南海区域断裂特征及其基底构造格局
Characteristic of regional fractures in South China Sea and its basement tectonic framework
鲁宝亮 1王璞珺 2张功成 3王万银4
作者信息
- 1. 长安大学地质工程与测绘学院长安大学重磁方法技术研究所,西安710054;吉林大学地球科学学院,长春 130061
- 2. 吉林大学地球科学学院,长春 130061
- 3. 中海油研究总院,北京 100027
- 4. 长安大学地质工程与测绘学院长安大学重磁方法技术研究所,西安710054
- 折叠
摘要
基于覆盖南海的水深、重力、磁力以及地震资料,结合区域地层特征,通过地质与地球物理综合解释研究,明确了南海区域断裂和前新生代基底构造格局特征.古生代以来,受控于特提斯和太平洋两大构造域影响,导致南海地区板块汇聚与分离,不同时期南海构造应力环境各异,形成了性质不同的四周陆缘,致使北部陆缘主要为拉张型断裂,南部陆缘为挤压型断裂,西部陆缘为走滑型断裂,而东部陆缘则为海沟俯冲型断裂,以NE-NEE向、NW向和近SN向3组走向为主.在此研究基础上,海陆综合考虑,结合地块构造层序列、沉积建造、变质作用以及构造演化历史,以地块拼接带(蛇绿岩带、蛇绿混杂岩带及扩张边缘带)作为二级构造单元的分界线,以主要走滑断裂作为三级构造单元的分界线,将南海及其围区划分为8个二级构造单元以及9个三级构造单元.南海地区基底构造单元具有不同的构造层,沉积建造以及变质作用,显示出不同时期具有不同的构造属性.本文的研究结果将有助于进一步了解南海地区基底构造格局以及揭示前新生代构造演化过程,为该区新生代构造演变提供基底制约.
Abstract
Based on water depth,gravity,magnetic and seismic data covering the South China Sea,and combined with regional stratigraphic features,the regional faults and basement tectonic framework were studied by integrated interpretation of geology and geophysics.From Paleozoic,South China Sea areas were controlled by Tethys and Pacific tectonic domains,which led to convergence and separation of the blocks.Therefor,the tectonic stress environment were varied in different periods,and formed different properties of continental margin of South China Sea.The faults strike are major in NE-NNE-,NW-and near SN-trending,the northern margin mainly extensional fractures,the southern margin mainly extrusion fractures,and the western margin mainly strike-slip fractures,while the eastern margin compared with subduction-type fractures.And,on the basis of regional faults,tectonic features,sedimentary,metamorphic formation and evolution history,and considering the land and sea geology,the South China Sea basement is divided into eight secondary tectonic units limited by suture line and expansion of the edge faults,and nine third-level tectonic units limited by the main strike-slip faults.South China Sea basement tectonic units have different structural layers,sedimentary and metamorphic,showing different times with different structural properties.The results will contribute to a better understanding of the tectonic framework of the South China Sea,as well as reveal pre-Cenozoic tectonic evolution,and providing basement constraints for the Cenozoic tectonic evolution.
关键词
南海/区域断裂/基底/构造单元/重磁异常Key words
South China Sea/regional fracture/basement/tectonic framework/gravity and magnetic anomaly引用本文复制引用
基金项目
国家科技重大专项(2011ZX05025)
中央高校基本科研业务费专项资金(2014G3262010)
中央高校基本科研业务费专项资金(310826151052)
出版年
2015
NETL
NSTL
维普
万方数据