松辽盆地白垩系火山岩气藏有效储层特征及成因  

Characteristics and genesis of the effective volcanic gas reservoirs of the Lower Cretaceous,Songliao Basin

作　　者：黄玉龙[1] 刘春生[2] 张晶晶[2] 高有峰[3] 

机构地区：[1]吉林大学地球科学学院,吉林长春130061 [2]大庆油田勘探开发研究院,黑龙江大庆163712 [3]吉林大学古生物学与地层学研究中心,吉林长春130026

出　　处：《天然气地球科学》2017年第3期420-428,共9页Natural Gas Geoscience

基　　金：国家重点基础研究发展计划"973"项目(编号:2012CB822002);国家自然科学基金项目(编号:41472304)联合资助

摘　　要：依据80口钻井1 045m岩心描述,820件薄片鉴定和全直径岩心物性分析,以及220件压汞测试结果,结合试气产能资料,对松辽盆地北部徐家围子断陷白垩系营城组火山岩气藏有效储层特征及成因进行研究。结果表明:有效储层主要分布于流纹质熔结凝灰岩、流纹岩、粗面岩和玄武岩4类优势岩性,残余的原生气孔和粒间孔、石泡孔、溶蚀孔以及冷凝收缩缝5类有效孔隙贡献最大,孔隙结构具有大孔隙—细喉道的构成特点,喉道半径以微米级至纳米级为主。与非有效储层相比,火山岩有效储层发育相对粗大的喉道,具备低排驱压力和高进汞饱和度。基质孔隙和喉道对火山岩有效储层的渗透性能起控制作用,挥发份逸出作用和溶解作用是火山岩有效储层形成的关键因素。通过有效孔隙成因分析认为,流纹岩有效储层为原生孔隙型,玄武岩和粗面岩有效储层为原生孔隙充填残余—次生溶蚀改善型,流纹质熔结凝灰岩有效储层为原生孔隙压实残余—次生溶蚀改善型。In Xujiaweizi Depression of northern Songliao Basin,characteristics and genesis of effective volcanic reservoirs in the Lower Cretaceous Yingcheng Formation were studied on basis of data and information from eighty drilled wells including observation and sampling of 1 045 meters long core intervals,820 sets of thin section analyses and porosity permeability tests with full diameter cores,220 pieces of mercury injection tests,and also with the results of gas productivity capacity tests by each well.It indicates that effective reservoirs are primarily developed in rhyolitic ignimbrite,rhyolite,trachyte and basalt.Effective pore spaces are composed of unfilled vesicles,residual inter-granular and inter-spherulite pores,lithophysal cavities,dissolution pores and contraction fractures.The pore network of volcanic reservoirs is characterized as large pores connected by very narrow pore throats,while the pore throat size ranges from nanometers to micrometers.Compared with non-effective reservoirs,pore throats of effective volcanic reservoirs are relatively wide,which leads to low displacement pressure and high mercury injection saturation.Matrix porosity and pore throats are significant to reservoir permeability,while volatiles degassing and dissolution processes are key factors to the formation of effective volcanic reservoirs.According to the contribution of different effective reservoir porosities,rhyolitic effective reservoirs are characterized to be primary porosity types,basaltic and trachytic effective reservoirs are residual unfilled primary porosity and secondary dissolution porosity types,and the rhyolitic ignimbrite effective reservoirs are residual undercompacted intergranular porosity and secondary dissolution porosity types.

关 键 词：火山岩气藏 有效储层 孔隙结构 白垩系营城组 徐家围子断陷 松辽盆地 

分 类 号：TE122.23[石油与天然气工程—油气勘探]