地质学报2017，Vol.91Issue(3)：588-604,17.
塔里木盆地新元古代裂谷盆地层序样式
The Style of Sequence Stratigraphy of Neoproterozoic Rift Basin in the Tarim Basin
摘要
Abstract
With the breakup of Rodinia in Neoproterozoic,some rift basins formed aroud or in the Tarim basin,which was a small plate in Rodinia.By studying the evolution of rift basin and stratum,sedimentary,we can know the breakup process of Rodinia.According to the theory of basin dynamics,sequence stratigraphy and sedimentology,unconformity surface,sequence stratigraphy and sedimentary facies are analyzed with outcrop,well,seismic data,and the evolution and cause of rifting basin are further studied,and the differences of the evolution of rifting between Tarim Basin and Yangtze Basin are studied.The Nanhua and Cathay is the first grade sequence,limited by the unconformity of Td (between the Nanhua and basement) and T1 (between the cambrian and Cathay).Td,acting as the stratum on metamorphosed basement,resulted from the Tarim movement which represents the continental break-up of Rodinia in the Early to Middle Neoproterozoic.And T1 was caused by the vertical lift of Keping movement in Tarim.By the evolution of rift basin,there are three stages,namely rapid chasmic stage,steady subsidence stage and the rift valley shrinking period,respectively corresponding to three second-order sequences.In the rapid chasmic stage (SQ1),there are many small rift basins of horst and graben,the main facies include shore shelf,fluvial facies and delta facies,with water depth increasing.In the steady subsidence stage (SQ2),good connectivity of the basin strengthens resulted in the formation a unified basin with shoreline facies,delta facies,shallow shelf facies,and basin facies.In the rift valley shrinking period (SQ3),fault activity weakened due to the mantle plume cooling and crustal rebound,and the strata rose and onlap on the uplift,by which the carbonates deposit surrounding the basin.Controlled by the sea level change,glaciations and climate,there are 13 three-order sequences including a special sequence composing of titles and capcarbontate in the glacial epoch.The Marinoan glacial epoch was a worldwide event,corresponding to tillite of the Nantuo Formation and cap-carbonate in Doushantuo Formation.However,the siltstone of the Iamotike Formation in the Quruqtagh area of Tarim basin,which is on top of tillite of the Teruiaiken Formation,did not develop cap-carbonitic later.This is related to the evolution of rift systern,the cover of Tarim Formed rock 70Ma.After the deposition of tillite,the water deepened fast.Meanwhile there were clastic stones to supply,which restrained the growth of carbonate.The study of Rodina evolution is of great importance for understanding of Neoproterozoic structural and sedimentary environment,source rocks and reservoirs.A comparison with the responses of break-up of Rodinia among different rifting basins is worth further research.关键词
新元古代/南华—震旦系/雪球事件/Rodinia大陆/裂谷盆地Key words
Neoproterozoic/Nanhua-Cathay/the snowball Earth/Rodiniasupercontinent/rifting basin引用本文复制引用
姜海健,陈强路,杨鑫,储呈林..塔里木盆地新元古代裂谷盆地层序样式[J].地质学报,2017,91(3):588-604,17.基金项目
本文为中石化油田部项目(2011ZX05005-002-001)和中石化科技部项目(P10023)资助的成果. （2011ZX05005-002-001）
