Distribution Characteristics And Development Potential Evaluation Of Geothermal Energy In Yinchuan Plain

The evaluation of the development potential of geothermal resources has always been a hot spot in the research of the geothermal industry,and it is a key part of the rational development and utilization of geothermal energy.The Yinchuan Plain contains abundant geothermal resources.The characteristics of the geothermal field are analyzed to determine the distribution of thermal storage resources and the range of each zone.The Monte Carlo variable analysis of heat storage parameters is used to evaluate the amount of geothermal resources,and the fuzzy comprehensive evaluation method combined with the analytic hierarchy process is used to evaluate the development potential of geothermal resources in each heat storage area of Yinchuan Plain,which provides a reference basis for the scientific exploitation and utilization of geothermal resources in the future.By investigating the geological data,geophysical prospecting information,geophysical characteristics and hydrogeological conditions of Yinchuan Plain,the characteristics of the geothermal field are analyzed.Through ground temperature monitoring,aquifer structure and lithological structure identification,the thermal reservoir distribution law of the Yinchuan Plain geothermal field is analyzed,combined with regional logging data,the thermal storage range of Yinchuan Plain is delineated,and the distribution characteristics of thermal storage resources are analyzed.The evaluation results show that:（1）Combining factors such as stratigraphic lithology,regional structural characteristics,and stratum thickness changes,determine the resource distribution characteristics of geothermal fields and 5 structural divisions:Western Slope Area,Central Deep Area,Eastern Slope Depression Area,Eastern Slope Rise Area and Southern Slope Area,and 4 thermal reservoirs:Neogene Ganhegou formation,Neogene Hongliugou formation,Paleogene Qingshuiying formation,Ordovician Majiagou formation.（2）Taking the western slope area as an example,Monte Carlo method variable analysis combined with triangular distribution calculation results show that random variables are identified through frequency analysis and triangular distribution method,and 75%of the thermal storage temperature frequency can be used as the optimal thermal storage temperature variable in the study area The standard deviation of the frequency and the calculation result of the heat storage method is only 4.21%.The evaluation results show that the total amount of geothermal resources in Yinchuan Plain is rated as 9.36×10¹⁷k J,the total exploitable geothermal resources is 2.32×10¹⁷k J,the total storage capacity of geothermal fluid is 1.54×10¹²k J,and the total exploitable geothermal fluid is 0.75×10¹¹k J.The total recoverable heat of the fluid is 5.76×10¹³k J,and the amount of conventional energy that can be replaced by the estimated total geothermal resources is 5.33×10⁸t/a standard coal.（3）Combined with the fuzzy evaluation index of thermal storage potential,the resource potential evaluation results of each thermal storage temperature zone in Yinchuan Plain and the corresponding reasonable development and utilization methods are clarified.Combined with the membership function,the fuzzy analytic hierarchy process is used to evaluate the potential of each thermal storage temperature zone.The heat storage resources are abundant in the temperature zones of 60～90℃:Ⅱ_2-1,Ⅱ_3-1,Ⅱ_3-2,Ⅲ₁,Ⅲ_3-2,Ⅲ_4-1,Ⅲ_5-2,Ⅳ₁,Ⅳ_4-2,Ⅳ₅,which can be developed and utilized Ways include:heating and cooling,medical treatment,hot spring bathing.Thermal storage zones with a temperature classification of 90～150℃:Ⅱ_2-2,Ⅲ_2-1,Ⅲ_3-1,Ⅳ_4-1,and the development and utilization methods include:power generation,drying,heating and cooling.Provide reference value for the development and utilization of geothermal resources in various thermal storage districts in Yinchuan Plain.There are 17 pictures,19 tables,and 94 references.