音频大地电磁测深在祁连山哈拉湖坳陷天然气水合物调查中的应用  

The application of audio frequency magnetotelluric sounding to the investigation of gas hydrate in the Hala Lake depression of the Qilian Mountain

作　　者：何梅兴[1,2,3] 裴发根 方慧[1,2,3] 张鹏辉 刘畅往[1,2,3] 杜炳锐 吕琴音[1,2,3] 仇根根 

机构地区：[1]国土资源部地球物理电磁法探测技术重点实验室,河北廊坊065000 [2]国家现代地质勘查工程技术研究中心,河北廊坊065000 [3]中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000

出　　处：《物探与化探》2017年第6期1167-1174,共8页Geophysical and Geochemical Exploration

基　　金：国家127专项项目(GZH201400302);中国地质调查局地质调查项目(DD20160224;DD20179352);国家高技术研究发展计划("863计划")课题(2012AA061403)

摘　　要：祁连山哈拉湖坳陷与已发现天然气水合物的祁连山木里地区有相似的成藏条件,是高原冻土区水合物勘查的重点区域。为了调查祁连山哈拉湖坳陷的天然气水合物资源前景,查明冻土层厚度及断裂分布特征,利用音频大地电磁测深在哈拉湖地区进行了测量,从电性结构特征测区内划分了3个凹陷区、2个凸起区和26条断裂,分析了哈拉湖地区冻土层发育特征。结合测区内构造条件、冻土条件及顶空气甲烷异常区,指出哈拉湖南部和北部靠近断裂附近对天然气水合物成藏较有利。The Hala Lake depression in Qilian Mountain has similar conditions for the discovery of the gas hydrate in the Qilian area, which is the key area of the hydrate exploration in the permafrost region of the Tibetan Plateau. By analyzing 45 sections in Hala Lake and conducting audio frequency magnetotelluric survey with total length of 606.4 km, the depression structure and distribution of frozen soil were studied for their electrical characteristics. According to the east and west distribution electrical characteristics of Hala Lake ar- ea, the authors mainly analyzed structural features of the east part and the west part of Hala Lake. It is shown that the inner depression testing area of Hala Lake can be divided into 3 depression areas and 2 upwefling areas. The authors also analyzed the distribution and scales of depression areas and 2 upwefling areas. 26 fractures were recognized within the depression testing zone of Hala Lake. These fractures mainly strike in NW--SE direction. The main controlling fractures in the testing area were also discussed. The authors summa- rized the development characteristics of frozen soil in Hala Lake area and analyzed the main factors influencing the development of the frozen soil. According to the abnormal structure, frozen soil and geochemistry of hydrocarbons, the authors indicate the favorable areas for natural gas hydrate exploration.

关 键 词：天然气水合物 冻土 电磁法 哈拉湖坳陷 

分 类 号：P631[天文地球—地质矿产勘探]