Characteristics of Geothermal Reservoirs and Utilization Direction of Geothermal Resources in Southeast Coastal Areas of China

Abstract

Based on geological condition such as regional geological setting, Stratigraphic distribution, this paper summarizes three types of thermal reservoirs in the coastal areas of Southeastern China: Paleozoic Karst fissure-type, Mesozoic granite fissure-type and Cenozoic sandstone or sandy conglomerate-type. Paleozoic carbonate rocks are widely distributed and most located in the upper Paleozoic, such as Huizhou. Mesozoic granite fissure reservoir is distributed among the southeast coastal areas, such as Zhangzhou, Fuzhou, Fengshun, Yangjiang and south part of Hainan province, whose distribution is mainly controlled by NE-trending faults. Cenozoic sandstone or sandy conglomerate strata is mainly distributed in Cenozoic basins, such as Zhangzhou basin, Fuzhou basin and Leiqiong basin and so on. The geothermal systems buried depth of 0-3000 meters are mainly of medium and low temperature convection type, the resources of which can be mainly for direct-use, such as space heating, greenhouse heating, bathing and swimming, and other aspects. The geothermal systems buried depth of 3000-6000 meters are mainly hot dry rock type, with temperature range 150-200°C, which is conductive to the construction of enhanced geothermal system (EGS). The high-temperature resources can be used for power generation, cooling and agricultural drying, etc.