Based on the data of outcrop,core,logging,gas testing,and experiments,the natural gas accumulation and aluminous rock mineralization integrated research was adopted to analyze the controlling factors of aluminous rock series effective reservoirs in the Ordos Basin,NW China,as well as the configuration of coal-measure source rocks and aluminous rock series reservoirs.A natural gas accumulation model was constructed to evaluate the gas exploration potential of aluminous rock series under coal seam in the basin.The effective reservoirs of aluminous rock series in the Ordos Basin is composed of honeycomb-shaped bauxites with porous residual pisolitic and detrital structures,with the diasporite content of greater than 80％and dissolved pores as the main storage space.The bauxite reservoirs are formed under a model that planation controls the material supply,karst paleogeomorphology controls diagenesis,and land surface leaching improves reservoir quality.The hot humid climate and sea level changes in the Late Carboniferous-Early Permian dominated the development of a typical coal-aluminum-iron three-stage stratigraphic structure.The natural gas generated by the extensive hydrocarbon generation of coal-measure source rocks was accumulated in aluminous rock series under the coal seam,indicating a model of hydrocarbon accumulation under the source.During the Upper Carboniferous-Lower Permian,the relatively low-lying area on the edge of an ancient land or island in the North China landmass was developed.The gas reservoirs of aluminous rock series,which are clustered at multiple points in lenticular shape,are important new natural gas exploration fields with great potential in the Upper Paleozoic of North China Craton.
关键词
鄂尔多斯盆地/石炭系本溪组/二叠系太原组/含铝岩系/煤-铝-铁三段式地层结构/源下成藏
Key words
Ordos Basin/Carboniferous Benxi Formation/Permian Taiyuan Formation/aluminous rock series/coal-aluminum-iron three-stage stratigraphic structure/hydrocarbon accumulation under source
维普
万方数据