热带海洋学报 ›› 2016, Vol. 35 ›› Issue (5): 88-96.doi: 10.11978/2015138CSTR: 32234.14.2015138

• 海洋地球物理学 • 上一篇    下一篇

东沙西南海区泥火山的分布及其物质来源层位*

赵旭1, 2, 阎贫1, 王彦林1, 郑红波1   

  1. 1. 中国科学院南海海洋研究所, 中国科学院边缘海地质重点实验室, 广东 广州 510301;; 2. 中国科学院大学, 北京 100049
  • 收稿日期:2015-11-12 出版日期:2016-08-29 发布日期:2016-09-22
  • 作者简介:赵旭(1990—), 男, 山东省聊城市人, 硕士生, 从事海洋地质和海洋地球物理研究。E-mail: zhaoxu@scsio.ac.cn
  • 基金资助:
    基金项目:国家自然科学基金资助项目(41376062、91328205、41349908); 海洋地质保障工程项目(GZH20110205)

The distribution and provenance strata of mud volcanoes in the waters southwest of the Dongsha Islands

ZHAO Xu1, 2, YAN Pin1, WANG Yanlin1, ZHENG Hongbo1   

  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 Sciences, Beijing 100049, China
  • Received:2015-11-12 Online:2016-08-29 Published:2016-09-22
  • Supported by:
    Foundation item: Supported by the National Natural Science Foundation of China (41376062, 91328205, 41349908); Security Project of Marine Geology (GHZ20110205)

摘要: 早期的多道地震和浅剖测线数据表明东沙西南海域可能存在一些泥火山。2014年在该海域加密了多道地震测线和浅剖测线。通过对新采数据的处理, 在多道地震剖面中发现了大量反映泥火山存在的丘形隆起、喷发凹槽及反射空白带等特征; 在浅剖剖面上发现了指示泥火山存在的丘状构造、局部海底反射加强以及气体羽等现象。对比分析相邻的多道和浅剖剖面, 发现该区存在大量泥火山, 沿NWW—SEE方向呈带状分布。其中最大泥火山长度大于15km, 宽约8km, 高约285m。泥火山坡度较大, 两翼倾角在5.5°~15.9°之间。剖面上显示有些泥火山对应的构造形变及反射空白带至少延伸到海底以下5.5km深度, 经过与附近海区地震剖面解释成果的对比, 推断泥火山物质来源层位为中生界。

关键词: 东沙西南, 泥火山, 多道地震, 浅剖, 中生界

Abstract: A few mud volcanoes were found in the Dongsha waters according to reconnaissance multi-channel seismic (MCS) and Chirp sub-bottom profiles. Denser MCS and sub-bottom survey lines were run in the area in 2014. Blanking zones under submarine mounds and rimmed depression were revealed by the MCS section, while locally enhanced seafloor reflection and gas plumes, by Chirp sub-bottom data. Correlation of MCS profiles and sub-bottom profiles shows these mud volcanoes sit in the NWW-SEE. The largest mud volcano there is ~15 km long, ~8 km wide, and ~285 m high. The steep slopes of mud volcanoes ranged from 5.5° to 15.9°. Correlated with the interpreted MCS profiles nearby, the provenance strata of some mud volcanoes there is of Mesozoic, considering that the tectonic deformation and reflection blanking zone under mud volcanoes extends at least 5.5 km below seafloor.

Key words: southwest of the Dongsha Islands, mud volcano, multi-channel seismic, sub-bottom profile, Mesozoic