川东地区页岩岩相及其控气性特征研究

发布时间：2018-04-25 02:31

本文选题：页岩 + 五峰组-龙马溪组　；参考：《西南石油大学》2015年硕士论文

【摘要】：本文依托于国家973计划“优质页岩气储层预测及精细表征”课题,以川东及周缘地区的五峰组-龙马溪组海相页岩作为本次研究的主要工作对象。过去人们普遍认为特定层序下的泥页岩变化程度较小,因而对泥页岩的岩相研究相对较少,近几年来,随着人们对页岩气的勘探开发越来越重视,寻找良好的可压性页岩气富集带成为了泥页岩勘探的目标,而这两个因素都与岩相直接相关,因此,本文在对川东及周缘地区五峰组-龙马溪组页岩储层沉积特征进行研究的基础上,对川东X地区的页岩岩相进行了分类,且分析了页岩岩相及其控气性的特征,并对有利生产的页岩岩相进行了预测。取得的成果和认识如下： (1)对长宁双河、习水骑龙村、綦江观音桥三个野外露头剖面进行了实地勘测,这三个野外剖面的五峰组-龙马溪组地层都沉积了一套富有机质暗色页岩,沉积相上可划分为深水陆棚亚相与浅水陆棚亚相两类。在此基础上,选取川东X地区的6口直井作为沉积序列分析的标准井,运用相标志模式对比法,对6口直井进行了单井沉积微相划分,弄清了X地区五峰组-龙马溪组沉积微相在垂向和平面上的分布特征。 (2)建立了川东五峰组-龙马溪组页岩的沉积模式,认为川东五峰组-龙马溪组页岩主要受到了构造和海平面升降的影响,整个川东地区在晚奥陶世到早志留世处在一个被各隆起所围限的半滞留隆后深水盆地之中,从而沉积了一套暗色富有机质页岩。 (3)在考虑页岩的储气性与可采性的基础上,通过野外露头、岩心观察及显微镜下分析,根据泥页岩岩性组合和页岩有机质与硅质的含量,对川东X地区五峰组-龙马溪组海相页岩进行了岩相的划分。将X地区五峰组-龙马溪组下段页岩分为富碳高硅页岩相、高碳高硅页岩相等19种页岩岩相。 (4)在对页岩气赋存机理及页岩含气量影响因素进行分析研究的基础上,通过对各种岩相页岩与其储层物性、页岩含气量和生产井无阻流量的对比统计,可知富碳高硅页岩相、高碳高硅页岩相为含气量和产气量最高的岩相类型,而高碳中硅页岩相、高碳中硅含粉砂页岩相、高碳中硅粉砂质页岩相也具有较高的含气量。
[Abstract]:Based on the national 973 project "Prediction and fine characterization of high-quality shale gas reservoir", the marine shale of Wufeng formation-Longmaxi formation in eastern Sichuan and its surrounding area is taken as the main object of this study. In the past, it was generally believed that the shale under the specific sequence had little change, so the lithofacies of shale was relatively little. In recent years, with the development of shale gas, more and more attention has been paid to the exploration and development of shale gas. Finding a good compressible shale gas enrichment zone has become the target of shale exploration, and both factors are directly related to lithofacies. On the basis of studying the sedimentary characteristics of shale reservoir of Wufeng formation and Longmaxi formation in eastern Sichuan and its surrounding area, this paper classifies the shale lithofacies in X area of eastern Sichuan, and analyses the characteristics of shale lithofacies and its gas-controlling property. The shale facies favorable for production are predicted. The results and perceptions are as follows: 1) three field outcrop sections of Shuanghe River in Changning, Jilongcun in Xishui and Guanyin Bridge in Qijiang have been investigated in the field. The strata of the Wufeng formation and Longmaxi formation in these three field sections have all deposited a set of dark shale rich in organic matter. The sedimentary facies can be divided into deep water shelf subfacies and shallow water shelf subfacies. On this basis, six vertical wells in X area of East Sichuan are selected as standard wells for sedimentary sequence analysis, and six vertical wells are divided into single well sedimentary microfacies by using phase marker pattern correlation method. The distribution characteristics of sedimentary microfacies in vertical and plane of Wufeng formation and Longmaxi formation in X area are clarified. (2) the sedimentary model of the shale of Wufeng formation and Longmaxi formation in eastern Sichuan is established. It is considered that the shale of Wufeng formation and Longmaxi formation in eastern Sichuan is mainly affected by structure and sea level rise and fall. From late Ordovician to early Silurian, the whole area of East Sichuan is in a deep water basin, which is limited by each uplift, and a set of dark organic matter rich shale has been deposited. (3) on the basis of considering the gas storage and recoverability of shale, through field outcrop, core observation and microscope analysis, according to shale lithologic assemblage and shale organic matter and siliceous content, The lithofacies of marine shale of Wufeng formation-Longmaxi formation in X area of East Sichuan are divided. The lower member shale of Wufeng formation and Longmaxi formation in X area is divided into rich carbon and high silicon shale facies, and high carbon high silicon shale is equal to 19 kinds of shale lithofacies. (4) based on the analysis of the mechanism of shale gas occurrence and the influence factors of shale gas content, through the comparative statistics of physical properties of various lithofacies shale and its reservoir, shale gas content and unobstructed flow rate of production wells, it can be seen that the rich carbon and high silicon shale are rich in carbon and high in silicon. The high carbon and high silicon shale facies are the lithofacies with the highest gas content and gas production, while the high carbon medium silicon shale facies, the high carbon medium silicon silty shale facies and the high carbon silty silty shale facies also have higher gas content.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13

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