郭晓玉^1,,
高锐^1,2,
高建荣³,
徐啸¹,
黄兴富¹
1. 中山大学地球科学与工程学院, 广州 510275
2. 中国地质科学院地质研究所, 北京 100037
3. 中国石油勘探开发研究院, 北京 100083

基金项目: 国家自然科学基金项目（41674087，41430213，41590863）资助


详细信息

作者简介: 郭晓玉, 女, 1979年生, 副教授, 主要从事地球物理数据的综合解释及相关构造建模.E-mail:xguo0515@126.com

中图分类号: P313;P315

收稿日期:2017-06-24
修回日期:2017-11-08
上线日期:2018-02-05

Integrated analysis on the tectonic features of the Maxian Shan fault zone in the northeastern Tibetan plateau

GUO XiaoYu^1,,
GAO Rui^1,2,
GAO JianRong³,
XU Xiao¹,
HUANG XingFu¹
1. School of Earth Sciences and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
2. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China
3. The Research Institute of Petroleum Exploration and Development, Beijing 100083, China


MSC: P313;P315

--> Received Date: 24 June 2017
Revised Date: 08 November 2017
Available Online: 05 February 2018


摘要
摘要:左旋走滑的马衔山断裂带位于青藏高原东北缘陇中盆地内部，呈北西-南东向伸展.宽约8~10 km，长约115 km.马衔山断裂带表面虽然局部已被黄土覆盖，但并不代表它的活动性不强.1125年的兰州M_S7.0地震就发生在马衔山断裂带北缘的西侧.前人对马衔山断裂带的研究基本上多依靠于地表地质和地球化学数据分析进行一般性讨论，而缺少对马衔山断裂带深部构造伸展的清晰认识.本文中，我们主要依靠一条横跨马衔山断裂带的深地震反射剖面数据资料进行地壳尺度的构造解释.在此基础之上，对研究区所获得的重力数据进行相应的处理分析.最后辅助于马衔山断裂带两侧野外地表形变的观察和前人研究所获得的地球化学数据分析，我们的研究认为马衔山断裂带为一不同块体间的边界断裂带.它可能形成于早古生代祁连造山带东缘北部马里亚纳式岛弧和南部日本式岛弧的相互拼贴作用.该边界断裂带在随后的青藏高原东北缘物质逃逸过程中被激活，并且目前仍处于构造活动活跃期.
关键词: 马衔山断裂带/
区域重力异常/
深地震反射剖面/
综合地球物理解释/
块体边界

Abstract:The sinistral strike-slip Maxian Shan fault zone is located within the interior of the north-easternmost Tibetan Plateau. It extends in northwest-southeast direction over a distance more than 115 km with widths 8~10 km. Although this fault zone is partly covered by widespread Quaternary losses, its tectonic activity is not necessarily low. One piece of evidence that the 1125 M_S7.0 Lanzhou earthquake took place just at the west of the north edge of the Maxian Shan fault zone. Previous studies are mostly concentrated on the surface expression of this fault zone and geochemical analysis of the plutons on its both sides to delineate its traces, lacking the information on its extension at depth. In this work, we employed a NE-SW striking 310 km-long deep seismic reflection profile that crosses the Maxian Shan fault zone to reveal its deep structure. In combination with processing and analysis of the available gravity anomalies and previous geochemical studies, we suggest that the Maxian Shan fault zone is a block boundary that separates two different paleo-volcanic arcs of the Qilian orogenic belt. It formed during the amalgamation of these two paleo-volcanic arcs in Early Paleozoic. The Maxian Shan fault zone was later reactivated during northeastward extrusion of the Tibetan Plateau and remains tectonically active now.
Key words:Maxian Shan fault zone/
Regional gravity anomaly/
Long deep seismic reflection profile/
Integrated analysis/
Block boundary



PDF全文下载地址:

http://www.geophy.cn/data/article/export-pdf?id=dqwlxb_14355