深层白垩系致密砂岩裂缝定性识别、参数建模与控制因素分析--以塔里木盆地库车坳陷克深地区白垩系巴什基奇克组储层为例

Research on qualitative identification,parameter modeling and control factors of cracks in deep Cretaceous tight sandstone:taking the Cretaceous Bashijiqike Formation reservoir in Keshen Area,Kuqa Depression,Tarim Basin as an example

为解决塔里木盆地库车坳陷克深地区不同泥浆体系的裂缝识别精度低、参数定量化难度大、有效性评价困难等问题,以研究区巴什基奇克组储集层为例,综合测井新技术、优化参数算法和筛选裂缝发育控制条件等,提出一套致密油气藏裂缝性储层测井识别及综合评价方法。首先,基于岩心刻度成像测井、软件偏心校正及声电成像识别裂缝等定性评价裂缝;其次,在处理裂缝参数的基础上,利用Techlog软件,以体积比率优化裂缝孔隙度和以缝的倾斜程度校正裂缝密度,实现裂缝参数定量评价;最后,分别从构造位置、岩性及现今最大主应力等方面,对致密砂岩储层裂缝发育程度和主控因素进行分析。结果表明,该套裂缝测井识别及综合评价方法效果好,与试油资料、地质情况吻合较好,为非常规致密油气藏勘探开发提供依据。

In order to promote the accuracy of low fracture identification,parameter quantification,and effectiveness evaluation under different mud systems in Keshen Area,Kuqa Depression,Tarim Basin,taking the Bashijiqike Formation reservoir in the study area as an example,comprehensiving new logging techniques,optimizing parameter algorithms and screening fracture development control conditions are employed.A set of methods for logging identification and comprehensive evaluation of fractured reservoirs in tight oil and gas reservoirs is proposed.First,based on the combination of core scale imaging logging,software eccentricity correction,and acoustic and electrical imaging to identify fractures,to qualitatively evaluate the fractures.Second,on the basis of dealing with fracture parameters,Techlog software is used to optimize fractures by volume ratio porosity,and fracture inclination are used to correct fracture density to achieve quantitative and fine evaluation of fracture parameters.Finally,we analyze the degree of fracture development and main controlling factors in tight sandstone reservoirs from the aspects of structural location,lithology,and current maximum principal stress.The results show that the method of fracture logging identification and comprehensive evaluation is effective,it is in good agreement with oil test data and geological conditions,providing basis for the exploration and development of unconventional tight oil and gas reservoirs.