鄂尔多斯盆地DJ区块深部煤储层地质-工程甜点测井评价技术  

Logging-based evaluation for geological-engineering sweet spots in deep coal reservoirs of the DJ block,Ordos Basin

作　　者：王舵 刘之的 王成旺 刘天定[5,6] 陈高杰 郝晋美[5,6] 孙博文 WANG Duo;LIU Zhidi;WANG Chengwang;LIU Tianding;CHEN Gaojie;HAO Jinmei;SUN Bowen(College of Petroleum Engineering,Xi’an Shiyou University,Xi’an,Shaanxi 710065,China;Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil&Gas Reservoirs,Xi’an,Shaanxi 710065,China;School of Earth Sciences and Engineering,Xi’an Shiyou University,Xi’an,Shaanxi 710065,China;Engineering Technology Research Institute of PetroChina Coalbed Methane Co.,Ltd,Xi’an,Shaanxi 710082,China;Research Institute of Exploration and Development,Changqing Oilfield Company,PetroChina,Xi’an,Shaanxi 710018,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil&Gas Fields,Xi’an,Shaanxi 710018,China)

机构地区：[1]西安石油大学石油工程学院,陕西西安710065 [2]陕西省油气田特种增产技术重点实验室,陕西西安710065 [3]西安石油大学地球科学与工程学院,陕西西安710065 [4]中石油煤层气有限责任公司工程技术研究院,陕西西安710082 [5]中国石油长庆油田公司勘探开发研究院,陕西西安710018 [6]低渗透油气田勘探开发国家工程实验室,陕西西安710018

出　　处：《石油与天然气地质》2024年第6期1772-1788,共17页Oil & Gas Geology

基　　金：中石油煤储层气科技项目(2022-GCYKJ-02);陕西省重点研发计划项目(2022GY-130)。

摘　　要：深部煤层气由于储层非均质性强、应力大、压力高和可改造性差,因此,其规模化开发要求对甜点开展精细评价。基于层次分析法(AHP法)提出了深部煤储层地质-工程甜点的12项评价指标,建立了测井评价模型,利用该模型对鄂尔多斯盆地DJ区块20余口井的深部煤储层甜点进行了评价。研究结果表明:①煤储层地质-工程甜点主控因素与产能施工压力比(I_(p))存在良好的相关性。DJ区块深部煤储层的上部甜点类别普遍优于中、下部,上部主要为Ⅰ类甜点,中部为Ⅲ类甜点,下部为Ⅱ类甜点。②含气量和脆性指数分别是储层及工程品质的主控因素。③煤储层顶、底板发育较厚的灰岩和泥岩,煤储层与灰岩和泥岩的力学特性差异较大,能有效封隔压裂缝在煤储层中扩展。压裂工况和试气结果表明所构建的地质-工程甜点测井评价方法应用效果良好,可用于深部煤储层压裂射孔选段和测井优选评价。The deep coal seams rich in coalbed methane(CBM)resources feature strong heterogeneity,high stress,high pressure,and challenging stimulation,rendering the accurate sweet spot evaluation crucial to the large-scale production of deep CBM.This study focuses on the logging-based evaluation of integrated geological-engineering sweet spots in deep coal seams,establishing an evaluation model with 12 evaluation indices using the analytic hierarchy process(AHP)method.Employing this model,we carry out sweet spot assessment of deep coal seams in over 20 wells in the DJ block.The results indicate that the major determinants of the geological-engineering sweet spots are strongly correlated with the ratio of a CBM well’s daily gas production to its construction pressure in the proppant transport stage(I_(p)).The upper part of deep coal seams in the DJ block generally exhibits superior sweet spots compared to its middle and lower counterparts.Specifically,the upper,middle-lower,and lower parts predominantly exhibit ClassⅠ,Ⅲ,andⅡsweet spots,respectively.Gas content and brittleness index are identified as the primary factors controlling high-quality reservoirs and engineering sweet spots.The coal seams’roofs and floors consist of thick limestones and mudstones,which exhibit significantly different mechanical properties from the coal seams and thus effectively block the propagation of induced fractures across the coal seams.The fracturing conditions and production test results indicate promising outcomes of the logging-based evaluation model.Therefore,this model can be applied to the logging-based selection and evaluation of the optimal perforation sections for the hydraulic fracturing of deep coal seams.

关 键 词：产能施工压力比 含气量 脆性指数 地质-工程一体化 甜点评价 深部煤储层气 鄂尔多斯盆地 

分 类 号：TE122.3[石油与天然气工程—油气勘探]