徐家围子断陷安达凹陷火石岭组天然气成藏条件分析  

Analysis of gas accumulation conditions of Huoshiling Formation in Anda sag of Xujiaweizi fault depression

作　　者：刘红艳[1] LIU Hongyan(Exploration and Development Research Institute of Daqing Oilfield Company Ltd.,Daqing 163712,Heilongjiang,China)

机构地区：[1]大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712

出　　处：《世界地质》2022年第1期153-161,共9页World Geology

基　　金：中国石油天然气股份公司重大科技专项(2016E-0203)。

摘　　要：DS28井的勘探研究表明徐家围子断陷火石岭组具有良好的勘探前景。笔者通过对岩芯地化测试、铸体薄片、孔隙度测试等资料的分析,探究安达凹陷火石岭组天然气的气源条件、储层特征、盖层条件和成藏模式,以期深入认识松辽盆地北部火石岭组天然气富集规律,指出有利勘探区带和勘探方向。研究表明,安达凹陷火石岭组具备天然气藏形成的基本地质条件。火石岭组、沙河子组烃源岩为天然气成藏提供了充足的气源,其中沙河子组作为主力烃源岩,有机质丰度高,与火石岭组侧向对接,供烃条件有利;凹陷东西两侧SN向展布的火山岩体为气藏形成提供了储层条件;区域分布的登娄库组泥岩盖层提供了有效的封盖条件;早期拉张、后期反转定型于登娄库组沉积时期的古构造早于烃源岩生排烃时间,成藏匹配好。源岩-岩相控制气藏分布,爆发相储层物性相对较好,是有利岩相类型,优质烃源岩控制气藏分布,结合气藏模拟,认为东部鼻状构造带上的大型火山机构是天然气勘探的有利方向。The exploration discovery of Well DS28 shows that the Huoshiling Formation in the Xujiaweizi fault depression has good exploration prospect.Through the analysis of core geochemical test,cast thin section,porosity test and other data,the authors explore the gas source conditions,reservoir characteristics,caprock conditions and reservoir forming mode of the Huoshiling Formation in the Anda sag.The purpose is to deeply understand the natural gas enrichment law of the Huoshiling Formation in the northern Songliao Basin and point out the favorable exploration area and direction.The study shows that the Huoshiling Formation in the Anda sag has the basic geological conditions for the formation of natural gas reservoirs.The source rocks of the Huoshiling and Shahezi formations provide sufficient gas source for natural gas accumulation.As the main source rock,the Shahezi Formation have high organic matter abundances and it was lateral docking with the Huoshiling Formation,with favorable hydrocarbon supply conditions.Volcanic rocks distributed in the SN direction on the east and west sides of the sag provide reservoir conditions for the formation of gas reservoirs.The regional distribution of the mudstone caprock of the Denglouku Formation provides effective capping conditions.The paleostructure formed during the Denglouku period in the early extension and later inversion is earlier than the hydrocarbon generation and expulsion time of source rocks,and the matching of gas trapping and gas supply is good.Source rocks and lithofacies control the distribution of gas reservoirs.The reservoir with erupting facies has relatively good physical properties and is a favorable lithofacies type.High quality source rocks control the distribution of gas reservoirs.Combined with gas reservoir simulation,it is considered that the large volcanic apparatus on the eastern nose structure belt are favorable directions for natural gas exploration.

关 键 词：安达凹陷 火石岭组 天然气成藏条件 火山岩 成藏匹配 

分 类 号：P618.13[天文地球—矿床学]