Study on the calculation of geothermal fluids recoverable quantity and the distribution law of karst geothermal reservoirs in Hebei Plain

Using geothermal reservoirs method, analytical method, statistical analysis method and numerical simulation method, the authors evaluated and compared the geothermal fluids recoverable quantity of layered geothermal reservoirs in Hebei Plain. Geothermal reservoirs method and analytical method are suitable for geothermal fields with low exploration degree without geothermal wells or with only a small number of geothermal wells and productivity test data, so the calculation precision is relatively low. Statistical analysis method and numerical simulation method are suitable for geothermal fields with high exploration degree and multiple years of development and monitoring data, so the results are reliable. The karst geothermal reservoirs have the characteristics of high temperature, easy recharge and good sustainability, and they mainly occur in the Paleozoic and Middle-Upper Proterozoic strata and are covered by the Cenozoic strata, which is conducive to the thermal accumulation and insulation of the reservoirs. Karst fissures are widely distributed in the uplift zone of the bedrock’ forming deep hot water reservoirs. These reservoirs may develop into geothermal fields with great development and utilization value, and are the major reservoirs for further geothermal exploration and development.