西藏羌塘盆地抬升冷却历史及意义  

Uplift and cooling history of Qiangtang Basin and its significance

作　　者：任战利[1,2] 崔军平[1,2] 刘池洋[1,2] 李铁军[3] 陈刚[1,2] 陈占军[2] 祁凯[2] 豆霜[2] 

机构地区：[1]西北大学大陆动力学国家重点实验室,西安710069 [2]西北大学地质学系,西安710069 [3]中国石化科技开发部,北京100728

出　　处：《石油实验地质》2016年第1期15-22,31,共9页Petroleum Geology & Experiment

基　　金：国家自然科学基金(41372128);国家重大专项(2011ZX05005-004-007HZ)资助

摘　　要：以地质构造背景及热演化程度为约束,运用磷灰石裂变径迹分析方法,对羌塘盆地进行了低温热年代学研究。羌塘盆地记录的抬升冷却年龄可划分为2大阶段：第一阶段主要为早白垩世晚期—晚白垩世（108.7～69.8 Ma）;第二阶段主要为始新世中、晚期—中新世晚期（44.4～10.3 Ma）。第一阶段抬升冷却年龄是班公湖—怒江洋关闭后进一步会聚挤压造成羌塘盆地中央隆起地层抬升冷却的记录。第二阶段抬升冷却年龄可进一步划分为3期,分别对应44.4～30.8,26.1～22.6,10.3 Ma,其中渐新世晚期—中新世早期（26.1～22.6 Ma）为主隆升期。第二阶段抬升冷却年龄反映了印度板块与欧亚板块碰撞及之后强烈挤压造成羌塘盆地抬升冷却过程。磷灰石裂变径迹方法确定的羌塘盆地抬升冷却年龄表明,青藏高原在44.4 Ma开始挤压隆升,在26.1～22.6 Ma青藏高原大规模整体隆升,青藏高原形成,在中新世晚期（10.3 Ma）以来青藏高原继续挤压隆升。The low temperature thermochronology of the Qiangtang Basin was studied by the apatite fission track method based on tectonic and thermal evolution. The uplift and cooling ages recorded in the Qiangtang Basin could be divided into two phases： the first one mainly happened from the late Early Cretaceous to the Late Cretaceous （108.7 to 69.8 Ma） and the second one mainly 10.3 Ma）. The first phase is an uplift and cooling was caused by the compression of the closing of the from the Middle-Late Eocene to the Late Miocene （44.4 to record of the central uplift belt in the Qiangtang Basin, which Bangong-Nujiang oceans. The second phase can be further di- vided into three times： 44.4-30.8, 26.1-22.6, and 10.3 Ma, among which the Late Oligocene to Early Miocene （26.1-22.6 Ma） is the main uplift period. The second phase is an uplift and cooling record that was caused by the compression due to the collision of the Indian and Eurasian plates. The apatite fission track method was used to determine the uplift and cooling ages of the basin. The Qinghai-Tibet Plateau began to uplift at 44.4 Ma, and an overall strong uplift took place during 26.1-22.3 Ma. The plateau was formed after the strong uplift, and has continued to uplift since the Late Plioeene （10.3 Ma）.

关 键 词：裂变径迹 退火带 冷却带 抬升冷却 羌塘盆地 青藏高原 

分 类 号：TE121.11[石油与天然气工程—油气勘探]