气候变化领域集成服务门户(CCPortal): Sedimentology and basin-fill history of the Cenozoic succession of the Sylhet Trough; Bengal Basin; Bangladesh

CCPortal

DOI	10.1007/s00531-020-01946-1
	Sedimentology and basin-fill history of the Cenozoic succession of the Sylhet Trough; Bengal Basin; Bangladesh
	Khanam F.; Rahman M.J.J.; Alam M.M.; Abdullah R.
发表日期	2020
ISSN	14373254
英文摘要	The Sylhet Trough, a petroleum province of the Bengal Basin, accommodates a huge thickness of Eocene to Recent sedimentary successions. However, the basin-fill history of the trough is poorly understood; specifically, constrains on timing of deposition of the individual units are yet to be established. Therefore, we aimed at establishing sedimentation and basin-fill history of the Sylhet Trough based on detailed lithofacies analysis of the outcropping Cenozoic succession. We have divided the entire Cenozoic succession into three megasequences which can be further sub-divided into nine lithostratigraphic units based on bounding discontinuities, such as transgressive erosion surface, regressive erosion surface, transgressive surface, marine flooding surface, and incised valley floor. The oldest is the Megasequence 1, comprised of shallow marine shelfal deposits overlain by shallow marine to nearshore deposits. In the middle, the Megasequence 2 is representing tide-dominated marine to coastal (deltaic) depositional systems with evidence of cyclic marine regression and transgression. Repetitive occurrence of incised channel, tidal inlet, tidal ridge/shoal, tidal flat and other tidal deposits are separated by shelfal deposits. The top of the Megasequence 2 is marked by a pronounced erosion surface interpreted as an incised valley floor indicating the final phase of marine regression followed by the gradual establishment of the overlying continental-fluvial depositional systems (i.e., the Megasequence 3). This youngest megasequence is characterized by stacked braided river sand bars that pass up-sequence into meandering river deposits. Based on the Cenozoic eustatic sea level curve, we suggest that the upper boundaries of the Megasequence 1 and Megasequence 2 are approximately at 39.5 Ma and 5.0 Ma, respectively. © 2020, Geologische Vereinigung e.V. (GV).
英文关键词	Bengal Basin; Bounding discontinuity; Cenozoic succession; Depositional environment; Facies assemblages; Sequence stratigraphy
语种	英语
来源期刊	International Journal of Earth Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/147748
作者单位	Geophysical Division, Bangladesh Petroleum Exploration and Production Company Ltd. (BAPEX), Dhaka, Bangladesh; Department of Geological Sciences, Jahangirnagar University, Savar, Dhaka, 1342, Bangladesh; Department of Geology, Dhaka University, Dhaka, 1000, Bangladesh
推荐引用方式 GB/T 7714	Khanam F.,Rahman M.J.J.,Alam M.M.,et al. Sedimentology and basin-fill history of the Cenozoic succession of the Sylhet Trough; Bengal Basin; Bangladesh[J],2020.
APA	Khanam F.,Rahman M.J.J.,Alam M.M.,&Abdullah R..(2020).Sedimentology and basin-fill history of the Cenozoic succession of the Sylhet Trough; Bengal Basin; Bangladesh.International Journal of Earth Sciences.
MLA	Khanam F.,et al."Sedimentology and basin-fill history of the Cenozoic succession of the Sylhet Trough; Bengal Basin; Bangladesh".International Journal of Earth Sciences (2020).