松辽盆地晚中生代火山活动与天然气成藏  

Late Mesozoic volcanic activities in Songliao Basin:Implications for gas generation and accumulation

作　　者：孟凡超[1] 刘嘉麒[1] 

机构地区：[1]中国科学院地质与地球物理研究所,北京100029

出　　处：《地质科学》2010年第3期807-821,共15页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家973项目(编号:2009CB219301)资助

摘　　要：松辽盆地晚中生代主要发育了两期大规模的火山活动,形成了火石岭组和营城组火山岩地层。火山活动高峰期分别为150 Ma和110 Ma,其中以营城组火山活动规模较大,持续时间较长,对油气的生成与成藏影响最大。晚中生代火山活动贯穿了火石岭组和沙河子组气源岩的主生烃期,加速了有机质的成熟和演化。火山喷发早于火山岩气藏的主成藏期,为气藏的形成提供了优质的储层和运移通道,有利于气藏的保存。营城组火山岩储层裂缝中充填大量的方解石、石英或岩浆浆屑等后期热液流体,其中粗面岩裂缝中岩浆浆屑的K-Ar全岩年龄为72.98 Ma,该期热液活动对火山岩储层的后期改造、天然气的运移及CO_2气藏的形成等具有重要作用。Late Mesozoic volcanic activities were divided two periods in Songliao Basin, which constitute Huoshiling and Yingcheng Formation,respectively. The ages of volcanic rocks show two peak values that are 150 Ma and 110 Ma. The volcanoes erupted most intensively in Yingcheng Formation,lasting a long time. There were always volcanisms in Late Mesozoic, while the source rocks of Huoshiling and Shahezi Formations were generating hydrocarbons. Volcanism efficiently enhanced the maturity. It is advantaged for gas pools that the volcanoes erupted before hydrocarbon accumulating,because volcanisms can make migration pathway and volcanic rocks are good reservoirs. There are hydrothermal fluids such as calcite, quartz and magma deposits in volcanic fractures. The K-At age of magma deposits in trachyte fractures is 72.98 Ma, which is important for volcanic reservoirs reconstructed, gas migration and CO2 accumulating.

关 键 词：松辽盆地 火山活动 生烃史 成藏史 热液流体 

分 类 号：P618.13[天文地球—矿床学]