羌塘盆地东缘中侏罗统布曲组碳酸盐岩成岩作用与成岩环境  

Diagenesis and diagenetic environments of the carbonate rocks from the Middle Jurassic Buqu Formation in the eastern Qiangtang Basin on the Qinghai-Xizang Plateau

作　　者：马伯永[1,2] 王根厚[1] 李尚林[3] 段俊梅[3] 徐红燕[2] 

机构地区：[1]中国地质大学地球科学与资源学院,北京100083 [2]中国地质图书馆,北京100083 [3]中国地质调查局西安地质调查中心,陕西西安710054

出　　处：《沉积与特提斯地质》2010年第2期11-18,共8页Sedimentary Geology and Tethyan Geology

基　　金：中国地质调查局青藏高原1:25万仓来拉幅(I46C004003)区域调查项目;国家自然科学基金项目(批准号:40172014)

摘　　要：羌塘盆地东缘布曲组碳酸盐岩的成岩作用类型主要有泥晶化作用、胶结作用、压实压溶作用、破裂作用、溶解作用等,其中以破裂作用、溶解作用和泥晶化作用最为发育。根据成岩组构可将碳酸盐岩的成岩环境分为海水、大气淡水和埋藏三种成岩环境。初步总结了布曲组剖面上成岩作用与沉积环境和海平面变化的关系。沉积旋回的下部以选择性的内溶孔和海底泥晶化作用为主要特征,中上部以发育压实、压溶的埋藏成岩作用为主。海平面到达最高点以后快速下降,以发育晚期的大汽淡水溶蚀作用为主要特征。初步总结了海进环境下成岩作用演化序列;探讨了羌塘盆地东缘的布曲组在油气普查与方面的重要意义。The diagenesis types of the carbonate rocks from the Middle Jurassic Buqu Formation in the eastern Qiangtang Basin on the Qinghai-Xizang Plateau consist of micritization,cementation,compaction-pressure solution,fragmentation and dissolution,of which fragmentation,dissolution and micritization are more common than the others.Judged from diagenetic fabrics,the diagenetic environments comprise the sea water,meteoric and burial environments.The lower part of the depositional cycle II in the Buqu Formation is characterized by intragranular solution openings and submarine micritization,while the compaction-pressure solution in the burial diagenesis predominate in the middle and upper parts.The late meteoric dissolution occurs in response to the rapid falling of sea level following the maximum sea-level rise.The results of research in this paper show that the eastern Qiangtang Basin should be selected as the key prospective area for oil exploration.

关 键 词：羌塘盆地 布曲组 碳酸盐岩 成岩作用 成岩环境 

分 类 号：P588.2[天文地球—岩石学]