【作者】 杨家静；

【导师】 陈景山； 沈昭国；

【作者基本信息】 西南石油学院 ， 油气田开发工程， 2002， 博士

【摘要】 在研究乐山～龙女寺古隆起的烃源条件、灯影组储层发育及演化特征、灯影组储层流体地化特征、乐山～龙女寺古隆起构造演化与圈闭的形成和灯影组油气运移聚集分析的基础上，本论文试图通过对高科1井纵向寒武系烃源岩、震旦系储集岩剖面的解剖，结合乐山～龙女寺古隆起上其他地区已有资料，探讨威远震旦系气藏的形成演化规律，并对古隆起震旦系有利区块的勘探前景进行评价。 在烃源条件的研究中，通过对储层沥青与烃源岩有机质中生物标志化合物的对比研究，明确了乐山～龙女寺古隆起震旦系的天然气主要来源于寒武系筇竹寺组的黑色页岩。提出黑色页岩分布广，厚度大，有机质丰度高，类型好，生烃能力强，现今己处于过成熟演化阶段的认识。烃源岩厚度分布、构造沉积埋藏情况和热演化历程因在乐山～龙女寺古隆起上所处的构造部位的不同而既有共性又有差异，表现为自深1井以南的南部凹陷烃源岩厚度大、进入热演化的时期早，而以威117井为代表的上斜坡和以高科1井为代表的古隆起顶部烃源岩厚度渐小、进入热演化的时期晚，呈现烃源岩成烃高峰期参差、供烃时间长的特点。这些表明烃源岩有机质热演化与古隆起的演化密切相连，乐山～龙女寺古隆起构造演化、沉积埋藏、古地温变化对有机质的热演化有明显的控制作用。通过烃源岩有机质热演化研究，提出乐山～龙女寺古隆起烃源岩有机质热演化分为三期，即初始生烃阶段，对应于下寒武统烃源岩的埋藏期；生烃停滞阶段，对应于下寒武统烃源岩的抬升期；二次生烃阶段，对应于下寒武统烃源岩的再埋藏期。志留纪末～早二叠世，凹陷区大量生油；三叠纪末，斜坡带及顶部大量生油。 灯影组固态碳沥青是从烃源层生成的原油运移进入储层后经热演化残留的产物。通过对碳沥青的产状和热演化指标的分析，认为碳沥青是极高古地温条件下在热作用下趋于演化终点的产物。碳沥青广泛充填于溶蚀孔洞缝和早期构造缝中，使储层物性变差并可能形成沥青封堵带，导致后期油气运移或聚集困难，而晚期的构造缝却可以成为油气的运移通道并使油气聚集成藏。首次提出分布在储层溶洞、溶孔和溶蚀缝内的碳沥青，其全岩沥青反射率的不同数值反映了不同演化阶段有机质生成的沥青的充填或者前期进入储层沉淀的沥青在后期埋藏过程中继续演化的结果。从天然气的碳同位素组成分析，不同圈闭捕获了不同热演化阶段的油裂解气和干酪根裂解气，即资阳古圈闭捕获的主要是油裂解气，而威远气田和高石梯－安平店构造带捕获的既有油裂解气也可能有干酪根裂解气。 通过对古隆起的构造演化的研究，认为加里东期、印支期－燕山期和喜山期是圈闭形成的主要时期。乐山－龙女寺古隆起寒武系－震旦系含油气系统的油气生成和运移聚集的关键时刻为志留纪末、晚三叠世末和白圣纪末，其中加里东期古圈闭如遂宁古圈闭和川西高点、印支期形成的资阳古圈闭和燕山末－喜山期崛起的威远背斜以及由遂宁古圈闭演化形成的高石梯－安平店－磨溪－龙女寺构造带、资阳古圈闭演化形成的资阳古背斜群圈闭和1！洒高点演化形成的大兴场－汉王场构造带对油气的捕获并聚集成藏较为有利。 通过对威远、资阳震旦系气藏形成演化的分析，在前人工作的基础上讨论了资阳、威远地区油气藏形成演化模式，并对威远油气藏成藏的后生变化进行了初步讨论。 首次指出威远构造及乐山－龙女寺古隆起边缘油气初次成藏后遭受过水洗作用的改造。水洗作用发生的时间可能在威远构造初次聚油以后，联系到威远古构造是印支晚幕－燕山期由单斜崛起成为古背斜并逐渐扩大并聚集油气，推测水洗作用发生的时间可能为株罗纪末的燕山晚幕；威远构造具有两次成藏或者说有两次油气注入，资阳古圈闭在燕山早期继续存在而于晚期逐渐消失，并于喜山期消失在威远古背斜的西北翼，随着埋深加大，在构造反转的过程中，不排除资阳古圈闭、高石梯－安平店－龙女寺构造带处于湿气－凝析油阶段的油裂解气以及后期烃源岩于酪根裂解气运移进入威远古背斜。 从目前的勘探现状看，勘探重点应坚持选择在威远以东、华銮山以西地区。该区保存条件好、古今构造变动相对较小、拥有于二叠纪前形成的大型遂宁古背斜圈闭演化而来的高石梯－安平店－磨溪－龙女寺潜伏构造带和资阳古圈闭演化形成的资阳古背斜群，且油气生成与圈闭形成在时间和空间上匹配，具有良好的含气有利条件。更多还原

【Abstract】 The laws of formation and evolution of Sinian gas pools in Weiyuan and Ziyang areas are clarified and the Sinian plays in Leshan-Longnusi Paleo-uplift are evaluated through the geochemical dissection of Cambrian source rock and Sinian reservoir rock of Gaoke 1 well, and on the basis of following researches: hydrocarbon source conditions, formation and evolution of Dengying reservoir, geochemical characters of reservoir fluids, structural evolution and trap formation in Leshan-Longnusi Paleo-uplift, and migration and accumulation of oil and gas in Dengying reservoirs.It is clearly pointed out that Sinian natural gas of Leshan-Longnusi Paleo-uplift originated from Qiongzhusi black shales, Lower Cambrian, through the biomarker correlation study in reservoir soluble bitumen and extracts of source rocks. Distribution of black shale is wide and thickness of black shale is big, abundance of organic matter is high and the type of organic matter is good, and the ability of hydrocarbon generation is strong. At present organic matter of source rock has already been in over-mature thermal evolution stage. The distribution of source bed thickness, sedimentary burial history, and the thermal evolution course of Cambrian source rock are common and different, because of being the different structure positions in Leshan -Longnusi Paleo-uplift. Source rocks are thick in South Depression which is southern from Zishen 1 well and the time of entering Oil window of organic matter is earlier. Source rocks are gradually thinner from Upper Slope (Wei 117 well) to Top of Paleo-uplift (Gaoke 1 well) and the time of entering Oil window of organic matter is later. The hydrocarbon creating peak period is different in various areas. The period of hydrocarbon supply is long. All of those show that the thermal evolution of source rock organic matter are closely associated with the evolution of paleo-uplift, the thermal evolution of source rock organic mattermhave been obviously controlled by structural evolution, sedimentary bural history and paleotemperature in Leshan -Longnusi Paleo-uplift. The thermal evolution courses of organic matter in Leshan-Longnusi Paleo-uplift are divided into three periods. The early hydrocarbon generation stage accompanies with the first burial period of Lower Cambrian source rock, the hydrocarbon generation stagnation stage accompanies with the rise period of structure, and the second hydrocarbon generation stage accompanies with the second burial period of Lower Cambrian source rock. In South Depression oil large generation took place in terminal of Silurian-Early Permian and in Upper Slope it took place in terminal of Triassic.The solid anthraxolites in Dengying carbonate reservoirs are residual matter of oil which had been originated from Qiongzhusi black shales and had been migrated into Dengying reservoir and had been later undergone thermal evolution in Dengying reservoirs. Through the analysis of their occurrence and evolution parameters, the solid anthraxolites are thought to be the results of thermal evolution under high paleotemperature. The physical property of Dengying reservoirs becomes bad because of solid anthraxolites extensively been filled into the early structure fissures and tar mat probably been formed, so that the migration and accumulation of oil and gas are later much difficult in Dengying reservoirs. On the other hand, the later structure fissures are likely the migration channels that lead oil and gas accumulation in Dengying reservoirs. It is the first time to point out that the different reflectance ratios of whole rock bitumen are the results of the different thermal evolution stages. Bitumen were filled into Dengying reservoir accompanying with oils having been migrated from source bed into reservoir bed, and continuously evolved in reservoir-inside and finally formed solid anthraxolites, as the residue of oil thermal evolution existing in leach holes, corroded hollows and corroded fissures of reservoir rock in the course of succeeding bury. Based on the analysis of natura更多还原