欢迎访问现代地质!

现代地质 ›› 2005, Vol. 19 ›› Issue (1): 1-13.

• 天然气水合物沉积学特征 •    下一篇

南海陆坡中新世以来沉积物特性与气体水合物分布初探

苏新1. 陈芳2. 于兴河1. 黄永样2   

  1. 1 中国地质大学 海洋学院,北京100083; 2 广州海洋地质调查局,广东 广州510760
  • 收稿日期:2004-11-20 修回日期:2004-12-25 出版日期:2005-01-20 发布日期:2005-01-20
  • 作者简介:苏新, 女,教授,1957年出生, 地层古生物学专业, 主要从事钙质超微化石和海洋地质的研究工作。
  • 基金资助:

    科技部重点基础研究发展规划项目(G2000046705)。

A Pilot Study on Miocene through Holocene Sediments  from the Continental Slope of the South China Sea in Correlation with Possible Distribution of Gas Hydrates

SU Xin1, CHEN Fang2, YU Xing-he1, HUANG Yong-yang2   

  1. 1 School of Marine Geosciences, China University of Geosciences, Beijing100083,China;
    2 Guangzhou Marine Geological Survey, Guangzhou,Guangdong510760,China
  • Received:2004-11-20 Revised:2004-12-25 Online:2005-01-20 Published:2005-01-20

摘要:

通过对南海陆坡地区中新世以来沉积物的一些属性和特征的研究,获得了下面的初步认识:(1)南海陆坡有几个沉积速率较高的地区, 如东沙一带、西沙海槽、中建南地区,以及南沙西南部和西北部(曾母、万安盆地);(2)大洋钻探钻井资料的研究表明,中新世与早上新世为高碳酸盐比值的低速堆积期,而近200万a以来为低碳酸盐比值的高速堆积期,上新世晚期至全新世沉积物以粘土质粉砂和粉砂质粘土为最主要成分;(3)南海不同时期的沉积速率不同,全新世为沉积速率最高的时期,其次为更新世;上新世和中新世为沉积速率较低的时期。南海利于气体水合物存藏的沉积可能为全新世和更新世的沉积;(4)对南海晚第四纪以来沉积物的综合研究表明南海陆坡的A区(东沙附近)、B区(西沙海槽)、D区(南海西部、越南以东)等地区可能利于气体水合物的形成和分布;而E区(南沙西南部)、F区(南沙中上部)和G区(南沙海槽)则是气体水合物调查值得关注的地区。

关键词: 气体水合物, 沉积物属性, 沉积组分, 南海陆坡, 中新世, ODP 184航次

Abstract:

A pilot study on Miocene through Holocene sediments throughout the continental slope of the South China Sea was carried out for evaluating possible sediment regions and layers which might be suitable for distribution of gas hydrates. Among the Miocene through Holocene sediment sequences, the highest sedimentation rates were seen from the Holocene sediments, the second record occured during the Pleistocene. This result suggests Pleistocene and Holocene sediments might be  better host for gas hydrates than sediments formed during other periods in the South China Sea.Four areas (Dongsha area, Xisha Trough, Zhongjiannan area and Nansha area) with high sedimentation rates were recognized, especially sediments from the first three areas are rich of organic carbon and contain a number of autogenetic minerals associated with gas hydrates in sediments.These sediment records imply that Dongsha area, Xisha Trough and Zhongjiannan area are of possible importance for exploration of gas hydrates.

Key words: gas hydrate, feature of sediment, sedimentary composition, the continental slope of the South China Sea, Miocene, ODP Leg 184

中图分类号: