【作者】 张闻林；

【导师】 张哨楠；

【作者基本信息】 成都理工大学 ， 矿产普查与勘探， 2007， 博士

【摘要】 论文针对川西地区侏罗系隐蔽气藏的地质特点，应用油气有机地球化学、油气成藏动力学、地震地层学、层序地层学理论，对烃源岩的生烃能力、油气二次运移的动力、疏导条件和油气聚集成藏机理进行了系统研究，总结了气藏形成的主要控制因素和气藏分布的基本规律。并结合大兴西地区进行了勘探目标研究。论文研究突出了多学科、多领域、多层次相互交叉融合的特色，主要在以下几方面取得了主要成果和认识：1．通过气源对比研究表明，侏罗系气藏的天然气主要来自须家河组须五段～须二段，并计算出白马庙构造天然气混合比例。2．在成藏条件研究的基础上，总结出川西地区侏罗系气藏各种类型的成藏模式。首次提出川西地区北部侏罗系存在异常高压封存箱成藏模式，并建立了北部地区侏罗系气藏异常高压封存箱成藏模式。3．通过流体势、压力、生烃强度与疏导条件等系统研究，指出川西南部地区上三叠统油气经过砂岩层和裂缝系统等疏导体系进行垂向和侧向运移。首次提出在侏罗系气藏成藏过程中，地层抬升卸压造成的吸附气膨胀，是各种成藏机制中晚期形成气藏的重要的补充气源。水溶脱气在喜山期侏罗系最后成藏时期也提供了一定量的气源。在成藏机理的综合分析基础上，建立了川西地区侏罗系隐蔽气藏的抬升卸压、水溶脱气成藏的形成模式。4．根据野外露头、岩心观察和测井资料，首次在有利目标地区的大兴西～名山地区对侏罗系沙溪庙组进行高分辨层序地层学研究，经过地震地层学研究划分出地震相，进而转换为沉积微相。总结出储层在纵、横向的分布规律，并且初步预测了储层分布的有利区。5．．综合自然伽玛反演、速度反演、孔隙度反演的“三步法”对大兴西～名山重点地区38条测线共计805.16km进行地震特殊处理，对储层分布进行了综合预测研究，明确了沙溪庙组储层在平面和剖面上的分布特征。在此基础上，应用国际先进的Fraca裂缝预测软件对裂缝发育区进行预测分析，指出近期勘探的有利目标。更多还原

【Abstract】 Subtle oil and gas reservoir exploration is a problem at present. In view of thegeological feature of the Jurassic subtle gas reservoir in western Sichuan province, this papersystematically studied the hydrocarbon generative capacity of source rock, the dynamics andconducting conditions of secondary hydrocarbon migration, and hydrocarbon accumulation andformation mechanism based on hydrocarbon organic geochemistry, reservoir formation dynamics,seismic stratigraphy, sequence stratigraphy and subtle oil and gas reservoir exploration theory. Italso summarized the main control factors for the formation of gas reservoir and its basicdistribution laws. The prominent characteristic of this study was the cross and mixing ofmultidisciplinary, multi-fields and multi-levels. New results and understandings were achieved asthe following:Based on source rock organic geochemistry feature analysis and the hydrocarbongenerative capacity simulation, it was pointed out that in western Sichuan provincemost Jurassic stratigraphy can not generate hydrocarbon except the low hydrocarbongenerative capacity of Ziliujing Member in local area. The gas source was mainlyfrom the underlying coal system layer of upper Triassic. Gas source correlationresearch showed that natural gas in Jurassic reservoir was mainly generated from No.in Xujiahe Member.Through typical gas reservoir analysis, it was summarized that in the southernarea of western Sichuan province the sedimentation and diageneses were the maincontrol factors for Jurassic subtle gas reservoir with lithologic traps andlithologic～structural combination traps. The sedimentation controlled the spatialdistribution and the thickness of sand body, sand granularity and feldspar content, etc.,while corrosion and fracture decided the developing degree of porosity andpermeability of effective reservoirs.Based on the systematic study on fluid potential, fluid pressure, hydrocarbon generation and conducting conditions, it was pointed out that the upper Triassic hydrocarbon in the southern area of western Sichuan province migrated v ertically and laterally through conducting systems as sand layer and fractures.Natural gas in the upper Triassic erupted vertically into the Jurassic reserves along the fracture system, while on the lateral the region was controlled by fluid potential so gas migrated and accumulated southeastward to the high partswith low potential. Subtle gas reservoir formation pattern was set up on the basis of comprehensive analysis on reservoir formation mechanism.Based on the field outcrops, coring observation and well logging data, andsequence stratigraphy principle, this paper systematically studied the sequenceframework of Jurassic in this area. On this basis high resolution sequence stratigraphyresearch was carried out for the first time on Jurassic Shaximiao Member inDaxingxi～Mingshan region in the favorable target zone, and summarized the verticaland horizontal distribution laws of the reserves. It also predicted the favorable zonefor reservoir distribution.Combined the methods of natural gammar inversion, velocity inversion withporosity reversion, 38 seismic lines, totally 805.16km, was specially processed, andcomprehensive prediction on reservoir distribution was carried out. Also the planeand section distribution feature of Shaximiao Member reservoir was made clear. Onthis basis the advanced Freca fracture prediction software was used for prediction andanalysis on fracture developing region to decide the recent favorable explorationtarget.更多还原