川东石炭系黄龙组层序地层划分及储层特征分析

The division of sequence stratigraphy and analysis of reservoir characteristics in Huanglong Formation of Carboniferous in east Sichuan area

1. 成都理工大学信息工程学院,四川成都 610059;2. 四川石油管理局地调处物探研究中心,四川成都 610212

College of Information Engineering, Cheng-du University of Technology, Chengdu 610059, China

利用高分辨率层序地层学方法对川东地区TMC气田某区块石炭系碳酸盐岩地层横剖面进行了高频层序划分,在此基础上对该区沉积微相特征与储层分布规律的关系进行了分析,对石炭系顶界的差异风化剥蚀现象进行了解释。应用碳酸盐岩岩石物理学的观点,分析了形成该区石炭系地层和储层速度特征的地质原因,即石炭系的块状高速特征是石炭系成岩作用强,白云岩化程度高,沉积岩性颗粒相对较粗,孔隙类型以溶孔、溶洞为主等地质特征的综合反映。该地区有效储层表现为块状高速特征中的若干相对低速(薄)条带。

This paper presents high-resolution sequence stratigraphy to divide the profile of Carboniferous carbonate layer where is located in TMC field in east Sichuan area. There are three wells with core observations. Based on the result, we analyses the characteristic of the depositional microfacies, the rule of reservoir distribution and interprets the phenomenon of different weathering. Furthermore, using the viewpoint of carbonate petrophysics, the geological factors, which lead to the velocity characteristic of the layer and reservoir, are analyzed. The characteristic of blocky and large velocity is the integrated result of the strong diagenetic activity, strong dolo-mization, coarse sediments, and pore type (vugular pore and hole).