摘要
煤岩的变质程度影响着煤层的储集空间特征,对煤岩的孔隙度,渗透率以及煤岩微裂缝的发育都有重要影响。为了研究两者的关系,选取山西沁水盆地南部不同矿区有代表性的3号煤层,对不同变质程度煤样的镜质体反射率(R0)、孔隙度、渗透率进行了测试并对煤储集空间类型和结构进行扫描电镜观察。研究结果表明:3号煤层储集空间类型主要为孔隙和微裂缝;当R0小于2.4%,孔隙度、渗透率与R0呈负相关,R0大于2.4%时,孔隙度、渗透率与R0呈正相关,R0为2.4%可能是煤岩变质程度对煤岩孔隙度、渗透率影响的关键期,在高变质程度煤岩中孔隙度与渗透率的升高是由微裂缝的发育引起的,并且随着R0的增加,微裂缝发育程度增大。
The degree of coal metamorphism has influences on coal reservoir space characteristics and significantly impacted coal and rock porosity,permeability and development of micro-cracks.In order to study the relationship between them,a representative No.3 coal seam in different mining areas in the Qinshui Basin,Shanxi has been selected to carry out reflectance of vitrinite（R0）,porosity and permeability tests of coal samples with different degree of coal metamorphism,as well as the coal reservoir space type and structure scanning electron microscopic observations.The study result has demonstrated that： the reservoir space type of coal No.3 is mainly porosity and micro-crack.When R0 less than 2.4%,the porosity,permeability and R0 is negatively correlated,when larger than 2.4%,positively correlated,thus the R0=2.4% possibly represents the impact critical point of coal and rock metamorphic degree on porosity and permeability;the rising of porosity and permeability in highly metamorphosed coal and rock is brought about by micro-crack development,and micro-crack developing along with the increasing of R0.
出处
《中国煤炭地质》
2011年第11期31-35,共5页
Coal Geology of China
基金
中国地质大学(北京)团委大学生课外学术科技基金
地学院第8届学生课外学术科技创新项目资助
关键词
煤层
储集空间
变质程度
沁水盆地
coal seam
reservoir space
degree of metamorphism
Qinshui Basin
