青藏高原新生代南北走向裂谷研究进展  

Research Progress in Cenozoic N-S Striking Rifts in Tibetan Plateau

作　　者：张佳伟 李汉敖 张会平[1] 徐心悦 Zhang Jiawei;Li Han'ao;Zhang Huiping;Xu Xinyue(State Key Laboratory of Earthquake Dynamics,Institute of Geology,China Earthquake Administration,Beijing 100029,China;State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]中国地震局地质研究所地震动力学国家重点实验室,北京100029 [2]中国地质大学(北京)生物地质与环境地质国家重点实验室,北京100083

出　　处：《地球科学进展》2020年第8期848-862,共15页Advances in Earth Science

基　　金：第二次青藏高原综合科学考察研究项目“碰撞以来古地理格局与构造地貌过程”(编号:2019QZKK0704);国家自然科学基金项目“西藏冈底斯山弧高海拔古地貌开始形成时间”(编号:41902121)资助.

摘　　要：青藏高原新生代南北走向裂谷的形成是印度—欧亚大陆碰撞后持续挤压造山的重要产物,其形成和演化对于理解青藏高原的生长具有重要意义。近年来,运用地质年代学、构造地质学、岩石地球化学和地球物理探测等手段对南北走向裂谷的启动时间、形成机制和演化过程进行了深入研究,但对于青藏高原南北走向裂谷的认识仍难以达成共识。对近年来青藏高原南北走向裂谷的拉张时间、形成机制及其与高原深部圈层的关系等方面的研究现状和存在问题进行了综述:南北走向裂谷主要拉张时期为中新世;其成因复杂,不同时期可能受控于不同机制;南北走向裂谷与高原内部钾质、超钾质岩具有密切成因联系,其分布特征可能受高导低速体影响。基于现有认识,更精确的年代学约束、深部过程探测以及数值模拟是今后南北走向裂谷研究的发展趋势。The formation of the Cenozoic N-S striking rifts in the Tibetan Plateau is the consequence of continuous contraction after the India-Asia collision.Its formation and evolution are of great significance for understanding the growth of the Tibetan Plateau.In recent years,geochronology,structural geology,geochemistry and geophysical exploration have been used to study the onset timing,mechanism and evolution process of the N-S striking rifts,and the N-S striking rifts are related to the deep dynamics in Tibet.However,it is still difficult to reach a consensus on the understanding of the N-S striking rifts in the Tibetan Plateau.This paper summarized the research status and existing problems on the onset timing,mechanism and their relationship with the deep layer of the plateau:the main extension period of the N-S striking rifts is Miocene;mechanisms controlling its formation are complex and may be various in different periods;the N-S striking rifts have a close genetic relationship with potassium and ultrapotassic rocks in the plateau,and their distribution may be affected by high-conductivity and low-velocity bodies.Based on existing knowledge,more precise geochronological constraints,deep process detection,and numerical modeling will be the future development trends in the study of N-S striking rifts.

关 键 词：南北走向裂谷 高原隆升 启动时间 深部动力学 

分 类 号：P542[天文地球—构造地质学]