雅鲁藏布江缝合带的双陆内俯冲构造与部分熔融层特征──INDEPTH项目结果的初步综合  

DOUBLE INTRACONTINENTAL UNDERUSTING STRUCTURE OF THE YARLUNG ZANGBO SUTURE AND DIFFERENT MOLTEN LAYERS──A COMPREIIENSIVE STUDY OF INDEPTH'S RESULTS

作　　者：赵文津[1] K.D.Nelson 徐中信[1] L.D.Brown J.T.Kuo R.Meissner 熊嘉育[1] INDEPTH项目组 

机构地区：[1]中国地质科学院,北京100037 [2]DepartmentofEarthScience,SyracuseUniversity,Syracuse, [3]InstitutefortheStudyoftheContinents,CornedUniversity,Ithaca, [4]LalnontDoMrtyGeologicalObservatory,Palisades, [5]InstitutfurGeophysik,Christian-Albrechts-UniversitaetzuKiel,

出　　处：《地球物理学报》1997年第3期325-336,共12页Chinese Journal of Geophysics

基　　金：中国国家科学技术委员会;中国自然科学基金资助;中国地质矿产部资助;美国国家科学基金会资助

摘　　要：根据中、美两国合作开展的西藏深反射地震结果,提出雅鲁藏布江缝合带（YZS）的"双陆内俯冲"构造模式和缝合带南、北分别存在着不同特征的、规模不一的部分熔融层；提出YZS处断裂向深部延深有限,认为YZS处地壳增厚有4种机制：①地壳规模的大的俯冲增厚；②上部地壳内的俯冲和背冲增厚；③下地壳内的底部垫托增厚和挤压增厚；④深部熔融体的向上挤入而引起的地壳增厚.提出可能存在两条大的伸展性断裂,造成江孜南、北地块间出现了大升降.The paper suggests a "Double Intracontinental Underthrusting Structure" modelwithin the Yarlung Zangbo Suture along with a deep architecture that there is a sepa-rate partial melting mass occurred 0n both southern and n0rthern sides of the suture,respectively, with their genetic origins being different one from another. The faultswithin the YZS have liAnted extensions t0 the depth' Here altogether four mechanisms of crustal thickening are suggested: 1) a thickening due to crust-scaleunderthrusting; 2) a thjckening within the upper crust due to underthrustingand backthrusting; 3) a thickehing within the lower crust due to bottom uplifting from belowand compression; 4) a thickening due to an upward intrusion of deep molten mass. Itis, therefor, inferred that there is a likelihood of ekistence of two big extension faults,resulting in great elevation and subsidence.

关 键 词：雅鲁藏布江 双陆内俯冲 熔融层 俯冲构造 

分 类 号：P542.3[天文地球—构造地质学]