松潘—甘孜地块地壳性质再研究  

Research of the crustal property of the Songpan-Garze block

作　　者：王海燕[1] 高锐[1] 张季生[1] 李秋生[1] 管烨[1] 李文辉[1] 郭晓玉[1] 李洪强[1] 

机构地区：[1]中国地质科学院地质研究所,大陆构造与动力学国家重点实验室,国土资源部深部探测与地球动力学重点实验室,北京100037

出　　处：《地质科学》2016年第1期41-52,共12页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家专项“深部探测技术实验与集成”（编号：SinoProbe-02-01,SinoProbe-08-02）,国家自然科学基金项目（编号：41430213,41274097,40874045）和中国地质调查局工作项目（编号：1212011220260）资助.致谢 本文得到洪大卫研究员的指导和帮助,在此表示衷心的感谢.

摘　　要：松潘—甘孜地块的基底构造性质对于探讨青藏高原的形成至关重要，备受国内外学者的关注。然而，由于松潘—甘孜地块被广泛分布的三叠纪复理石沉积所覆盖，关于松潘—甘孜地块基底属性的研究并不多见，它属于洋壳还是陆壳，至今仍在争论之中。本文利用跨越松潘—甘孜地块的深地震反射剖面、深地震测深剖面、区域航磁异常和花岗岩同位素地球化学等资料，通过综合分析研究其地球物理与地球化学特征，发现松潘—甘孜地块的下地壳存在元古代变质基底，该基底具有亲扬子地块的性质。The Songpan-Garze block, located in the northeastern part of the Tibetan Plateau, occupies an elongate triangular area between East Kunlun-West Qinling orogenic, the Qiangtang terrane, and Longmen Shan fault zone. Its basement structural property is very important for discussing the formation of the Plateau, and has attracted many attentions of the domestic and foreign scholars. However, due to the Songpan-Garze block is characterized by a thick Triassic flysch sequence commonly, study of its basement nature are rare. The Songpan- Garze basement is still controversy on oceanic or continental crust. Therefore, based on a synthesis that includes reflective seismic profile, deep seismic sounding profile, regional aeromagnetic anomaly data, and granitoid isotopic data, we suggest that the Songpan-Garze block might exhibit the characteristics of a continental craton. Moreover, we infer that the Proterozoic metamorphic basement of the Songpan-Garze block might have a property with that of the Yangtze block.

关 键 词：基底属性 深反射剖面 航磁异常 花岗岩同位素年龄 

分 类 号：P313.2[天文地球—固体地球物理学]