In addition to being among the major tiggers behind frequent earthquakes,fractures can allow surface water to infiltrate the permeable rocks,entering both shallow and deep aquifers.Occasionally,water penetrates to gre...In addition to being among the major tiggers behind frequent earthquakes,fractures can allow surface water to infiltrate the permeable rocks,entering both shallow and deep aquifers.Occasionally,water penetrates to great depths,heats up,and becomes geothermal water.Fractures similarly allow hydrothermal fluids to dissolve their chemical elements and form a mineral deposit.Given these important roles of fractures,this paper aims to map faults and fractures across the entire Moroccan territory in the form of lineaments extracted from remotely sensed images,and then analyze their spatial distribution using the fractal dimension(FD)approach,and then generate a fractal map of the entire Morocco as a guide for subsurface investigation purposes.It was found that the areas with high fractal dimension(FD˃1),considered potential groundwater recharge areas,essentially the northern Anti Atlas,the southwestern High Atlas,and the Meseta,present spatial conformity with several known mineral deposits,geothermal areas,and the epicenters of many historical earthquakes.This conformity can be a key element in expecting other unexplored mineral deposits,aquifers,or geothermal regions,as well as predicting the areas that may bear earthquake hazards in areas with high FD across the entire Moroccan territory.展开更多
Sinking columns are one of the most hazardous geological structures in north Chine typed coal fields. To understand the sinking column formation, to judge if the columns are hazardous or not, the inner circle mechanis...Sinking columns are one of the most hazardous geological structures in north Chine typed coal fields. To understand the sinking column formation, to judge if the columns are hazardous or not, the inner circle mechanism of groundwater in forming sinking columns in the relatively isolated areas was proposed according to the investigation on formation or distribution of sinking columns in some north China typed coal fields, such as Fengfeng, Xiangtai, Huaibei, Yangquan and so on. The heat generated by magma energized groundwater circulation and developed limestone karst in the relatively isolated areas. The CaCO3 solution accelerated by geothermal abnormality, the effect of high content of CO2 on dissolution and saturation of CaCO3 were discussed. Compared the forming conditions of the sinking columns developed in other coal mining areas in north China coal field, the paper deduced that the above factors collude karst development and sinking column formation, the columns in current geothermal areas are permeable and those in high coal rank areas or in paleo abnormally geothermal areas. The paper suggested that the sinking columns in the current abnormally geothermal areas were permeable, but those in the areas with high coal rank were not on contract.展开更多
With the rapid increase of energy demand and the increasingly highlighted environmental problems, clean, safe and widely distributed geothermal resources have become a hot spot for renewable resources development. The...With the rapid increase of energy demand and the increasingly highlighted environmental problems, clean, safe and widely distributed geothermal resources have become a hot spot for renewable resources development. The state of in-situ stress is a major control parameter for multiple links including well location, fracture inspiration and reservoir assessment, so how to determine the accurate state of in-situ stress in the deep thermal reservoir becomes a core problem drawing widely attention and urgent to be solved. Based on features of hot dry rock reservoir in terms of temperature and pressure and the comparison analysis, this article proposes the method of Anelastic Strain Recovery(ASR) as an effective method for determining the state of in-situ stress in the area with HDR resources distributed and explains the availability of ASR method by application examples.展开更多
文摘In addition to being among the major tiggers behind frequent earthquakes,fractures can allow surface water to infiltrate the permeable rocks,entering both shallow and deep aquifers.Occasionally,water penetrates to great depths,heats up,and becomes geothermal water.Fractures similarly allow hydrothermal fluids to dissolve their chemical elements and form a mineral deposit.Given these important roles of fractures,this paper aims to map faults and fractures across the entire Moroccan territory in the form of lineaments extracted from remotely sensed images,and then analyze their spatial distribution using the fractal dimension(FD)approach,and then generate a fractal map of the entire Morocco as a guide for subsurface investigation purposes.It was found that the areas with high fractal dimension(FD˃1),considered potential groundwater recharge areas,essentially the northern Anti Atlas,the southwestern High Atlas,and the Meseta,present spatial conformity with several known mineral deposits,geothermal areas,and the epicenters of many historical earthquakes.This conformity can be a key element in expecting other unexplored mineral deposits,aquifers,or geothermal regions,as well as predicting the areas that may bear earthquake hazards in areas with high FD across the entire Moroccan territory.
文摘Sinking columns are one of the most hazardous geological structures in north Chine typed coal fields. To understand the sinking column formation, to judge if the columns are hazardous or not, the inner circle mechanism of groundwater in forming sinking columns in the relatively isolated areas was proposed according to the investigation on formation or distribution of sinking columns in some north China typed coal fields, such as Fengfeng, Xiangtai, Huaibei, Yangquan and so on. The heat generated by magma energized groundwater circulation and developed limestone karst in the relatively isolated areas. The CaCO3 solution accelerated by geothermal abnormality, the effect of high content of CO2 on dissolution and saturation of CaCO3 were discussed. Compared the forming conditions of the sinking columns developed in other coal mining areas in north China coal field, the paper deduced that the above factors collude karst development and sinking column formation, the columns in current geothermal areas are permeable and those in high coal rank areas or in paleo abnormally geothermal areas. The paper suggested that the sinking columns in the current abnormally geothermal areas were permeable, but those in the areas with high coal rank were not on contract.
基金founded by Project of National Natural Science Foundation of China “Study on the Anelastic Strain Recovery Compliance in the In-situ Stress Measurement by ASR Method”, No 41404080the Project of Geological Survey “Survey on the In-situ Stress Field in Southern China”
文摘With the rapid increase of energy demand and the increasingly highlighted environmental problems, clean, safe and widely distributed geothermal resources have become a hot spot for renewable resources development. The state of in-situ stress is a major control parameter for multiple links including well location, fracture inspiration and reservoir assessment, so how to determine the accurate state of in-situ stress in the deep thermal reservoir becomes a core problem drawing widely attention and urgent to be solved. Based on features of hot dry rock reservoir in terms of temperature and pressure and the comparison analysis, this article proposes the method of Anelastic Strain Recovery(ASR) as an effective method for determining the state of in-situ stress in the area with HDR resources distributed and explains the availability of ASR method by application examples.
