Palynofloral changes in the Upper Paleozoic and Mesozoic of the Deocha-Pachami area, Birbhum Coalfield, West Bengal, India
Tóm tắt
The study of Upper Paleozoic and Mesozoic palynomorphs in three boreholes from the Deocha-Pachami area, Birbhum Coalfield, West Bengal, India, has allowed dating of the Talchir, Barakar, Dubrajpur, and Rajmahal formations, and revealed many hiatuses. The lowermost unit, the Talchir Formation, yielded earliest Permian palynomorphs. The Barakar Formation, which includes coal-bearing strata, was previously dated as Early Permian. However, data presented herein indicate an Early Permian to earliest Triassic age for this unit-containing actually the Karharbari, Barakar s.s., Kulti, and Ranigang formations as well as the basal part of the Panchet Formation. The overlying Dubrajpur Formation is Jurassic (Callovian to Tithonian), with an unconformity at its base. The uppermost Dubrajpur Formation is Tithonian-Berriasian. The palynomorphs from the intertrappeans within the Rajmahal Formation suggest an Early Cretaceous age. The revised ages of the Barakar and Dubrajpur formations are of major regional significance. The distribution patterns of spore-pollen may provide a broad spectrum of paleoclimate during Permian, Late Jurassic, and Early Cretaceous times, as there is no record of marine signatures in the study area.
Tài liệu tham khảo
Vijaya. Search for Jurassic in subsurface Mesozoic sediments Birbhum District, West Bengal. In: Proceedings XVI Indian Colloquium on Micropaleontology and Stratigraphy. Bull ONGC, 2000, 37: 127–135
Vijaya. Palynostratigraphy of the Permian Coal Measures and the Mesozoic succession in Borehole DPD-6, Pachami area, West Bengal, India. Palaeontographica, 2004, 267: 33–55
Vijaya, Sen K K. Palynological study of the Dubrajpur Formation in the Mesozoic succession, Pachami area, Birbhum Coalfield, West Bengal. J Palaeontol Soc India, 2005, 50(1): 121–133
Sen K K, Datta R K, Bandopadhaya S K. Birbhum coalfield—A major coalfield discovered. Proceedings of the National Seminar on Coal Resources of India, 1987. 417–427
Tiwari R S, Singh, Vijaya. Palynological evidences for Permo-Triassic boundary in Raniganj Coalfield, Damodar Basin, India. Bull Geol Min Metal Soc, 1986, 54: 256–264
Tiwari R S, Kumar R. Indian Gondwana palynology: Relationships and chronocalibration. Palaeobotanis, 2002, 51:13–30
Burger D. Timescales 8. Jurassic Australian Phanerozoic Timescales, Biostratigraphic Charts and Explanatory Notes. Second series. Bureau of Mineral Resources, Australia Record, 1995, 37: 30
Vijaya. Palynological dating of the Neocomian-Aptian succession in the Indian Peninsula. Cretaceous Res, 1999, 20: 597–608
Sen K K. Birbhum Coal Basin: its evolution, stratigraphy and coal potentiality—An overview. Geol Surv India Spec Publ, 1996. 20: 49–56
Vijaya. Advent of Gondwana deposition of Indian peninsula: A palynological reflection and relationship. Proceedings Ninth International Gondwana Symposium, 1996. 283–298
Tiwari R S, Tripathi A. Marker assemblage-zones of spore and pollen species through Gondwana Palaeozoic and Mesozoic sequence in India. Palaeobotanist, 1992, 40: 194–236
Tiwari R S, Tripathi A. Palynological zones and their climatic inference in the coal bearing Gondwana of Peninsular India. Palaeobotanist, 1988, 36: 87–101
Venkatchala B S, Tiwari R S, Vijaya. Diversification of spore-pollen “character states” in the Indian Permian. Rev Palaeobot Palynol, 1995, 85: 319–340
Tiwari R S, Vijaya. Synchroneity of palynological events and patterns of extinction at Permo-Triassic boundary in terrestrial sequence of India. In: Guex J, Baud A, eds. Recent Developments on Triassic Stratigraphy. Proceedings Triassic Symposium, Memoires de Geologie, 1994. 139–154
Vijaya, Tiwari R S. Role of spore-pollen species in demarcating the Permo-Triassic boundary in Raniganj Coalfield, West Bengal, India. Palaeobotanist, 1987, 35: 242–248
Tiwari R S, Vijaya. Permo-Triassic boundary on the Indian peninsula. In: Sweet W C, Zunyi Y, Dickins J M, eds. Permo-Triassic Events in the Eastern Tethys, 1992. 37–45
Stephenson M H, Osterloff P L, Filatoff J. Palynological biozonation of the Permian of Oman and Saudi Arabia: Progress and challenges. Geo Arabia, 2003, 8: 467–496
Vijaya, Bhattacharji T K. Palynological evidence for Jurassic strata in the Panagarh area, West Bengal, India. J Asian Earth Sci, 2003, 21: 1171–1190
Helby R J, Morgan R, Partridge A D. A palynological zonation of the Australian Mesozoic. Mem Ass Australasian Palaeont, 1987, 4: 1–94
Burger D. Timescales 9. Cretaceous Australian Phanerozoic Timescales, Biostratigraphic charts and Explanatory Notes. Second Series. Bureau of Mineval Resources, Australia Record, 1995, 38: 35
Singh H P, Venkatachala B S. Upper Jurassic-Lower Cretaceous spore-pollen assemblages in peninsular India. Palaeobotanist, 1988, 36: 168–176
Ramanujam C G K. Spores and pollen suits of some Upper Gondwana deposits of South India-A critical appraisal. Gondwana Geol Mag Spe Volume, 1993. 462–478
Vijaya. Carboniferous-Permian event: Rise of the Glossopteris flora on Gondwanaland. Palaeoworld, 1998, 9: 77–86
Vijaya, Bhattacharji T K. An Early Cretaceous age for Rajmahal Traps, Panagarh area, West Bengal: Palynological evidence. Cretaceous Res, 2002, 23: 789–805
Vijaya. Recognition of potential palynoevents in the Jurassic Sequence of India and their Correlation in Australia. In: Hall R L, Smith P L, eds. Proceedings 5th International Sympositum on the Jurassic System, 2000. 237–248
Abbink O A, Van Konijnenburg-Van Cittert J H A, Visscher H. A sporomorph ecogroup model for the Northwest European Jurassic-Lower Cretaceous: Concepts and framework. Netherlands J Geosci / Geologie en Mijnbouw, 2004, 83(1): 17–38