海洋天然气水合物勘查和识别新技术:地质微生物技术  

Geomicrobiology as a New Tool for Exploration of Marine Gas Hydrates

作　　者：苏新[1] 陈芳[2] 张勇[1] 王媛媛[1] 焦露[1] 蒋宏忱[1] 董海良[1,3] 

机构地区：[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 [3]迈阿密大学地质系,俄亥俄州牛津45056

出　　处：《现代地质》2010年第3期409-423,共15页Geoscience

基　　金：国家重点基础研究发展计划项目(2009CB219502);国土资源部公益性行业科研专项(200811014-02);中国地质调查局基础调查项目(GZH200200203-02-01)

摘　　要：当前国内外海洋天然气水合物勘查和评价发展趋势要求有更多具有精细探测和评价功能的技术,这给地质微生物水合物探测技术的研发和应用提出了需求和挑战。简要介绍了当前水合物成藏或沉积环境研究中所涉及的主要微生物类别及其主要关系,它们绝大多数是适应海底深部低温高压环境的厌氧极端生物。其中重要类群是为天然气提供气源的产甲烷古生菌、参与甲烷厌氧氧化过程的甲烷氧化古生菌和硫酸盐还原细菌。介绍了国内外几个地质微生物探测技术的实例,包括历史悠久的"微生物油气勘探"技术、近十年来发展起来的微生物计数法、群落结构和标志类别法;另外,对新露头角的微生物生物标志物法等其他方法也给予简要介绍。For exploration of marine gas hydrates,three major techniques were commonly used for marine geological survey and for indication of existence of gas hydrates： geophysical techniques,geochemical techniques,and geological techniques.It is the trend to employ advanced and multi-proxy or techniques to determine and identify the existence and distribution of marine gas hydrates.This trend provides both of chance and challenge for using geomicrobiological techniques in this field.Marine gas hydrates were formed in deep sea sediments under high pressure and low temperatures.Abundant and a variety of microbes are living in the gas-hydrate-bearing sediments and several groups of microbes play significant roles in formation and decomposition of gas hydrates.For example,methanogens produce methane as a metabolic byproduct under anoxic conditions in deep sediments,providing biogenic methane sources for formation of gas hydrate;on the other hand,methanotrophic microbes rely on methane as their sole carbon and energy sources,consuming methane released from gas hydrates through complex processes of anaerobic methane oxidation,thus showing very sensitive response to variation of methane flux in sediments.This paper introduced several cases for geomicrobiological techniques used in exploration of gas and gas hydrates：（1）microbial oil survey technique（MOST）;（1） Analysis of abundance of microbial cells（microbial counts）in correlation to concentration of methane in gas-hydrate-bearing sediments;（3）studies on microbial communities（microbial community analysis） in correlation to distribution of gas hydrates in sediments.It is seen that MOST and Microbial counts can be used as prospecting techniques during marine geological survey for gas hydrates,while techniques of microbial community analysis and biogeochemical analysis are of importance for identification of existence of gas hydrates in sediments and the sources of methane in gas hydrates.

关 键 词：地质微生物 微生物丰度 群落结构 甲烷 水合物识别技术 

分 类 号：P736.2[天文地球—海洋地质]