Geological Conditions Of Coal Seam Gas Constituency Evaluation In East Yunnan

The area is a typical area of coal seam,high stress,complex structure,tectonic coal development,the current selection methods and indexes are common in this area is very difficult to use directly.Based on the former research results,with the development of Yunnan multi seam area as the research object and many coal bearing syncline and mining area as the basic research unit,combining with the experimental text analysis data,this paper analyzes the Geological controlling factors such as tectonic conditions,sedimentary characteristics and hydrological conditions in study area,discussing the geological characteristics of coalbed methane,such as coal bearing property,gas permeability,permeability and resource recovery.using “hierarchical optimization of key elements” and “the energy system of coal reservoir”,this paper optimize the coalbed methane favorable target area and “target area”,put forward a set of suitable for the study area over the CBM geological selection index system and method.Based on the above research results,with the geological resources of coalbed methane,the abundance of coalbed methane geological resources,the recoverable resources of coalbed methane,the abundance of recoverable resources of coalbed methane,geological resources above 1000 m,permeability,critical reservoir ratio as the key evaluation elements,using “hierarchical optimization of key elements”,this paper optimize the coalbed methane favorable target area of many coal bearing syncline(mining area)in Eastern Yunnan.Research shows that: Laochang is the most favorable area;En Hong,Agang,Guishan are more favorable area;Xinzhuang,Zhaotong as a general favorable area;Luomu,Tangtang,Baoshan,Laibin,Zhenxiong,Yangchang are unfavorable areas.Based on “the energy system of coal reservoir” for the Laochang and Enhong favorable target mining areas,characterizing quantitatively the effective migration system and effective pressure system of coal reservoir by the method of triprotic identification sign,this paper optimize the “target area” for coalbed methane exploration and development in Laochang and Enhong favorable target mining areas.The results show that the Ⅱ tectonic unit of Enhong mining area and the fourth prospecting area are the most favorable target areas.