自贡地区嘉陵江组台内滩储层特征与主控因素

Characteristics and Main Controlling Factor of Shoal Reservoir Developed in Jialingjiang Formation of Zigong Area, Southwestern Sichuan

刘宏 王高峰 刘南 乔琳 崔健

LIUHong WANGGaofeng LIUNan QIAOLin CUIJian

西南石油大学地球科学与技术学院, 四川 成都 610500 天然气地质四川省重点实验室, 四川 成都 610500 中海石油(中国)有限公司深圳分公司, 广东 广州 510240 中国石油西南油气田分公司勘探事业部, 四川 成都 610041 中国石油川庆钻探工程有限公司地质勘探开发研究院, 四川 成都 610051

School of Geosciences and Technology, Southwest Petroleum University, Chengdu, Sichuan 610500, China Sichuan Province Key Laboratory of Natural Gas Geology, Chengdu, Sichuan 610500, China China National Offshore Oil Co. Ltd., Guangzhou, Guangdong 510240, China Exploration Department of Southwest Oil & Gas Field Company, PetroChina, Chengdu, Sichuan 610041, China Chuanqing Drilling Engineering Co. Ltd., CNPC, Chengdu, Sichuan 610051, China

针对陆表海台内浅滩单滩体规模小、储层厚度薄、非均质性强、平面分布具随机性、地震预测难度大等问题，以四川盆地自贡地区下三叠统嘉陵江组为例，采用岩芯观察、薄片鉴定、物性分析、压汞及测井等多种资料，开展了陆表海台内浅滩型储层基本特征及储层发育主控因素研究，认为陆表海台内浅滩型储层岩性、储集空间类型、孔喉结构及孔渗关系等均存在较大差异，储层非均质性强。指出了台内浅滩型储层为典型的相控型储层，储层发育受多因素联合控制，其中海平面多旋回的震荡变化决定了台内滩单个储集体厚度小、纵向上多期叠置的分布样式，而台地内部次一级微地貌差异决定了台内滩型储层在早期就具有较强的平面非均质性，同生期岩溶作用是台内浅滩型储层主要的溶蚀作用类型，云化作用极大地改善了储层储渗性能，构造破裂及埋藏溶蚀作用进一步优化了储层质量。

Compared with the large-scale bending distribution of a platform margin shoal, shoal within the epicontinental platform has various disadvantages. These are the small scale of a single shoal, thin reservoir thickness, strong reservoir heterogeneity, random horizontal distribution, and seismic prediction difficultly. In an attempt to solve these problems, the Lower Triassic Jialingjiang Formation of the Zigong area, Sichuan Basin, was used as study area. Drill core observation, slice identification, physical analysis, mercury injection, and well logging were employed to analyze the basic characteristics and main controlling factors of the shoal reservoir within the epicontinental sea platform. The results show significant differences in the reservoir lithology, types of reservoir spaces, pore-throat structures and properties of pore, and the permeability of shoal within the epicontinental carbonate platform, i.e., the reservoir sh ows strong heterogeneity. The study results point to a typical facies-controlled reservoir, of which the development is jointly influenced by several factors. The polycyclic oscillation of the sea level determines the distribution type of the thin reservoir thickness and the vertical multiphase superimposed shoal within the platform. The shoal reservoir within the platform has strong horizontal heterogeneity in the early stage, which is controlled by secondary superficial differences in the platform. Syngenetic karstification is the main dissolution type in the reservoir. Dolomitization could improve reservoir permeability effectively, and structure fractures and burial dissolution could optimize the reservoir quality.

10.11885/j.issn.16745086.2016.04.27.02