Abstract:
Widespread use of geothermal resources helps reduce the use of fossil fuels and the management of haze. There are rich geothermal resources on the northern foot of the Qinling Mountain, but the research work is slow and unevenly distributed. This paper outlines the natural geography of the northern foot of the Qinling Mountain, discusses the characteristics of regional geothermal carriers and structural units, describes the distribution at the depth of near-surface (20 m) and deep place (1500 m) as well as geothermal gradients and Geothermal flow value. According to the different characteristics, the geothermal fluid on the northern foot of the Qinling Mountain is divided into four sections, with a discussion given to the characteristics of each section. The authors analyzed geothermal resources on the northern foot of the Qinling Mountain:the main source of energy is the conduction of heat inside the earth, supplementary energy is thermal energy generated by the decay of radioactive elements in rocks in deep formations, and thermal energy is generated during the conversion of montmorillonite to illite and biodegradation of organic matter heat energy. The formation patterns of geothermal resources on the northern foot of the Qinling Mountain are divided into heat conduction type and thermal convection type:Heat conduction geothermal resources are widely distributed, and thermal convection geothermal resources are mainly distributed in areas where deep faults are directly connected with the surface and in the vicinity of the fault zone. The authors calculated the total heat stored in the geothermal unit using the volumetric method and the amount of geothermal resources that are difficult to be used at 4000 m as well as the amount of geothermal resources that can be utilized at 4000 m. The authors calculated the geothermal fluid resources of Wenshuigou in Baoji, Tangyu in Meixian, Tangyu in Lantian, Huaqing Pool and Dongda in Xi'an by using heat flow method. According to the law of geothermal resource occurrence in the study area, the authors divided the whole region into encouraged mining area of geothermal resources and maintained mining area, and pointed out the direction of geothermal resources utilization. The purpose of this paper is to promote the clean energy industry on the northern foot of Qinling Mountains in a timely manner and provide a theoretical basis for the scientific and long-term development of geothermal resources.