青海南部乌丽—开心岭冻土区天然气水合物气源条件研究

Gas hydrate sources in Wuli-Kaixinling permafrost, southern Qinghai province

唐世琪 卢振权 罗晓玲 王婷 谭盼盼

Tang Shiqi Lu Zhenquan Luo Xiaoling Wang Ting Tan Panpan

中国地质大学(北京) 地球科学与资源学院, 北京 100083 2. 中国地质调查局 油气资源调查中心, 北京 100029 3. 中国地质调查局 发展研究中心, 北京 100037

School of Earth Sciences and Resources, China University of Geosciences (Beijing), Beijing 100083, China 2. Oil and Gas Survey, China Geological Survey, Beijing 100029, China 3. Development and Study Center, China Geological Survey, Beijing 100037, China

以近两年天然气水合物资源勘查与试采工程国家专项在青海南部乌丽—开心岭冻土区开展的气源岩调查资料为基础,重点对上二叠统乌丽群那益雄组和上三叠统结扎群巴贡组烃源岩的有机地球化学指标进行分析.结果显示研究区上二叠统乌丽群那益雄组和上三叠统结扎群巴贡组烃源岩有机质含量中等,有机质类型主要为III型,且成熟度较高,大多数样品有机质达到高成熟或过成熟,处于生湿气和干气阶段,能够产生大量烃类气体来满足该区天然气水合物形成时所需的气源条件;上二叠统那益雄组泥岩和上三叠统巴贡组灰岩可成为该区天然气水合物的主要气源岩.

Based on the past two years' data on gas source survey in compliance with the National Thematic Project of Gas Hydrate Resources' Exploration and Test-Production Engineering in the Wuli-Kaixinling permafrost of the southern Qinghai province, organic geochemical indicators were analyzed on the hydrocarbon (gas) source rocks of the Nayixiong Formation in the Upper Permian Wuli Group and the Bagong Formation in the Upper Triassic Jiezha Group. Results showed that organic matter contents were at moderate levels in the hydrocarbon (gas) source rocks of the two formations. The main organic matter was type III with high maturity. For most samples, organic matter was mature or over-mature, at the wet to dry gas phase. The source rocks produced a large amount of hydrocarbon gases to meet the needs of gas hydrate formation. Mudstones in the Nayixiong Formation in the Upper Permian Wuli Group and limestones in the Bagong Formation in the Upper Triassic Jiezha Group worked as major gas source rocks for gas hydrate formation.

国家自然科学基金项目(41073040)和天然气水合物勘查与试采专项项目(GZHL20110310,GZHL20110311,GZHL20110314)资助.

https://doi.org/10.11781/sysydz201501040