古地理学报2024，Vol.26Issue(4)：926-940,15.DOI:10.7605/gdlxb.2024.03.052
早始新世温室气候与海侵作用对库车坳陷库姆格列木群含盐层系沉积的协同控制作用
Collaborative controls of the Early-Eocene greenhouse climates and transgression on deposition of salt-bearing sequence of Kumugeliemu Group in Kuqa Depression
摘要
Abstract
The thick salt-bearing sequence in Paleogene Kumugeliemu Group(54-46 Ma)of the Kuqa Depression acts as the high-quality regional caps for oil and gas accumulation.However,the original temporal-spatial distribution,palaeogeographic environment,and sedimentary controlling factors of the salt-bearing sequence remain unclear,which causes great difficulties for the drilling of the subsalt hydro-carbon reservoirs.Through the outcrop measurement at the basin margin and the logging element analysis within the basin,the correlation of sedimentary cycles between the lake-basin center and the margin was carried out to explore the main controlling factors of the salt-bearing sequence deposition of Kumugeliemu Group.The Kumugeliemu Group consists of three third-order cycles.The first third-order cycle Ⅰ 1 is char-acterized by the lithofacies assemblage of conglomerates,sandstones,mudstones and gypsums at basin margins,and of mudstones,gypsums,halites,carbonates at basin center,indicating an palaeogeo-graphic-environment transformation from a terrigenous basin to a continental-margin basin.The second third-order cycle Ⅰ 2 is characterized by the lithofacies assemblage of conglomerates,sandstones,mud-stones,and gypsums at basin margins and the assemblage of thick halites and minor mudstones at basin center,corresponding to a depositional model of a terrigenous epeiric basin.The third third-order cycleⅠ 3 has similar lithofacies assemblage at the lake-basin margin and center,characterized by thin layer gyp-seous mudstones and mudstones,typical depositional model of terrigenous playa lakes.Combined with the Early-Eocene global climates and sea-level changes,it is believed that the deposition of thick gypsum rocks of Ⅰ 1(ca.54-51 Ma)were related to the Early Eocene Climatic Optimum(53-51 Ma)and global sea-level rise.The deposition of thick halite rocks in Ⅰ 2(ca.51-48 Ma)was controlled by the global dry climate and sea-level rise.The absence of thick salt-bearing sequence deposits in Ⅰ 3(ca.48-46 Ma)is related to the global dry climate and sea-level drops.关键词
含盐层系/物质来源/陆缘盆地/沉积旋回/库姆格列木群/库车坳陷/塔里木盆地Key words
salt-bearing sequence/salt sources/epeiric basin/sedimentary cycle/Kumugeliemu Group/Kuqa Depression/Tarim basin分类
天文与地球科学引用本文复制引用
张锡婷,范坤宇,郭佩,李鹏真,苗如霖,邓宾..早始新世温室气候与海侵作用对库车坳陷库姆格列木群含盐层系沉积的协同控制作用[J].古地理学报,2024,26(4):926-940,15.基金项目
国家自然科学基金项目(编号:42272117,42002116)资助.[Financially supported by the National Natural Science Foundation of China(Nos.42272117,42002116)] （编号:42272117,42002116）
