To clarify the vertical dominant reservoir and favorable exploration zone of No.8 coal seam in the Benxi Formation of the Yichuan-Shangzhenzi Block in the Yishan Slope of the Ordos Basin,the cores of No.8 coal seam in the Benxi Formation of the Yichuan Area were selected,and the sedimentary environment and coal-forming evo-lution characteristics of No.8 coal rock were comprehensively analyzed through experiments such as macro coal rock classification,microscopic component identification,major and trace element analysis.The results indicate that the No.8 coal rock of the Benxi Formation is the mixed accumulation product of bright coal,semi-bright coal,and dull coal.The organic components of the coal rock are mainly vitrinite,followed by inertinite.The inorganic components mainly consist of clay minerals such as kaolinite and illite-montmorillonite mixed layer,containing a small amount of quartz and feldspar.The middle and lower parts of the coal are rich in organic components,and the bright coal is well-developed,which constitutes a high-quality coal seam.The evolution degree of coal facies and coal rock is the main controlling factor of hydrocarbon accumulation,and the low water-covered forest swamp is the favorable explo-ration zone.This understanding is highly significant for the analysis of the enrichment law of No.8 coal seam in the Benxi Formation in the Yichuan area and has an excellent guiding significance for the exploration and development of coalbed methane.
关键词
煤层气/煤岩特征/成煤环境/煤岩组分/地球化学特征/鄂尔多斯盆地/宜川地区
Key words
coalbed methane/coal rock characteristics/coal-forming environment/coal rock composition/geochemi-cal characteristics/Ordos Basin/Yichuan Area
维普
万方数据