摘要
东濮凹陷在下古生界奥陶系风化壳与下古近系Es31地层发现了高含CO2气层,通过气源对比分析,古近系Es31的有机气体来源下第三系碎屑岩地层生成的油型气,CO2则来源于石炭—二叠系的煤在二次生烃中伴生CO2气与海相碳酸盐岩高温分解的无机CO2混合形成的;对东濮凹陷两类CO2气源岩高温模拟实验可知,石炭—二叠系煤生气能力是奥陶系灰岩的9倍,煤生成的气体70%~80%为甲烷,含少量的CO2,而灰岩90%以上为CO2气,煤是东濮凹陷最重要的气源岩;通过计算认为:东濮凹陷CO2气的资源量为980×108m3,相当于常规天然气资源量的1/4,具有较大的资源潜力。
Gas layers with high CO_2 content have been recognized in the Lower Paleozoic Ordovician weathering crust and in the Paleogene Es_3~1 in Dongpu sag. Gas-source correlation shows that the organic gas in the Paleogene Es_3~1 is petroliferous gas generated by the Paleogene clastic rocks, while the CO_2 is a mixture of the associated CO_2 generated during secondary hydrocarbon generation of Permo-Carboniferous coal, and the inorganic CO_2 sourced from high temperature decomposition of marine carbonates. High temperature simulation of the two types of CO_2 gas source rocks in Dongpu sag shows that the gas generating capacity of the Permo-Carboniferous coal is 9 times larger than that of the Ordovician limestone. The gas generated by coal contains 70-80% methane but small amount of CO_2; while the gas generated by the Ordovician limestone contains over 90% CO_2. Thus coal is the most important gas source rocks in Dongpu sag. The CO_2 resources in Dongpu sag is estimated to be at 980×10~8m^3, which accounts for one-fourth of the conventional natural gas resources, thus the resource potential of CO_2 is relatively large in the study area.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2006年第11期35-37,共3页
Natural Gas Industry
基金
成都理工大学"油气藏地质及开发工程"国家重点实验室资助项目(PLC200504)部分研究成果.
关键词
二氧化碳
气藏
资源潜力
气源岩
实验室模拟
东濮凹陷
CO_2 gas reservoir, resource potential, gas source rock, laboratory modelling, Dongpu sag