祁连山冻土区天然气水合物中轻烃分析方法及应用

Analysis method and geological significance of C-C light hydrocarbons in natural gas hydrate in permafrost, Qilian Mountain

张敏 何瑜 陈祖林 龚建明

ZHANG Min HE Yu CHEN Zulin GONG Jianming

长江大学 资源与环境学院, 武汉 430100 2. 长江大学 油气资源与勘查技术教育部重点实验室, 武汉 430100 3. 青岛海洋地质研究所, 山东 青岛 266071

School of Earth Environment and Water Resources, Yangtze University, Wuhan, Hubei 430100, China 2. Key Laboratory of Exploration Technology for Oil and Gas Research of Ministry of Education, Yangtze University, Wuhan, Hubei 430100, China 3. Qingdao Institute of Marine Geology, Qingdao, Shandong 266071 China

通过自行研发的一套真空密闭加热脱附以及冷柱头零压力进样装置，对采集到的顶空气样进行轻烃在线分析，实现了天然气水合物轻烃C5-C7化合物的有效检测。根据Kováts保留指数等前人研究成果，对祁连山木里煤田聚乎更矿区天然气水合物轻烃中C5-C7共27个单体化合物进行了定性分析，对该区天然气水合物的轻烃地球化学进行研究。利用甲基环己烷指数对该区天然气水合物成因类型进行划分，揭示木里冻土区天然气水合物气体有2种成因3种类型，其中以混合型为主，并伴有少部分的油型气和煤型气。

A sample introduction device of vacuum thermal desorption, cold on-column and zero-pressure was built for the identification of C5-C7 light hydrocarbons in gas hydrate. On the basis of previous Kováts index research, 27 compounds of C5-C7 light hydrocarbons were identified, which provided a foundation for the geochemical study on light hydrocarbons in gas hydrate in the Juhugeng mining area, Muli coal field, Qilian Mountain. Two genetic types of gas hydrate in the Muli permafrost were divided into three types, including oil-type, coal-type and mixed-type gas based on the methylcyclohexane index. The mixed-type gas predominates in the Muli permafrost, while the other two types are in the minority.

国家自然科学基金项目（41273066）资助。

https://doi.org/10.11781/sysydz201803418