The problems of environmental geology refer to the geologic phenomena, incidents or accidents arising from action of environmental geology. The action is mainly the mutual influence between human activity and geologic...The problems of environmental geology refer to the geologic phenomena, incidents or accidents arising from action of environmental geology. The action is mainly the mutual influence between human activity and geologic environment. When human activity is uncoordinated with objective laws of the geologic environment, the problems of environmental geology or economic loss would occur.Therefore,the level and the changing orientation of geologic environmental quality are relative to the types of human activity,particularly relative to human intentional-activities of geologic environmental exploitation project. The geologic environment fitting to mining may not fit to urban construction,and fitting to water conservancy and hydroelectric projects may not fit to communication,and so on.Economy evaluation on the profit and loss of geologic environmental quality is exactly to depict the level of the profit and loss of geologic environmental quality about geologic environmental exploitation projects and the展开更多
The Getang is a representative Carlin-type gold deposit in Southwest China.It has a proven reserve of about 30 tonnes at an average grade of 5.1 g/t Au.The orebodies occur as strat-abound lenses,and are structurally c...The Getang is a representative Carlin-type gold deposit in Southwest China.It has a proven reserve of about 30 tonnes at an average grade of 5.1 g/t Au.The orebodies occur as strat-abound lenses,and are structurally controlled by shallow NWW-and NE-trending fold-fault systems and the unconformity between the Upper and Middle Permian.In this study,the regional-and deposit-scale structural investigations,joints and finite strain measurements,and stress and dynamic analysis were conducted with an aim to reveal the structural process of the Getang gold deposit and clarify the relationship between the gold mineralization and structures.Three phases of deformation were identified in the deposit:(1)paleokarst was generated by a crustal uplift when the Youjiang Basin experienced extension at the end of the Middle Permian,laying the foundation for the unconformity;(2)the NW-trending structures were formed under a NNE-SSW compression during the Indochina-South China collision(Indosinian orogeny)in Triassic;(3)the NE-trending structures were generated or reactivated under a NW-SE-oriented compression during the Yanshanian intracontinental orogeny.The unconformity recorded two episodes of tectonic evolution in the NNE-SSW and NW-SE directions.Structural analyses and geochronology data suggest that the Getang gold deposit was formed as a result of tectonic transition from compression to extension during the Yanshanian intracontinental orogeny.展开更多
文摘The problems of environmental geology refer to the geologic phenomena, incidents or accidents arising from action of environmental geology. The action is mainly the mutual influence between human activity and geologic environment. When human activity is uncoordinated with objective laws of the geologic environment, the problems of environmental geology or economic loss would occur.Therefore,the level and the changing orientation of geologic environmental quality are relative to the types of human activity,particularly relative to human intentional-activities of geologic environmental exploitation project. The geologic environment fitting to mining may not fit to urban construction,and fitting to water conservancy and hydroelectric projects may not fit to communication,and so on.Economy evaluation on the profit and loss of geologic environmental quality is exactly to depict the level of the profit and loss of geologic environmental quality about geologic environmental exploitation projects and the
基金supported by the National Natural Science Foundation of China(Nos.42072091,41972206)the Hubei Provincial Natural Science Foundation Joint Project(No.2023AFD210)the China Geological Survey(Nos.12120115036201,DD20190443).
文摘The Getang is a representative Carlin-type gold deposit in Southwest China.It has a proven reserve of about 30 tonnes at an average grade of 5.1 g/t Au.The orebodies occur as strat-abound lenses,and are structurally controlled by shallow NWW-and NE-trending fold-fault systems and the unconformity between the Upper and Middle Permian.In this study,the regional-and deposit-scale structural investigations,joints and finite strain measurements,and stress and dynamic analysis were conducted with an aim to reveal the structural process of the Getang gold deposit and clarify the relationship between the gold mineralization and structures.Three phases of deformation were identified in the deposit:(1)paleokarst was generated by a crustal uplift when the Youjiang Basin experienced extension at the end of the Middle Permian,laying the foundation for the unconformity;(2)the NW-trending structures were formed under a NNE-SSW compression during the Indochina-South China collision(Indosinian orogeny)in Triassic;(3)the NE-trending structures were generated or reactivated under a NW-SE-oriented compression during the Yanshanian intracontinental orogeny.The unconformity recorded two episodes of tectonic evolution in the NNE-SSW and NW-SE directions.Structural analyses and geochronology data suggest that the Getang gold deposit was formed as a result of tectonic transition from compression to extension during the Yanshanian intracontinental orogeny.