Research On Evaluation Of Geothermal Resources In Zhaozhou County

Under the background of Songliao Basin, this paper makes a deep analysis of regionaltectonic setting, fracture distributions and the identification of the heat formation mechanismin Zhaozhou, depending on the seismic and drilling data from extensive survey. It studies thegeothermal field distribution of the different layers at different depths, and then identifies theabnormal geothermal field distribution area. The3.5~4.8℃/100M geothermal gradientvalues and66~76MW/M2heat flow values show that Zhaozhou is a high geothermal fieldvalue area of Songliao Basin. According to the structural evolution and sedimentary history inZhaozhou, it analyzes the evolution process of heat reservoir sedimentary systems andidentifies sedimentary characteristics and sand body development conditions of the mainreservoir, making an analysis of lithology characteristics and physical property distributiondiscipline of heat reservoirs in the study area. Starting from the basin tectonic environment, adetailed analysis of geothermal water sources and supply conditions in Zhaozhou has beenmade; it also analyzes chemistry characteristics of each heat reservoirs and regulations fortheir change. Layers for evaluating the thermal water resources in study area can be dividedinto two sets of geothermal reservoir systems in vertical according to the distribution of theheat sources, geothermal reservoir and regional aquiclude layers, which provides help for thestudy on the geothermal reservoir genetic model of the geothermal reservoir, the productionand resource values calculation, the wellhead temperature calculation and comprehensiveevaluation of geothermal resources. Single well production prediction model has beenestablished. A study on getting parameters has completed and it gives a discussion on thecalculated results; it predicts the amount of resources in the area through the total amount ofresources prediction model. Wellhead temperature calculation model is established tocalculate the wellhead temperature of each well in the study area. It has finished the naturalproduction of the geothermal reservoir and the resource assessment.Finally, seven representative quantitative indicators are selected to participate in thecomprehensive evaluation of the resource layer and the study has shown that the whole studyarea belongs to the class III geothermal reservoir. The physical property is poor in the workarea and the permeability is generally low, but the total amount of resources is larger, theporosity of the target layer is also relatively high, especially Quan3Member and Quan4Member with developed fractures. And the temperature of target layers is relatively high. Byacidification, fracturing and other means, Zhaozhou, with certain potential for producing hotwater, is able to achieve its commercial value.