吉木萨尔凹陷芦草沟组页岩油储层岩性识别方法

Lithology Identification Method for the Shale Oil Reservoir of Lucaogou Formation in Jimusar Depression

页岩油是非常规油气资源的重要组成部分,资源潜力巨大,是今后的油气资源接替领域之一。新疆吉木萨尔凹陷芦草沟组页岩油储层岩性复杂,多为过渡性岩类,纵向变化快呈薄互层状,岩性的准确识别成为储层评价的重点和难点。基于组成岩石的矿物成分含量和碎屑颗粒粒级对岩性的影响,利用岩心标定测井,总结不同岩性的测井响应特征,构造岩性敏感参数。在建立各类岩性交会图的基础上,利用曲线重构技术和逐步剥离方法进行岩性识别,采用自主研制的解释软件实现了岩性剖面连续识别。利用该方法对新井进行岩性识别,明确了有效储层的主要岩性特征和各砂组岩性的纵横向展布规律,通过与岩心薄片化验资料进行对比分析,岩性识别符合率达81.4%。该方法为研究区页岩油储层测井综合评价奠定了技术基础。

Shale oil is an important part of unconventional oil and gas resources,which has great potential and will be one of the replacement fields of oil and gas resources in the future.The lithology of the shale oil reservoir of Lucaogou formation in Jimusar sag of Xinjiang is complex,and most of them are transitional rocks.Based on the influence of mineral composition and grain size of detritus on lithology,the logging response characteristics and sensitive parameters of structural lithology of different lithology are summarized by using core calibration logging.On the basis of establishing various lithology intersection maps,lithology identification is carried out by using curve reconstruction technique and progressive stripping method,and lithology section continuous identification is realized by self-developed interpretation software.Using this method to identify the lithology of the new well,the main lithology characteristics of the effective reservoir and the vertical and horizontal distribution law of the lithology of each sand group are defined.The coincidence rate of lithology identification reaches 81.4%by comparing with the test data of thin section of core.This method has laid a solid technical foundation for comprehensive log evaluation of shale oil reservoirs in the study area.