摘要
2015年以来,中国页岩气勘探开发取得重大进展,建成涪陵和威远2个国家级页岩气示范区,年产能超过70×108 m3。但在勘探开发过程中逐渐暴露出区块之间气井产能、压裂液返排率差异性大等问题。针对上述问题,根据岩心观察描述、分析化验资料以及测井解释成果,从储层沉积环境、厚度、矿物组成以及储集空间类型、物性、含气性等特征入手对比储层特征差异性。研究表明,涪陵和威远地区龙马溪组页岩储层各项指标与国外典型产气页岩储层相似,具有页岩气商业建产的储层基础。但与涪陵地区相比,威远地区存在储层厚度略薄,碳酸盐矿物组成含量高,相对富黏土矿物,有机碳含量、有机质孔占比、层理缝发育程度、孔隙度、水平渗透率、实测含气量等低的特征。探讨上述页岩储层特征差异性有利于解释两个地区页岩气藏勘探开发中所遇到的诸多问题,提出不同的压裂开采对策。
Significant progress has been made in shale gas exploration and development in China since2015.Two national shale gas demonstration areas,the Fuling and Weiyuan Shale Gas Fields have been built with the annual production capacity of more than 70×108 m3.However,problems were induced during the exploration and development,for instance,huge differences existed in productivity and fracturing fluids flow back rate between blocks.In allusion to the above problems,based on the description of core data observation,analysis data,and the result of logging interpretation,as well as the reservoir sedimentary environment,thickness,mineral composition and reservoir space type,its physical property and oil-bearing property,the difference of reservoir characteristics were contrasted.The result showed that each of the parameters of shale reservoirs in Longmaxi Formation of Fuling and Weiyuan Areas were similar with typical shale reservoirs abroad,they had the foundation for commercial gas production.Compared with Fuling Area,Longmaxi Area was characterized by thin reservoir,high content of carbonate minerals,relatively rich of clay minerals,low organic mass fraction,low porous ratio of organic mass,low level of bedding fracture development,low porosity and low horizontal permeability and low measured gas content.The study of the difference of shale gas reservoirs is favorable for interpreting the problems induced in shale gas exploration and development for the purpose of preparing the countermeasures for different fracturing operations.
出处
《长江大学学报（自科版）（中旬）》
2016年第6期1-7,75,共7页
Journal of Yangtze University(Nature Science Edition)
基金
国家"863"计划项目(2013AA064501)
国家科技重大专项(2011ZX05018002-001)
四川省科技计划项目(2015SZ0001)
关键词
龙马溪组
储层特征
差异性
页岩气
Longmaxi Formation
reservoir characteristics
difference
shale gas
