地质论评2017，Vol.63Issue(5)：1401-1418,18.DOI:10.16509/j.georeview.2017.05.019
中国煤储层渗透率主控因素和煤层气开发对策
The Controlling Factors of Coalbed Reservoir Permeability and CBM Development Strategy in China
摘要
Abstract
Objectives:The permeability of coalbed reservoirs in China is generally 1 ～ 2 orders of magnitudes inferior to that of US,leading challenges in coalbed methane (CBM) development.In this paper,the controlling factors of coalbed reservoir permeability are discussed and CBM development strategy is proposed.Methods:Based on in-situ permeability data and related geological data from 33 areas/mine sites covering almost all sedimentary basins under CBM exploration and development,this paper carries out a comprehensive analysis of the main controlling factors of coal permeability.Results:The study shows that the permeability is controlled mainly by coal body structure,megascopic fracture and microscopic cleat/fracture density and cleat/fractue filling due to tectonic evolution and related fluid activities as well as by the in-situ stress.Complex coal body structure,highly filling status and high in-situ-stress,are the main factors leading the permeability to be low in sedimentary basins in China.Conclusions:Moderate tectonic deformation producing megascopic fracture enhances coal permeability and strong tectonic deformation is detrital to coal permeability.Mineral filling in cleat/fracture system and higy in-situ stress is detrital to permeability preservation.Based on logging interpretation,the mylonite coals should be screened out for fracturing operations in highly stressed situations.Due to highly filling status of cleat/fracture system in Carboniferous—Permian coals in northern China,the development and application of acidization-fracturing technology is a new and helpful direction.The in-situ stress amplitude and stress types are to be appropriately evaluated for fracturing design.Finally,due to high in-situ stress conditions,the drainage of CBM well should be controlled with a schedule of step-wise depressuring.关键词
煤层气/渗透率/煤阶/煤体结构/割理/裂隙/地应力/开发对策Key words
Coalbed methane/permeability/coal rank/coal structure/cleat/fracture density/in-situ stress/development strategy引用本文复制引用
康永尚,孙良忠,张兵,顾娇杨,叶建平,姜杉钰,王金,毛得雷..中国煤储层渗透率主控因素和煤层气开发对策[J].地质论评,2017,63(5):1401-1418,18.基金项目
本文为国家科技重大专项(编号:2016ZX05044)资助的成果.This study was financially supported by National Science and Technology Major Project (No.2016ZX05044). （编号:2016ZX05044）
