Characteristics Of Thermal Reservoir And Evaluation Of Geothermal Resources In The First Member Of Quantou Formation In Songyuan Area

Conventional fossil energy resources are limited and non-renewable.At the same time,a series of problems such as material pollution,harm to human health and greenhouse effect caused by its large-scale use.Therefore,people need to find and use green and clean new energy to reduce the greenhouse effect and protect the natural environment on which we live.As a renewable energy,geothermal energy has the advantages of large resource potential,low carbon emission and wide distribution.All countries in the world are accelerating the research and application related to geothermal energy.At present,geothermal energy is mainly used in power generation,heating,bathing and other applications.Songyuan area contains rich geothermal resources,and widely distributed,is a very important renewable resources in the study area.According to previous exploration and drilling data,the sandstone of the first member of Quantou Formation in Songyuan area is one of the main thermal reservoirs in this area with large thickness and sufficient water.For a long time,the unclear thermal reservoir characteristics and geothermal resources of the first member of Quantou Formation in this area have seriously hindered the development and utilization of local geothermal industry.Therefore,it is necessary to identify the thermal reservoir characteristics of the first member of Quantou Formation and evaluate the geothermal resources of the first member of Quantou Formation,so as to provide favorable scientific basis and theoretical support for rational and efficient development and maximum sustainable utilization of local geothermal resources.In this paper,based on the analysis of the existing data in the study area and the previous research results in the adjacent study area,the sand body distribution characteristics of the three layers of the first member of the Quantou Formation are predicted by well constrained impedance inversion combined with time-depth conversion.The numerical simulation software TOUGH2.0 is used to simulate the temperature field distribution of the upper,middle and lower parts of the first member of the Quantou Formation.The geothermal resources of the thermal reservoir of the Quantou Formation are estimated by the thermal storage method,and the study area is evaluated based on the national standard of'geothermal reservoir evaluation method'.On the basis of the above research,the favorable reservoir distribution in the study area is optimized.This study shows.(1)The geothermal energy formed in the study area is dominated by deep heat conduction and formation radioactive heat,The lithology of thermal reservoir is mainly feldspar sandstone and lithic feldspar sandstone,The lithology of thermal reservoir is mainly feldspar sandstone and lithic feldspar sandstone;(2)The sand body thickness of the upper part of Quantou Formation is between 25?59 m,the sand body thickness of the middle formation is between 1?155 m,and the sand body thickness of the lower formation is between 41?210 m;(3)The numerical simulation results show that the upper temperature range of the first member of Quantou Formation is 43?69?,and the average temperature is 59?;the temperature range in the middle of the first member of Quantou Formation is 55–73?,and the average temperature is 65.9?;the temperature range of the lower part of the first member of Quantou Formation was 75–78?,and the average temperature was 77.8?;(4)The total amount of geothermal resources is equivalent to 2.2×10¹¹t of standard coal,of which the total amount of recoverable geothermal resources is equivalent to 5.50×10¹⁰t of standard coal;(5)The two favorable reservoirs delineated are located in and around Dawa Town,northeast of the study area,and southwest of Songyuan City.