塔里木盆地三叠-侏罗纪沉积相与构造关系

1985年 6卷 第No.4期
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THE TRIASSIC-JURASSIC SEDIMENTARY FACIES OF TARIM BASIN IN RELATION TO TECTONICS
高兴辰
Gao Xingchen
本区三叠-侏罗系主要出露于天山、昆仑山、阿尔金山山前地带,以及塔东和孔雀河斜坡地区,为一套潮湿气候的含煤碎屑岩沉积。可分为洪积、冲积平原、三角洲、扇-三角洲以及湖泊等相(图1)。
Studies show that the ancient tectonic environment controlled not only the formation and development of Tarim Basin,but also imposed apparent influ-ence on various typical lithofacies of Triassic-Jurassic sediments,for example,the Baicheng and Xinan half-graben depressions,are characterized by narrowlitho facies near the steep escarpments and wide spread lithofacies in shallowslopes;the Tadong downwarping depression is characterized usually by con-centric distribution of lithofacies;while the Minfeng-Jianggesha fault-troughis characterized by symmetrical distribution of lithofacies.On the steeply down-warped side of the half-graben,sediments are predominated by arenaceous-conglomeratic,proluvial and fan-deltaic facies,while on the shallow slope side,they are mainly deltaic,alluvial and shallow water lacustrine facies.Sediments of the fault-trough depression are represented by proluvial and fan-deltaic facies with great number of arenaceous-conglomeratic materials on both sides nearescarpments.Sediments in downwarped region are composed of fine-grained clastics with wide spread deltaic and alluvial facies and a large area of deepwater depocenter.Stratigraphic traps can probably be found in the outer marginof a deltaic structure and tributary channel in the domain of the downwarping region.Traps relative to the proluvial fan-delta might be characterized by fault trough.Whereas in the steeply warped side of the halfgraben,the stratigraphic traps might be discoverd within fan-deltaic and turbidity sediments;while in the gentle slope,traps can mainly develop in the tapering updip sandstones.
10.11743/ogg19850404