阿拉伯海北部莫克兰增生楔天然气水合物浅表层识别标志  

Shallow and submarine identifications of gas hydrate in the Makran accretionary prism,northern Arabian Sea

作　　者：张振 邓希光[1,2] 姚会强 于淼[1,2] 王海峰 萧惠中[1,2] 程园 ZHANG Zhen;DENG Xiguang;YAO Huiqiang;YU Miao;WANG Haifeng;XIAO Huizhong;CHENG Yuan(Key Laboratory of Marine Mineral Resources,Ministry of Natural Resources/Guangzhou Marine Geological Survey,China Geological Survey,Guangzhou 510075,Guangdong,China;National Engineering Research Center for Gas Hydrate Exploration and Development,Guangzhou 510075,Guangdong,China)

机构地区：[1]自然资源部海底矿产资源重点实验室/中国地质调查局广州海洋地质调查局,广东广州510075 [2]天然气水合物勘查开发国家工程研究中心,广东广州510075

出　　处：《地质通报》2023年第1期27-40,共14页Geological Bulletin of China

基　　金：中国地质调查局项目《阿拉伯海天然气水合物资源探查》(编号:DD20190582);《***重点海域战略性矿产资源评价》(编号:DD20191009);南方海洋科学与工程广东省实验室(广州)人才团队引进重大专项《西太平洋富稀土沉积物;富钴结核成矿机制及其时空关系研究》(编号:GML2019ZD0106)。

摘　　要：阿拉伯海北部的莫克兰增生楔是阿拉伯板块以低速、低角度俯冲到欧亚板块之下形成的主动陆缘构造,蕴藏着丰富的天然气水合物资源。依据2019年中国在莫克兰增生楔海域采集的高分辨率多道地震资料、浅地层剖面及多波束测深数据,并结合以往的调查成果,探讨莫克兰海域天然气水合物存在的浅表层识别标志。地震识别标志主要有似海底反射层(BSR)和振幅空白带2种标志,地形地貌标志包括海底麻坑、海底滑塌、丘状体、泥火山、冷泉系统等,水体标志主要为羽状流。在水深1000 m和2900 m的站位已分别钻获水合物样品。莫克兰增生楔丰富的水合物识别标志可能与低速、低角度的俯冲地质背景有关,使该区水合物存在指示兼具主动大陆边缘和被动大陆边缘的特征。综合研究区的异常标志分布特征,推测增生楔中部和西部的背斜脊及其附近区域是天然气水合物远景区。The Makran accretionary prism located in the northern Arabian Sea is formed by the subduction of the Arabian plate beneath the Eurasian plate in a northerly direction at low speed and low angle,and there are abundant gas hydrate resources in the accretionary prism.Based on the high-resolution multi-channel seismic data,sub-bottom profile and multi-beam echo sounding data acquired by China in 2019,combined with the former investigation results,this paper discusses the shallow and submarine identifications of gas hydrate in the Makran accretionary prism.The seismic identifications mainly include bottom simulating reflector(BSR)and acoustic blank zone.The topographic and geomorphic signs include submarine pockmark,submarine slump,mound,mud volcano and cold seeps system.The water body signs mainly is flare.Gas hydrate samples have been drilled at the stations with water depth of 1000 m and 2900 m respectively.The abundant hydrate identifications of Makran accretionary prism may be related to the low velocity and low angle subduction geological background,which makes the hydrate identifications in this area show the characteristics of active continental and passive continental margins.Based on the distribution characteristics of identifications in the study area,the anticlinal ridges and theiradjacent areas in the central and western parts of accretionary prism are the gas hydrates prospective areas.

关 键 词：莫克兰增生楔 天然气水合物 地震识别标志 地形地貌标志 水体标志 矿产勘查工程 

分 类 号：P618.13[天文地球—矿床学]