, Iran. Geological Laboratories Publication 4. National Iranian Oil Company (185 p.). Charoenprawat, A., Wongwanich, T., 1976. Preliminary report on the geology of Changwat Loei (NE47-12), with geological map 1:250 000 scale: Department of Mineral Resources. Bangkok (in Thai). Chen, Z.Q., 2012. A Late Carboniferous algal mound from the Tarim Basin, NW China: internal structure and palaeoecology. Geological Journal 47, 477–494. Davydov, V.I., 2008. Fusulinid biostratigraphic dating of Upper Paleozoic samples from Novaya Zemlya (The Holtedahl collection). In: Arne Nakrem, H. (Ed.), Natural History Museum (Geology), University of Oslo. (27 p.). Dunham, R.J., 1962. Classification of carbonate rocks according to depositional texture. In: Ham, W.E. (Ed.), Classification of Carbonate Rocks. American Association of Petroleum Geologists Memoir 1. , pp. 108–121. Dzhenchuraeva, A.V., Okuyucu, C., 2007. Fusulinid Foraminifera of the Bashkirian–Moscovian boundary in the eastern Taurides, southern Turkey. Journal of Micropalaeontology 26, 73–85, http://dx.doi.org/10.1144/JM.26.1.73.
9
Embry, A.F., Klovan, J.E., 1971. A late Devonian reef tract on northeastern Banks Island. N.W.T. Bulletin of Canadian Petroleum Geology 19 (4), 730–781. Fontaine, H., Ingavat, R., Vachard, D., 2017. Carboniferous corals from Northeast Thailand. Geological Society Malaysia Bulletin 15, 47–56. Fassihi, S., Sone, M., Hairapetian, V., Esfahani, F.S., 2017. Fusulinoids from Bashkirian–Moscovian transition beds of the Shahreza region in the Sanandaj–Sirjan Zone, Iran. International Journal of Earth Sciences (Geologische Rundschau) 106 (4), 1205–1221, http://dx.doi.org/ 10.1007/s00531-016-1435-8. Folk, R.L., 1959. Practical petrographical classification of limestone. American Association of Petroleum Geologist Bulletin 43, 1–38. Folk, R.L., 1962. Spectral subdivision of limestone types. In: Ham, W.E. (Ed.), Classification of carbonate rocks. American Association of Petroleum Geologist Memoir 1. , pp. 62–84. Fontaine, H., 1990. Carboniferous corals from northeast Thailand (northeast of Loei). Geologisches Jahrbuch Reihe B, Heft 73, 81–89. Fontaine, H., Suteethorn, V., Jongkanjanasoontorn, Y., 1991. Carboniferous corals of Thailand. CCOP Technical Bulletin 22 (82 p.). Fontaine, H., Suteethorn, V., Vachard, D., 1995. The Carboniferous of northeast Thailand: a review with new data. Journal of Southeast Asian Earth Sciences 12 (l/2) (l–l17). Fontaine, H., Salyapongse, S., Suteethorn, V., Tian, P., Vachard, D., 2005. Sedimentary rocks of the Loei area, Northeast Thailand: stratigraphy, paleontology and sedimentology. Bureau of Geological Survey, Department of Mineral Resources, Bangkok (167 p.). Fontaine, H., Suteethorn, V., 2000. Moscovian to Gzhelian coral assemblages in northeastern Thailand: field–relationship between Carboniferous and Permian strata. Journal of the Geological Society of Thailand 2000 (1), 34–41. Gong, E., Samankassou, E., Guan, C., Zhang, Y., Sun, B., 2007. Paleoecology of Pennsylvanian phylloid algal buildups in south Guizhou, China. Facies 53, 615–623. Kobayashi, E., 2011. Two species of Profusulinella (P. aljutovica and P. ovata), early Moscovian (Pennsylvanian) fusulines from southern Turkey and subdivision of primitive groups of the family fusulinidae. Rivista Italiana di Paleontologia e Stratigrafia 117 (1), 29–37. Kossovaya, O., 2015. Middle Urals. Carboniferous and Permian marine and continental successions: Field trip guidebook of XVIII International Congress of the Carboniferous and Permian (ICCP 2015). Perm: August 16–19, 2015/Perm: Printing house “Aster”., http://dx.doi.org/10.13140/RG.2.1.4043.1447 (112 p.). Krainer, K., Vachard, D., Lucas, S.G., 2003. Microfacies and microfossil assemblages (smaller foraminifers, algae, pseudoalgae) of the Hueco Group and Laborcita Formation (Upper Pennsylvanian–Lower Permian), south-Central New Mexico, USA. Rivista Italiana de Stratigrafia i Paleontologia 109, 3–36. Leven, E., Ja Gorgij, M.N., 2011. Fusulinids and stratigraphy of the Carboniferous and Permian in Iran. Stratigraphy and Geological Correlation 19 (7), 687–776. Mamet, B., Villa, E., 2004. Calcareous marine algae from the Carboniferous (Moscovian–Gzhelian) of the Cantabrian Zone (NW Spain) [Algas calcáreas marinas del Carbonífero (Moscoviense-Gzheliense) de la Zona Cantábrica (NO de ˜ ˜ Espana)]. Revista Espanola de Paleontología 19 (2), 151–190. Perm State University, 2015. Middle Urals. Carboniferous and Permian marine and continental successions: Field trip guidebook of XVIII International Congress of the Carboniferous and Permian (ICCP 2015). Perm: August 16–19, 2015/Perm: Printing house “Aster” (112 p.). Samankassou, E., 2003. Upper Carboniferous–Lower Permian buildups of the Carnic Alps, Austria–Italy. Permo–Carboniferous carbonate platforms and reefs. SEPM Special Publication 78, 201–217. Ueno, K., Charoentitirat, T., 2011. Carboniferous and Permian. In: Ridd, M.F., Barber, A.J., Crow, M.J. (Eds.), The Geology of Thailand. The Geological Society of London, pp. 71–136. Vachard, D., 1991. Parathurmminides et moravamminides (Microproblematica) de l’Emsien supérieur de la Formation Moniello (Cordillères Cantabrique, Espagne). Revue de Paléobiologie 10 (2), 255–299. Vachard, D., 2009. Beresellales, a discussed group of microproblematic algae. In: Fontaine, H., Hoang, T.T., Juanngam, S., Kavinate, S., Suteethorn, V., Vachard, D. (Eds.), Paleontology and stratigraphy of the Northwest Thailand: paleogeographical implications. Department of Mineral Resources, Bangkok, pp. 199–207. ˙ Vachard, D., Gaillot, J., Pille, L., Blazejowski, B., 2006. Problems on Biseriamminoidea, Mississippian–Permian biserially coiled foraminifera. A reappraisal with pro˜ Micropaleontología 38, 453–492. posals. Revista Espanola Wray, J.L., 1977. Calcareous algae. Elsevier Publishers, Amsterdam (190 p.).
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
ARTICLE IN PRESS Annales de Paléontologie xxx (2019) xxx–xxx
Disponible en ligne sur
ScienceDirect www.sciencedirect.com
Original article
Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand Stratigraphie et paléontologie des séquences du Carbonifère Moyen de Phu Bo Bit dans la province de Loei en Thaïlande Sathaporn Kavinate a,b,∗ , Mongkol Udchachon a,c , Henri Fontaine d a
Department of Biology, Faculty of Science, Mahasarakham University, 44150 Maha Sarakham, Thailand Department of Mineral Resources, 75/10 Rama VI, Rachathavi, 10400 Bangkok, Thailand c Palaeontological Research and Education Centre, Mahasarakham University, 44150 Maha Sarakham, Thailand d 128, rue du Bac, 75007 Paris, France b
a r t i c l e
i n f o
Article history: Received 30 November 2018 Accepted 12 July 2019 Available online xxx Keywords: Middle Carboniferous Palaeontology Stratigraphy Fusulinaceans Loei
a b s t r a c t The rocks from the Phu Bo Bit section consist of shale and limestone along with an abundant and diverse invertebrate fauna consisting of brachiopods, corals, bryozoans and crinoids, interpreted as having been deposited in shallow marine or shelf environments. At Phu Bo Bit, thick limestone lenses in shale contain microfossils. Based on the foraminiferan and algae assemblage, the stratigraphic sequence of Phu Bo Bit extends from the late Bashkirian to the early Moscovian. According to lithofacies and palaeontology, the Phu Bo Bit section represents the change from carbonate to siliciclastic sedimentation, which provides new evidence on the marine regression during the mid-Carboniferous. © 2019 Elsevier Masson SAS. All rights reserved.
r é s u m é Mots clés : Carbonifère moyen Paléontologie Stratigraphie Fusulines Loei
La séquence stratigraphique à Phu Bo Bit correspond à des schistes argileux et des calcaires renfermant une riche faune d’invertébrés, dont des brachiopodes, des coraux, des bryozoaires et des crinoïdes. En termes d’environnements de dépôt, ces sédiments se sont déposé dans un environnement marin de plateforme peu profond. Les lentilles calcaires contenues dans les schistes argileux renferment des microfossiles. Sur la base de la composition en foraminières et en algues fossiles, la séquence stratigraphique de Phu Bo Bit s’étend du Bashkirien supérieur au Moscovien inférieur. Les micro-lithofaciès et les assemblages paléontologiques montrent que la séquence passe d’une sédimentation carbonatée à silico-clastique, ce qui corresponds à l’hypothèse d’une régression marine durant le Carbonifère moyen. ´ ´ es. © 2019 Elsevier Masson SAS. Tous droits reserv
1. Introduction Carboniferous sedimentary rocks are widely exposed in several areas of Thailand and were deposited in widely diverse environments (Ueno and Charoentitirat, 2011; Fontaine et al., 1991, 2005). The Loei area is one of the key areas in Thailand with a good expo-
∗ Corresponding author. Department of Biology, Faculty Mahasarakham University, 44150 Maha Sarakham, Thailand. E-mail address: [email protected] (S. Kavinate).
of
Science,
sure of Carboniferous rock succession, but few reports on detailed stratigraphy and palaeontology have been published so far. They contain marine microfossils (foraminiferans and algae) and frequently corals, which are common in the Indochina Block. The Phu Bo Bit sequence, Muang District, in Loei Province studied in the present paper was previously reported by Fontaine and co-authors in 2005, it contains diverse fossils, including corals (Fontaine et al., 1990, 1991), algae and foraminiferans corresponding to the late Bashkirian to early Moscovian (Fontaine et al., 2005). The purpose of this study is to investigate the geology, sedimentology, stratigraphy and palaeontology in order to interpret the depositional
https://doi.org/10.1016/j.annpal.2019.08.001 0753-3969/© 2019 Elsevier Masson SAS. All rights reserved.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
2
Fig. 1. Topographic map of the Phu Bo Bit located east of Muang district, Loei Province. Sampling locations are indicated with solid circles. Carte topographique de Phu Bo Bit à l’Est du district de Muang dans la province Loei. La localisation des échantillonnages est représentée par des cercles pleins.
environment of the ‘middle’ Carboniferous in the Loei area. Most materials studied herein have been collected by Fontaine (localities 1 to 7 (Fontaine et al., 2005)), with one additional locality (locality 8) and the thin sections from these localities are studied for the first time (Fig. 1). Materials in this study are deposited in the Palaeontological Research and Education Centre, Mahasarakham University, Thailand. 2. Geological setting The Phu Bo Bit section was mapped in one measured section oriented approximately in an east-west direction as shown in Fig. 1. The total length of section was about 5 km. Rock samples were collected for detailed petrographic study. The representative sedimentary sequence of the section at Phu Bo Bit is shown in Fig. 2. Two rock units may be identified from the fieldwork and the description of each unit is presented in ascending order as follows: A hill 2 km east of Loei consists of thick limestone lenses in shale containing foraminiferans, Tabulata and solitary Rugosa. They have
been assigned to the Upper Bashkirian (Fontaine et al., 1991, 1995, 2005). Along the northern base of Phu Pho Bit, a section of shale, calcareous mudstone, argillaceous limestone, limestone and sandstone is well exposed along the road from Ban Na Bon (5 km south of Pha Tha) to Ban Phia. It is rich in fossils at many levels: foraminiferans, solitary Rugosa with and without dissepiments, Chaetetes, bryozoans, brachiopods and gastropods (Fig. 3). Beds dip towards the east. Samples have been collected from west to east. Fossils have been collected at six localities among eight investigated (Fig. 4). At the eighth locality (Fig. 1; 792551E, 1937839N; samples LST015 to LST017), 2 km east of Ban Na Bon, in a small limestone quarry, small lenses of black limestone occur in the shale. Limestone is packstone, again very rich in tubular algae and fusulinaceans. At the first locality (Fig. 1; 793900E, 1937300N; samples T7795 to T7797), argillaceous limestone and calcareous mudstone contain diverse fossils: dissepimented solitary corals, bryozoans,
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
3
Fig. 2. Lithostratigraphic column of Phu Bo Bit showing intercalation of late Bashkirian through Moscovian shale and limestone. The main stratigraphic column is based on Charoenprawat and Wongwanich, 1976. Colonne stratigraphique à Phu Bo Bit montrant la séquence carbonatée et argileuse du Bashkirien au Moscovien. La colonne stratigraphique est basée sur les travaux de Charoenprawat et Wongwanich, 1976.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9 4
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
Fig. 3. A. Field photographs showing view from south of Phu Bo Bit. B. Contact of siliceous shale and very thick-bedded limestone in the middle part of the Phu Bo Bit section. C. A quarry near the foothill of Phu Bo Bit showing exposure of limestone. D. A colony of tabulate coral. E. Massive rugose coral and F. Solitary coral at Phu Bo Bit section. A. Photographie de terrain dans la partie Sud de Phu Bo Bit. B. Contact entre schistes argileux siliceux et épais banc calcaire dans le milieu de la section de Phu Bo Bit section. C. Carrière à la base de la coline de Phu Bo Phit montrant des affleurements calcaires. D. Colonie de corail tabulé. E. Corail rugueux massif F. Corail solitaire de la section de Phu Bo Bit.
brachiopods and gastropods. Fragments of algae and fusulinaceans are rare and poorly preserved. At the second locality (Fig. 1; 794300E, 1937500N; samples T7641 to T7650), a dark grey limestone is associated with shale and sandstone. It is locally very rich in fossils. Algae (Beresella erecta Maslov & Kulik, 1956) are commonly in great abundance similar to those of the Moscovian limestone exposed in a pond at Ban Na Duang about 15 kilometers east of Loei (Fontaine and Suteethorn, 2000). Other fossils are rare and include smaller foraminifera (Nodosariidae), fusulinaceans, dissepimented solitary corals and crinoids. At the third locality (Fig. 1; 794200E, 1937500N; samples T7798 to T7801), 2.3 km east of Ban Na Bon, limestone beds in shale contain very rare dissepimented solitary corals. Algae are still in abundance but fusulinaceans are very rare. At the fourth locality (Fig. 1; 794800E, 1937700N; sample T7802), shale without fossils is present. At the fifth locality (Fig. 1; 796300E, 1937400N; samples T7803 to T7805), 3.5 km east of Ban Na Bon, small lenses of black limestone
occur within the shale. Limestone is packstone, again very rich in tubular algae and with rare fusulinaceans (T7805). At the sixth locality (Fig. 1; 797100E, 1936300N; sample T7806), shale with sandstone intercalations is present. At the seventh locality (Fig. 1; 797900E, 1936100N; samples T7807 to T7812), small limestone (wackestone to packstone) lenses in shale contain calcispheres, smaller foraminifera (Globivalvulina), scattered and poorly preserved fusulinaceans (Profusulinella sp.), Chaetetes, Multithecopora and solitary corals with and without dissepiments. The shale is locally rich in brachiopods. The solitary corals with dissepiments belong to Caninophyllum. They are about 3 cm in diameter, with 40 to 44 major septa and extremely short minor septa. Dissepiments are arranged in about 8 rows. Other solitary corals are small, 5 to 6 mm in diameter. They display a columella and probably belong to Amygdalophylloides. Chaetetes consists of two species: a species with corallites 0.6 mm in diameter, the other species with corallites 0.4 mm in diameter. The corallites of Multithecopora are 1.5 mm in diameter.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
5
Fig. 4. A and B. A rock slab and photomicrograph of sample no. LST18 showing fusulinid and bioclastic fragments. C and D. A rock slab and photomicrograph of sample no. LST021 showing algal and bioclastic fragments dispersed in micrite matrix of microfacies. E and F. A rock slab and photomicrograph of sample no. LST015 showing fusulinid and bioclastic fragments from Phu Bo Bit section. Scale bar = 1 mm. A et B. Section de roche et microphotographie de l’échantillon no LST18 montrant des Fusulinidae et des bioclastes. C et D. Section de roche et microphotographie de l’échantillon LST021 montrant des algues et des bioclastes dans une matrice micritique. E et F. Section de roche et microphotographie de l’échantillon LST015 montrant des fusulinidés et des bioclastes de la séquence de Phu Bo Bit. Barre d’échelle = 1 mm.
Taxa of major fossil groups observed in the Phu Bo Bit Section are summarized in Table 1. 3. Systematic Palaeontology 3.1. Foraminifera Phylum PROTOZOA Class SARCODINA Order FORAMINIFERIDA Eichwald, 1830 Suborder FUSULININA Wedekind, 1937 Superfamily FUSULINACEA Moller, 1878 Family PSUDOSTAFFELLIDAE Putria, 1956 Subfamily FUSULINELLINAE Staff and Wedekind, 1910 Genus Profusulinella Rauser and Beliaev, 1936 Profusulinella sp. (Figs. 5A–G and 6A–C)
Description. Shell minute, inflated fusiform to subellipsoidal, with bluntly rounded poles. Mature specimens possess 4–6 volutions and measure from 0.9 to 1.25 mm in length and from 0.5 to 1 mm in diameter. Tunnel rather narrow, about half as high as chambers. Chomata massive and wide. Age/Remarks. Carboniferous, late Bashkirian to early Moscovian. Occurrence: Phu Bo Bit, Samples LST015 to LST017. Profusulinella rhombiformis; is reported in the valley of the Nam Huai, 3 km east of Ban Tat So area, northeast of Loei (Fontaine, 1990) and Ban Tha Sot, 38 km north-northeast of Loei (Fontaine et al., 1982). The genus Profusulinella is reported worldwide; in Russia (upper Bashkirian to lower Moscovian; Geology of Russia, 1963), in Anarak Section of Central Iran (late Bashkirian–early Moscovian; Fassihi et al., 2017), southern and northern Urals (Moscovian; Dzhenchuraeva and Okuyucu, 2007) and southern Turkey (early Moscovian; Kobayashi, 2011) which indicates a tropical shallow marine platform during the mid-Carboniferous.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
6
Table 1 Taxa of major fossil groups observed in the Phu Bo Bit Section. Taxons des principaux groupes fossiles observés dans la section de Phu Bo Bit. Age Pennsylvanian Carboniferous Moscovian
Fossils
Algae Foraminifer Small foraminifera
Corals
Bashkirian
Algae Foraminifera
Small foraminifera
Corals Other fossils
Beresella sp. Profusulinella sp. Bradyina sp. Climacammina sp. Endothyra sp. Caninophyllum sp. Caninia sp. Multithecopora Beresella sp. Profusulinella sp. Eostaffella sp. Ozawainella sp. Climacammina sp. Globivalvulina sp. Bradyina sp. Endothyra sp. Chaetetes sp. Multithecopora sp. Brachiopods Bryozoans Gastropods Ostracods Crinoids Trilobites
Family OZAWAINELLIDAE Thompson & Foster, 1937 Genus Ozawainella Thompson, 1935 Ozawainella sp. (Fig. 6D) Description. Shell umbilicate to spherical or elongate, evolute in early forms, involute or irregularly uncoiled in later ones, axis of coiling short or long, first few volutions discoidal, others spherical to unevenly elongate; spirotheca composed of tectum with upper and lower tectoria in early forms but diaphanotheca occurring below tectum and above lower tectorium in later ones; septa plane; shell generally planispiral but may be asymmetrical, discoidal in at least part of shell with coiling axis in shortest diameter; tunnel singular. Age/Remarks. Late Mississippian–‘late’ Permian (Lopingian). Occurrence. Phu Bo Bit, Samples LST016 and LST018. This genus suggests a latest Bashkirian–earliest Moscovian age comparable to the Melekessian–Vereian transition in the Russian Platform (Fassihi et al., 2017). Ozawainella pararhomboidalis was reported from the Bashkirian Stage (Dzhenchuraeva and Okuyucu, 2007). Ozawainella occurs in Central Asia in the late Bashkirian–early Moscovian. Superfamily ENDOTHYRACEA Brady, 1884 Family ENDOTHYRIDEA Brady, 1884 Subfamily ENDOTHYRINAE Brady, 1884 Genus Endothyra Phillips, 1846 Endothyra sp. (Fig. 5G, from the Phu Bo Bit section) Description. Test enrolled, partially involute, plane of coiling changes during growth, turning through 30–90◦ , may turn gradually as in plectogyral coiling, or abruptly nearly 90◦ , few chambers to whorl, whorls few; wall calcareous, with 2 layers, thin dark outer layer (tectum) and thicker, fibrous alveolar, inner layer
(diaphanotheca); partial recrystallization may result in a granular appearance, secondary deposits in form of nodes, ridges, or forward directed hooks secreted on chamber floors; external aperture not always evident, but an interiomarginal, equatorial to asymmetrical slit may be present, relatively large intercameral foramina in same position. Late Devonian (Famennian), Early Age/Remarks. Carboniferous–Permian. Occurrence. Phu Bo Bit, Sample LST016. This genus has been reported worldwide such as Endothyra bradyi from central Urals (Bashkirian–Moscovian; Perm State University, 2015), Endothyra ex gr. bowmani (Serpukhovian) from southern Urals and Endothyra rzhevica from Russia (Serpukhovian and Serpukhovian-lower Bashkirian; Davydov, 2008) Family BISERIAMMINIDAE Chernysheva, 1941 Genus Globivalvulina Schubert, 1921 Globivalvulina sp. (Fig. 5F) Description. Test biserial, involute; aperture at inner border of septal face. Age/Remarks. Early Carboniferous (Mississippian)–Permian. Occurrence. Phu Bo Bit, Sample LST016. This genus is found worldwide. It was reported from the central Urals (Bashkirian–Moscovian; Perm State University, 2015). Bozorgnia (1973) attributed the smaller foraminiferans occurring in sediments of the Dozdehband formation in Iran to this genus, suggesting that the upper part of the sequence in question is probably of early Bashkirian age (Leven and Gorgij, 2011). In China, the genus was reported from the Early Carboniferous–Permian (Vachard et al., 2006). 3.2. Algae Order BERESELLALES Maslov and Kulik, 1956nomen translat. herein Family BERESELLACEAE Maslov and Kulik, 1956 nomen translat. H. Termier et al., 1977 see also G. Termier et al., 1977, p. 141 (ex tribe)orth mut. Shuysky, 1985 (ex Beresellidae) (non Deloffre, 1987, nec Shuysky, 1987, nec Deloffre, 1988) Tribe Bereselleae Maslov and Kulik, 1956 Genus Beresella Makhaev, 1937 ex Maslov and Kulik, 1956 Beresella sp. (Figs.5C and 6E) Description. Cylindrical microproblematic algae, undivided but with internal diaphragms more or less numerous. The tubular undivided skeletons are occasionally bifurcated, and have an outer smooth or finely costulate surface, and an internal cavity. In between, the re-entrants, darker rings, are finely canaliculate. The canalicules are blind, because they are overlain by a continuous external layer (Vachard, 1991, 2009). Age/Remarks. Late Carboniferous (Pennsylvanian) Occurrence. Phu Bo Bit, Samples LST015 and T7589. This genus is reported worldwide; such as from the Kuzuoluk section of Southern Turkey (Bashkirian–Moscovian), including Beresella erecta Maslov and Kulik, 1956 and Beresella ishimica Kulik, 1964 (Dzhenchuraeva and Okuyucu, 2007). It has been recorded in Spain from the upper part of the Picos de Europa Formation at Las Llacerias section, in the late Moscovian beds (Myachkovian) (Mamet and Villa, 2004) and in the central Urals (Bashkirian–Moscovian; Kossovaya, 2015), which indicates shallow-marine palaeoenvironments (Wray, 1977; Krainer et al., 2003). Beresella sp. is also
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
7
Fig. 5. Fusulinids from the Phu Bo Bit Section (late Bashkirian to early Moscovian). A. Profusulinella sp. (Sample LST015). B. Profusulinella sp. (Sample LST015). C. Beresella erecta and Profusulinella sp. (Sample LST015). D. Profusulinella sp. (Sample LST016). E. Profusulinella sp. (Sample LST015). F. Profusulinella sp. and Globivalvulina sp. (Sample LST016). G. Profusulinella sp. and Endothyra sp. (Sample LST016). Scale bar = 1 mm. Fusulinidés de la séquence de Phu Bo Bit (late Bashkirian to early Moscovian). A. Profusulinella sp. (échantillon LST015). B. Profusulinella sp. (échantillon LST015). C. Beresella erecta et Profusulinella sp. (échantillon LST015). D. Profusulinella sp. (échantillon LST016). E. Profusulinella sp. (échantillon LST015). F. Profusulinella sp. et Globivalvulina sp. (échantillon LST016). G. Profusulinella sp. et Endothyra sp. (échantillon LST016). Barre d’échelle = 1 mm.
reported from a Pennsylvanian algal reef in south Guizhou, China (Gong et al., 2007), a Moscovian algal mound from Tarim, NW China (Chen, 2012) and Pennsylvanian algal buildups of the Carnic Alps, Austria (Samankassou, 2003). 4. Brief description of the microfacies of limestone Lithology investigation and observations are combined with microfacies studies. It consists of the description and interpretation of the sedimentary facies as well as the occurrence and composition of the biota. This information is the basis for reconstruction of the depositional settings.
Carbonate textures and allochemical constituents are observed in thin sections under a petrographic microscope. The facies types are defined on the basis of lithology, allochemical constituents, texture, and fossil associations in order to reconstruct their depositional environment. Carbonate rock classification developed either by Folk (1959, 1962) or Dunham (1962) and also Embry and Klovan (1971) were applied for limestone classification in this study. As a result, five microfacies types are recognized for limestones from the Phu Bo Bit section including Microfacies I, algal lamination; Microfacies, II pelmicrite; Microfacies III, sparse biomicrite; Microfacies IV, packed biomicrite and Microfacies V, biosparite. The lithological characteristics and depositional environments of these microfacies are summarized in Table 2.
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
8
Fig. 6. Fusulinids and algae from the Phu Bo Bit section (late Bashkirian to early Moscovian). A. Profusulinella sp. (Sample LST017). B. Profusulinella sp. (Sample LST016). C. Profusulinella sp. (Sample LST018). D. Ozawainella sp. (centre and centre right, Sample LST018). E. Beresella sp., longitudinal section and transverse section (Sample T7589). Scale bar = 1 mm. Fusulinidés et algues de la séquence de Phu Bo Bit (Bashkirien supérieur à Moscovien inférieur). A. Profusulinella sp. (échantillon LST017). B. Profusulinella sp. (échantillon LST016). C. Profusulinella sp. (échantillon LST018). D. Ozawainella sp. (au centre et au centre droit, échantillon LST018). E. Beresella sp., sections longitudinale et transverse (échantillon T7589). Barre d’échelle = 1 mm.
Table 2 Summary of the microfacies types identified in the study area and their interpretation in terms of depositional environments. Résumé des types de microfaciès rencontrés dans la section et interprétation en termes d’environnement de dépôt. Microfacies
Lithological characteristics
Depositional environments
I Algal lamination II Pelmicrite III Sparse biomicrite
Very thin-laminae, decayed algae, detrital quartz grains Discrete peloids, fine fossil fragments Poorly sorted, floating grains, micrite matrix
IV Packed biomicrite
In-situ deposition of unfragmented fossils, micrite matrix, fragmentary fossils, intraclasts, carbonaceous matter Intraclasts, fragmented and unfragmented fossils, lumped pellets, poorly to moderately sorted
Shallow subtidal Subtidal zone of inner shelf, low-water energy Subtidal and/or subwave base of a shelf sea close to the shore Subtidal zone below the active wave base
V Biosparite
Intertidal to near shore subtidal above the wave base
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001
G Model ANNPAL-2362; No. of Pages 9
ARTICLE IN PRESS S. Kavinate et al. / Annales de Paléontologie xxx (2019) xxx–xxx
5. Conclusion The sequence on the northern base of the Phu Bo Bit, in Loei Province, Thailand contains abundant macrofossils (Tabulata (Chaetetes, Multithecopora), solitary Rugosa, bryozoans, brachiopods and gastropods), foraminiferan and algal microfossils. Based on the foraminiferan assemblage, especially fusulinaceans (Profusulinella sp. and Ozawainella sp.), Climacammina sp., Endothyra sp., Globivalvulina sp. and the dasyclad algae Beresella sp., the stratigraphic sequence of Phu Bo Bit extends from the late Bashkirian to the early Moscovian. The carbonate rocks in the study area are divided into five microfacies types based on limestone classification as well as carbonate textures. Excluding crystalline microfacies, packed biomicrite, sparse biomicrite, biosparite, pelmicrite and algal-lamination microfacies are present in decreasing order of abundance, representing the subtidal zone below the active wave base, the subtidal and/or subwave base of the shelf sea close to the shore, the intertidal to near shore subtidal zone above the wave base, the subtidal zone of inner shelf with low-water energy and the shallow subtidal depositional environments respectively. These microfacies represent carbonate facies developed under the influence of low to high energy seas in subtidal to intertidal regimes. Our study on the Phu Bo Bit sequence provides therefore geological evidence on the marine regression in Loei region during the middle Carboniferous (late Bashkirian to early Moscovian). Disclosure of interest The authors declare that they have no competing interest. Acknowledgements The authors would like to express their sincere gratitude to Dr. Varavudh Suteethorn and Mr. Pitaks Ratanajaruraks for their support and encouragement and for providing transportation facilities for our fieldwork. Thanks to two anonymous reviewers who provided helpful comments for good improvements to this manuscript and Dr. Clive Burrett who helped with English. References Bozorgnia, F., 1973. Paleozoic foraminiferal biostratigraphy of central and east Alborz Mountains, Iran. Geological Laboratories Publication 4. National Iranian Oil Company (185 p.). Charoenprawat, A., Wongwanich, T., 1976. Preliminary report on the geology of Changwat Loei (NE47-12), with geological map 1:250 000 scale: Department of Mineral Resources. Bangkok (in Thai). Chen, Z.Q., 2012. A Late Carboniferous algal mound from the Tarim Basin, NW China: internal structure and palaeoecology. Geological Journal 47, 477–494. Davydov, V.I., 2008. Fusulinid biostratigraphic dating of Upper Paleozoic samples from Novaya Zemlya (The Holtedahl collection). In: Arne Nakrem, H. (Ed.), Natural History Museum (Geology), University of Oslo. (27 p.). Dunham, R.J., 1962. Classification of carbonate rocks according to depositional texture. In: Ham, W.E. (Ed.), Classification of Carbonate Rocks. American Association of Petroleum Geologists Memoir 1. , pp. 108–121. Dzhenchuraeva, A.V., Okuyucu, C., 2007. Fusulinid Foraminifera of the Bashkirian–Moscovian boundary in the eastern Taurides, southern Turkey. Journal of Micropalaeontology 26, 73–85, http://dx.doi.org/10.1144/JM.26.1.73.
9
Embry, A.F., Klovan, J.E., 1971. A late Devonian reef tract on northeastern Banks Island. N.W.T. Bulletin of Canadian Petroleum Geology 19 (4), 730–781. Fontaine, H., Ingavat, R., Vachard, D., 2017. Carboniferous corals from Northeast Thailand. Geological Society Malaysia Bulletin 15, 47–56. Fassihi, S., Sone, M., Hairapetian, V., Esfahani, F.S., 2017. Fusulinoids from Bashkirian–Moscovian transition beds of the Shahreza region in the Sanandaj–Sirjan Zone, Iran. International Journal of Earth Sciences (Geologische Rundschau) 106 (4), 1205–1221, http://dx.doi.org/ 10.1007/s00531-016-1435-8. Folk, R.L., 1959. Practical petrographical classification of limestone. American Association of Petroleum Geologist Bulletin 43, 1–38. Folk, R.L., 1962. Spectral subdivision of limestone types. In: Ham, W.E. (Ed.), Classification of carbonate rocks. American Association of Petroleum Geologist Memoir 1. , pp. 62–84. Fontaine, H., 1990. Carboniferous corals from northeast Thailand (northeast of Loei). Geologisches Jahrbuch Reihe B, Heft 73, 81–89. Fontaine, H., Suteethorn, V., Jongkanjanasoontorn, Y., 1991. Carboniferous corals of Thailand. CCOP Technical Bulletin 22 (82 p.). Fontaine, H., Suteethorn, V., Vachard, D., 1995. The Carboniferous of northeast Thailand: a review with new data. Journal of Southeast Asian Earth Sciences 12 (l/2) (l–l17). Fontaine, H., Salyapongse, S., Suteethorn, V., Tian, P., Vachard, D., 2005. Sedimentary rocks of the Loei area, Northeast Thailand: stratigraphy, paleontology and sedimentology. Bureau of Geological Survey, Department of Mineral Resources, Bangkok (167 p.). Fontaine, H., Suteethorn, V., 2000. Moscovian to Gzhelian coral assemblages in northeastern Thailand: field–relationship between Carboniferous and Permian strata. Journal of the Geological Society of Thailand 2000 (1), 34–41. Gong, E., Samankassou, E., Guan, C., Zhang, Y., Sun, B., 2007. Paleoecology of Pennsylvanian phylloid algal buildups in south Guizhou, China. Facies 53, 615–623. Kobayashi, E., 2011. Two species of Profusulinella (P. aljutovica and P. ovata), early Moscovian (Pennsylvanian) fusulines from southern Turkey and subdivision of primitive groups of the family fusulinidae. Rivista Italiana di Paleontologia e Stratigrafia 117 (1), 29–37. Kossovaya, O., 2015. Middle Urals. Carboniferous and Permian marine and continental successions: Field trip guidebook of XVIII International Congress of the Carboniferous and Permian (ICCP 2015). Perm: August 16–19, 2015/Perm: Printing house “Aster”., http://dx.doi.org/10.13140/RG.2.1.4043.1447 (112 p.). Krainer, K., Vachard, D., Lucas, S.G., 2003. Microfacies and microfossil assemblages (smaller foraminifers, algae, pseudoalgae) of the Hueco Group and Laborcita Formation (Upper Pennsylvanian–Lower Permian), south-Central New Mexico, USA. Rivista Italiana de Stratigrafia i Paleontologia 109, 3–36. Leven, E., Ja Gorgij, M.N., 2011. Fusulinids and stratigraphy of the Carboniferous and Permian in Iran. Stratigraphy and Geological Correlation 19 (7), 687–776. Mamet, B., Villa, E., 2004. Calcareous marine algae from the Carboniferous (Moscovian–Gzhelian) of the Cantabrian Zone (NW Spain) [Algas calcáreas marinas del Carbonífero (Moscoviense-Gzheliense) de la Zona Cantábrica (NO de ˜ ˜ Espana)]. Revista Espanola de Paleontología 19 (2), 151–190. Perm State University, 2015. Middle Urals. Carboniferous and Permian marine and continental successions: Field trip guidebook of XVIII International Congress of the Carboniferous and Permian (ICCP 2015). Perm: August 16–19, 2015/Perm: Printing house “Aster” (112 p.). Samankassou, E., 2003. Upper Carboniferous–Lower Permian buildups of the Carnic Alps, Austria–Italy. Permo–Carboniferous carbonate platforms and reefs. SEPM Special Publication 78, 201–217. Ueno, K., Charoentitirat, T., 2011. Carboniferous and Permian. In: Ridd, M.F., Barber, A.J., Crow, M.J. (Eds.), The Geology of Thailand. The Geological Society of London, pp. 71–136. Vachard, D., 1991. Parathurmminides et moravamminides (Microproblematica) de l’Emsien supérieur de la Formation Moniello (Cordillères Cantabrique, Espagne). Revue de Paléobiologie 10 (2), 255–299. Vachard, D., 2009. Beresellales, a discussed group of microproblematic algae. In: Fontaine, H., Hoang, T.T., Juanngam, S., Kavinate, S., Suteethorn, V., Vachard, D. (Eds.), Paleontology and stratigraphy of the Northwest Thailand: paleogeographical implications. Department of Mineral Resources, Bangkok, pp. 199–207. ˙ Vachard, D., Gaillot, J., Pille, L., Blazejowski, B., 2006. Problems on Biseriamminoidea, Mississippian–Permian biserially coiled foraminifera. A reappraisal with pro˜ Micropaleontología 38, 453–492. posals. Revista Espanola Wray, J.L., 1977. Calcareous algae. Elsevier Publishers, Amsterdam (190 p.).
Please cite this article in press as: Kavinate, S., et al., Stratigraphy and Palaeontology of mid-Carboniferous Sequences at Phu Bo Bit in Loei Province, Thailand. Annales de Paléontologie (2019), https://doi.org/10.1016/j.annpal.2019.08.001