摘要
江达弧内盆地位于西藏东部 ,现今被厚约 10 0 0 0m的三叠系所覆盖 ,三叠纪时该区以海相沉积为主 ,并以巨厚浊积岩与频繁火山活动形成的钙碱性系列弧火山岩为特征。在露头剖面上 ,识别出 10个三级层序。这些层序共经历了 37Ma的时间演化 ,估算每个层序平均所占时限为 3 7Ma。研究认为层序形成的主控因素应是构造—火山、沉积物补给与海平面升降三者之间相互作用过程的响应 ,其中构造与弧火山作用起决定作用。
Jamda intra-arc basin is located in east Xizang and is filled in the triassic with a thickness of about 10*!000 m.The Triassic is characterized by marine sediments with tremendous turbidite and calc-alkaline arc volcanic suite.10 third-order sequences are recognized in outcrop area.These sequences were developed during 37 Ma,and average time for a sequence is estimated at 3.7 Ma.This study shows that the sequence stratigraphy is controlled mainly by tectono-volcanism,sediment supply and eustasy,but tectono-volcanism is decisive factor.
出处
《四川地质学报》
2001年第1期16-19,共4页
Acta Geologica Sichuan
基金
国家自然基金!项目 (4996 2 0 0 1)
国土资源部"九五"攻关项目! (95 0 2 0 0 10 1)联合资助
