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...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 are 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.展开更多
Along with the continuously go deep into of the research on coal series stratum,unconventional coalderived gas gets more attention,including coalbed methane,shale gas and tight sandstone gas.However,selection evaluati...Along with the continuously go deep into of the research on coal series stratum,unconventional coalderived gas gets more attention,including coalbed methane,shale gas and tight sandstone gas.However,selection evaluation as the basis and prerequisite for the exploration and development of unconventional coal-derived gas has great significance.The purpose of this paper is to set up a selection evaluation system,and this system is called selection evaluation on co-mining of“the three gas”in coal series stratum.If a basin exists these three gases at the same time,then we can use this evaluation system to evaluate this type of basin and choose dessert area,finally,for co-mining of“the three gas”in coal series stratum provide guidance.By choosing the main control factors of coalbed methane,shale gas and tight sandstone gas,and based on fuzzy mathematics,analytic hierarchy process theory and multilevel fuzzy comprehensive evaluation theory to research selection evaluation system on co-mining of“the three gas”in coal series stratum.Finally,26 main control factors are selected,and then the index system is set up;in addition,by calculating the weight and establishing the membership function and evaluation set,and then selection evaluation system on co-mining of“the three gas”in coal series stratum with a four layer index is established.This paper can provide a theoretical basis and engineering guidance for unconventional gas exploration and development.展开更多
基金Supported by the PetroChina Science and Technology Major Project(2021DJ2101).
文摘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 are 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.
文摘Along with the continuously go deep into of the research on coal series stratum,unconventional coalderived gas gets more attention,including coalbed methane,shale gas and tight sandstone gas.However,selection evaluation as the basis and prerequisite for the exploration and development of unconventional coal-derived gas has great significance.The purpose of this paper is to set up a selection evaluation system,and this system is called selection evaluation on co-mining of“the three gas”in coal series stratum.If a basin exists these three gases at the same time,then we can use this evaluation system to evaluate this type of basin and choose dessert area,finally,for co-mining of“the three gas”in coal series stratum provide guidance.By choosing the main control factors of coalbed methane,shale gas and tight sandstone gas,and based on fuzzy mathematics,analytic hierarchy process theory and multilevel fuzzy comprehensive evaluation theory to research selection evaluation system on co-mining of“the three gas”in coal series stratum.Finally,26 main control factors are selected,and then the index system is set up;in addition,by calculating the weight and establishing the membership function and evaluation set,and then selection evaluation system on co-mining of“the three gas”in coal series stratum with a four layer index is established.This paper can provide a theoretical basis and engineering guidance for unconventional gas exploration and development.
