【作者】 高慧；

【导师】 方念乔； 姜正龙；

【作者基本信息】 中国地质大学（北京） ， 海洋地质， 2007， 硕士

【摘要】 珠江口盆地是在中国南海北部最大的中新生代沉积盆地,是我国海上重要油气资源基地之一。惠州凹陷位于珠江口盆地东部的珠一坳陷,已发现多个良好油气藏,是盆地油气藏分布的主要凹陷之一。随着新近系勘探程度的加深,对古近系的研究也成了当前油气勘探研究的主要任务。本论文研究了惠州凹陷新生界主要是古近系的油气成藏条件和规律。论文主要从油气成藏条件评价、典型油气藏成藏特征和成藏模式、生烃特征和生烃高峰、油气运聚特征等四方面对惠州凹陷的成藏规律进行研究,并进行了初步的有利构造带优选。惠州凹陷有生、储、盖和圈闭保存等良好的油气成藏条件:古近系有文昌组和恩平组两套烃源岩,主要为中深湖相和河流沼泽相泥岩,有机质较高,为油气的形成奠定了物质基础;有良好的储层和盖层分布,储层以砂岩为主,盖层主要为泥岩盖层,分布有大范围的区域盖层;有良好的储盖组合,存在三套含油组合;具有众多良好的构造圈闭,构造类型以披覆背斜、逆牵引构造为主。盆地模拟计算是研究油气的生烃和运聚特征、油气藏埋藏史的重要方法。盆地模拟计算结果显示:生烃洼陷控制了油气藏的分布,油气藏主要分布在生烃洼陷附近的有效圈闭带,大的生烃中心主要分布在惠西地区;凹陷的主要生烃时期在0-18Ma,即早中新世珠江组沉积中期直到现今,而生烃高峰在0-10Ma,即粤海组开始沉积至现今;地层的流体势以汇聚流为主,多个高势区和低势区使油气向多个不同方向运移,形成了多个油气运聚单元。惠州凹陷的油气藏成藏模式,从成藏期次上分多为两期成藏,从油源上分有单油源和双油源两种成藏模式,构造形式上有陡坡型、隆起型和缓坡型成藏模式。结合二级构造带和烃源岩的生烃特征、地层流体势特征的关系,分析得出XJ24潜山断裂带、HZ21潜山断裂带和HZ13S翘倾构造带为惠州凹陷的最有利的含油构造带。更多还原

【Abstract】 The Pear River Mouth Basin is the maximal Meso-Cenozoic depositional basin in the north of South China Sea and an important base of marine hydrocarbon resources. The Huizhou Sag lies in Zhu I depression, which is in the east of the Pear River Mouth Basin and in Huizhou Sag some good Reservoir has been discovered. With additional exploration of Neocene, the research on Early Teriary is the primary task of current exploration. The dissertation is the research on hydrocarbon-bearing condition and law in Cenozoic of Huizhou sag. The dissertation includes the evaluatation of hydrocarbon-bearing condition, the reservoir-formation characteristic and model of typical reservoir, the characteristic and fastigium of hydrocarbon-generating, the characteristic of hydrocarbon migration and accumulation. Finally, several favorable structures is optimized.There are good hydrocarbon-generating condition, reservoir condition, cap condition and trap condition etc in Huizhou Sag: there are Wenchang and Enping Formations source rocks, which is mainly mudstone of middle-deep lack facies and river-paludal facies. The source rocks have high organic content, and were the material base for hydrocarbon generation; there are good reservoir bed and cap rock, and reservoir bed is mainly sandstone. The cap rock is mainly mudstone and there is extensive regional cap; there are some good reservoir and seal assemblages; there are many structural traps, the type of which are mainly drape and reverse drag anticline.Basin modeling is an important method of studying the characteristic hydrocarbon-generating and hydrocarbon migration. The results of basin modeling show that: the distribution of reservoir is controlled by hydrocarbon-generating low-lying, and the reservoirs mostly lie in effective trap around the hydrocarbon-generating low-lying. The main hydrocarbon-generating centers lie in the western Huizhou Sag; the main hydrocarbon-generating period is 0-18Ma(from the middle deposition period of Zhujiang Formation in Early Miocene to now),and fastigium of hydrocarbon-generating is 0-10Ma(form the beginning deposition of Yuehai Formation to now); the fluid potential of layer is mainly convergent-type, and there are many high fluid potential belts and low fluid potential belts, which make hydrocarbon migrate to some different directions and form some cells of hydrocarbon migration and accumulation.The reservoir-forming model of Huizhou Sag is almost two-step according to reservoir-forming stage, and there are single-source and two-source reservoir according to oil sources. There are three reservoir-forming models of abrupt slope type, apophysis type and gentle slope type according to structural form. Based on the relation of second order structure zone and the characteristic hydrocarbon-generating, the characteristic of the fluid potential, it is analyzed that XJ24 fault zone, HZ21 fault zone and HZ13S structure zone are the most favorable oil-bearing structure zones in Huizhou Sag.更多还原