热带海洋学报 ›› 2014, Vol. 33 ›› Issue (1): 62-68.doi: 10.11978/j.issn.1009-5470.2014.01.008

• 海洋地质学 • 上一篇    下一篇

南海北部白云凹陷及其邻区的岩石圈强度分析*

吴保珍1, 2, 施小斌1, 杨小秋1, 石红才1, 2, 蒋海燕3, 杨军1, 2   

  1. 1.中国科学院边缘海地质重点实验室, 中国科学院南海海洋研究所, 广东 广州 510301; 2.中国科学院大学, 北京100049; 3. 广东省核工业地质局二九三大队, 广东 广州 510800
  • 收稿日期:2012-12-17 修回日期:2013-01-30 出版日期:2014-03-07 发布日期:2014-03-08
  • 作者简介:吴保珍(1986~), 男, 江苏省徐州市人, 在读研究生, 从事海洋岩石圈有效弹性厚度研究。E-mail: ww_bbzz@163.com
  • 基金资助:
    国家自然科学基金(41176050); 文中部分图件使用Wessel et al(1995)编制的GMT软件绘制。

Analysis on lithospheric strength of the Baiyun Sag and its surrounding area in the northern margin of the South China Sea

WU Bao-zhen1, 2, SHI Xiao-bin1, YANG Xiao-qiu1, SHI Hong-cai1, 2, JIANG Hai-yan3, YANG Jun1, 2   

  1. 1. Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; 2. University of Chinese Academy of Science, Beijing 100049, China; 3. 293 Geological Team of Guangdong Province Nuclear Industry Geological Bureau, Guangzhou 510800, China
  • Received:2012-12-17 Revised:2013-01-30 Online:2014-03-07 Published:2014-03-08

摘要: 选取纵穿南海北部陆缘的长排列多道地震剖面, 利用挠曲回剥和重力异常模拟相结合的过程导向法(process-oriented gravity modelling, POGM), 计算了研究区内不同构造单元同张裂及裂后阶段的岩石圈有效弹性厚度(effective elastic thickness, Te), 并对其分布特征进行了详细分析。计算结果显示: 张裂过程中岩石圈强度很弱; 而裂后阶段岩石圈强度在不同构造单元并不相同, 其中番禺低隆起和下陆坡区强度较高, Te约为15km, 而在北部坳陷带为7km左右, 白云凹陷地区强度最低, 仅为5km左右。获得的岩石圈强度结果,加深了对南海北部大陆边缘盆地特征和岩石圈构造演化过程的认识, 具有重要的意义。

Abstract: Using flexural backstripping and gravity anomaly modeling techniques and Process-Oriented Gravity Modelling (POGM), we calculated variable effective elastic thickness (Te) of a long cable, multi-channel seismic reflection profile across the northern margin of the South China Sea and analyzed the lithospheric strength distribution during rifting and post rifting. Results show that the lithospheric strength is weak during rifting and that the post-rifting Te is different for different tectonic units. The lithospheric strengths of the Panyu Low Rise and Lower Slope are larger, with Te of about 15 km; the Te of the Northern Depression is about 7 km, and the Baiyun Sag is the weakest in strength, whose Te is only about 5 km. Lithospheric strength can help to understand the distribution of the basin and the process of lithospheric evolution in the northern continental margin of the South China Sea.

中图分类号: 

  • P736.12