川北阆中—南部地区大安寨段裂缝预测

Fracture prediction of Daanzhai member in Langzhong-Nanbu area,northern Sichuan

川北阆中—南部地区地质条件复杂,大安寨段储层薄且超致密,孔、洞、缝是油气的主要储渗空间,裂缝的发育程度是决定油气产能高低的主要因素。相邻井在同一套储层产能上差异极大,反映储集体具有强烈的非均质性,并主要受裂缝发育程度控制。裂缝发育程度的预测是寻找有效储集体的关键。该文利用岩石破裂接近程度、曲率法和地震道不连续性检测3种方法,综合岩心、测井、测试等资料进行裂缝预测,提高了前人仅在二维地震资料基础上所做相关工作的精度,并通过"权重"的大小来衡量裂缝的相对发育程度,对裂缝进行了定量化研究,为寻找有利的储层分布区块,最终进行井位部署提供了依据。

The geological condition in Langzhong-Nanbu area in northern Sichuan is complex.The reservoir of Daan-zhai member is thin and super tight with its pores,holes and fractures as main storage and permeation spaces.The development of the fractures is the main factors for controlling the reservoir productivity.The great differences in reservoir productivity among the adjacent wells in the same set of reservoir reflect that the reservoir heterogeneity is strong and it is mainly controlled by the development of fractures.Based on core,logging and oil testing,the method of rock fracturing approximation degree,curvature method and seismic trace discontinuity detection method are used to predict the fractures,and the accuracy of fracture prediction which is depended on the 2D seismic data is well enhanced.The quantitative study by using the weight value to judge the fracture development is carried out,which provides basis for seeking the favorable reservoir and deploying drilling site.