大宁—吉县地区地应力特征及其对煤储层渗透性的影响  

The stress characteristics of the Daning-Jixian Area and its influence on the permeability of the coal reservoir

作　　者：姜波[1,2] 汪吉林[1,2] 屈争辉[1,2] 李长贵[1,2] 王琳琳[1,2] 李明[1,2] 刘杰刚[1,2] 

机构地区：[1]煤层气资源与成藏过程教育部重点实验室,江苏徐州221008 [2]中国矿业大学资源与地球科学学院,江苏徐州221116

出　　处：《地学前缘》2016年第3期17-23,共7页Earth Science Frontiers

基　　金：国家科技重大专项(2011ZX05034);国家自然科学基金重点项目(41430317)

摘　　要：大宁—吉县地区是中国煤层气开发的重点区域之一,现代地应力对煤储层渗透性具有关键的控制作用。文中以煤层气开发井测井曲线分析和计算为主要手段,探索了一套适合于煤储层的地应力评价方法与技术流程。研究表明,大宁—吉县地区的5~#煤储层的最大与最小水平主应力具有自东向西总体上呈低—高—低—高的波浪式变化趋势;垂向主应力总体上呈东低西高的变化趋势,但在中部构造较复杂区域递增的趋势减缓;5~#煤层总体处于转换深度以下,受垂向应力作用较为显著,处于拉张的应力环境,有利于煤层裂隙的张开和渗透率的升高;最大水平主应力与优势裂隙发育方向接近,有利于裂隙的张开,相应提高了煤储层的渗透率,最小主应力低和主应力差大的区域渗透率较高。The Daning - Jixian Area is one of the key areas of coalbed methane exploitation in China. The modern stress principally controls the coal reservoir permeability. This paper explored a stress evaluation method and technique process fitted for coal reservoir, based on the analysis and calculation of well log for coalbed methane exploitation. The study has revealed that the maximum and minimum horizontal principal stress of the 5~ coal seam has a general waving variation trend of low- high- low- high from the east to the west of the Daning- Jixian Area; The vertical principal stress has a general variation trend of low in East and high in West, but the increasing trend decreases in the middle area with complex geological structures. The 5~ coal seam is generally under the stress transition depth, and is significantly affected by the vertical principal stress, which is in favour of the stretch of coal seam fracture and the increase of permeability, as in a tension stress environment. The orientation of the maximum horizontal principal stress is close to the development direction of the dominant fracture, which benefits the stretch of the fracture and results in the improvement of the coal seam permeability. There is a higher permeahility in the areas of low minimum principal stress and of high principal stress difference.

关 键 词：大宁—吉县 地应力 煤储层 渗透率 

分 类 号：TE132.2[石油与天然气工程—油气勘探]