青藏羌塘三叠纪盆地的形成与演化  

Formation and Evolution of Triassic Qiangtang Basin in Qinghai-Tibet Plateau

作　　者：郑孟林[1] 刘池阳[2] 王定一[2] 

机构地区：[1]石油大学盆地与油藏研究中心 [2]西北大学地质学系,陕西西安710069

出　　处：《新疆石油地质》2004年第1期13-16,共4页Xinjiang Petroleum Geology

摘　　要：羌塘三叠纪盆地的形成演化受拉竹龙-西金乌兰陆间裂谷和班公湖-丁青裂谷演化的控制,早中三叠世为三叠纪盆地初始形成阶段,沉积范围局限于今盆地西北部。晚三叠世早期,拉竹龙-西金乌兰陆间裂谷扩张,班公湖-丁青裂谷初始形成,盆地断陷沉降,发育三种类型的建造:碎屑岩建造,碳酸盐岩建造和中基性火山岩建造。晚三叠世中期,盆地处于构造相对稳定阶段,全区被海水淹没,沉积了一套厚度相对变化不大的海相碳酸盐岩。晚三叠世晚期,由于拉竹龙-西金乌兰陆间裂谷的闭合,盆地发生大规模海退,形成了一套砂泥岩夹煤层或煤线为主体的沉积建造。The formation and evolution of Triassic Qiangtang basin are contr ol led by Lazhulong-Xijinwulan rift and Bangonghu-Dingqing rift.In early and mid dle Triassic,the basin is at the beginning of the formation and the deposition is limited in northwestern part of it.In the early peri-od of late Triassic,t hese two rifts initiated shaping and by the basin's faulting and subsiding,thr ee formations are developed as clastic formation,carbonate formation and mediat e-basic volcanic formation.During the middle period of late Triassic,the basi n is in relative stable stage com-pletely submerged by sea water.In the late p eriod of late Triassic,Lzhulong-Xijinwulan rift is closed followed by large-s cale marine regressing,hence the depositional formation dominated by sand-shal e intercalated with coal seam or″coal line″is shaped.

关 键 词：三叠纪 火山岩 构造地质学 沉积学 

分 类 号：P54[天文地球—构造地质学] P588.14[天文地球—地质学]