Existent Features And Resource Assessment Of Coalbed Methane In Shandong Province

Synthetically apply CBM geology, coal geology, coal petrology, coal chemistry and other theories and disciplines, use data of drilling, logging, geological logging and core analysis, production and various experimental analysis etc to study the existence features of CBM and resource assessment of Huanghebei and its adjacent area in Shandong province.Study the features of coal reservoir stratum of Huanghebei coalfield, the results shows that:the CBM gas source rock of the study area is the coal seam of Taiyuan formation. The distribution characteristics are the section appears to upper thin, lower thick;the plane appears to eastern more and thin,western less and thick. Almost all kinds of coal types are included, but the main types are gas coal and gas-fat coal. The macrofeature of coal of Shanxi formation is most of types are dim type coal, sapropelic coal or humosapropeliccoal exists to varying degrees in part of coal seam of Taiyuan formation. In coal reservoir stratum of the study area, porosity and permeability is low, superficial area is large. But it can generate high permeability reservoir stratum because of later reconstruction.Study the existence features of CBM of Huanghebei coalfield, the results shows that: CBM is generally present in the coal seam in the form of three states:adsorbed gas, free gas and water soluble gas. The CBM of the study area mostly exists in micropore of coal seam with adsorption state. Deep well point in the study area dominated by CBM, but in the superficial part is nitrogen. The CBM content is gradually heighten from southeast to northwest in study area. And deeply discusses the influence of structural environment, the lithology of the roof and floor seam,magmatic rock, burial depth of coal seam and the thickness of bedrock overlying and hydrogeologic condition to CBM existence.Estimate the CBM resources of study area and evaluate selection, consequently confirm that the deep coalfield of Huanghebei and its northern area can be the target area that can be explored and developed in future.