摘要
在大量构造煤分析和鉴定的基础上 ,探讨了变形环境及不同性质应力作用对构造煤结构的影响。根据构造煤结构特征及其形成的环境条件 ,将构造煤分为碎裂煤和糜棱煤两大系列及初碎裂煤、碎裂煤、碎斑煤、碎粒煤、鳞片煤、揉皱煤和糜棱煤七种类型。指出碎裂煤系列是脆性变形环境中的产物 ,以裂隙发育和颗粒的破碎为主要特征 ;而糜棱煤系列则是以塑性变形为主 ,可以出现似变形纹、眼球构造和似“碎斑系”等特征构造 ,并具有脆性变形的叠加。对各类型构造煤的储层物性进行了初步探讨 ,初碎裂煤和碎裂煤裂隙发育、连通性好、渗透率较高 ,是较好的储层类型 ;糜棱煤系列构造煤结构极为破碎、裂隙连通性差、渗透率低 ,不利于煤层气的开采 ;
The influence of the deformation environment and different stress action on tectonic coal structure is discussed on the basis of analyzing and identifying a large number of tectonic coal samples.According to the structural features and formation conditions of tectonic coals,they may be divided into two systems,i.e. cataclastic and mylonitic coal systems and seven types,i.e. initially cataclastic,cataclastic,porphyroclastic,granulated,squamate,wrinkly and mylonitic coal types.It is pointed out that the cataclastic coal system is mainly characterized by the development of fissures and the crash of grains,being formed in the environment of brittle deformation,but the mylonitic coal system is characterized by undulose-like extinction,augen atructure and mortar-like texture,being formed in the environment of plastic deformation and the superposition of brittle deformation.Through the investigation on the petropysical properties of various tectonic coals.it was considered that the initially cataclastic and cataclastic coals being of these characteristics,as developed fissures,good connectivity and high permeability,are fairly good reservoir;the mylonitic coal system is unfavourable to the exploitation of methane,being characterized by intensive crash,poor fissure connectivity and low permeability;and the porphyroclastic and granulated coals mediate between both the formers.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2004年第5期27-29,共3页
Natural Gas Industry
基金
国家自然科学基金资助项目 (4 0 172 0 5 8)
国家 973计划煤层气项目 0 4子项目 (2 0 0 2CB2 1170 4 )
关键词
储层
物性
焦煤
气体压力
破碎程度
Tectonic coal, Structure, Coal- formed gas, Petrophysical property
