A Joint Method Based on Geochemistry and Magnetotelluric Sounding for Exploring Geothermal Resources in Sedimentary Basins and Its Application

Abstract

The precise exploration of the characteristics of geothermal fields in sedimentary basins, such as the temperature and burial depth of their deep geothermal reservoirs, is of great significance for improving the probability of penetration and reducing exploration risks and development costs. This study proposed a joint exploration method combining magnetotelluric (MT) sounding and geothermometers. Using this method, this study estimated the geothermal reservoirs’ temperature and the circulation depth of geothermal water in the Xianxian geothermal field, a typical geothermal field in a large sedimentary basin in northern China, and prepared the temperature and depth maps of the geothermal reservoirs. The main results are as follows. First, the bedrock’s geothermal reservoirs with karst fissures in the Xianxian geothermal field have great potential for development. Among them, geothermal reservoirs in the Jixianian Wumishan formation have a top depth of 1100–1500 m and a thickness of 700–1700 m, and the geothermal reservoirs in the Jixianian Gaoyuzhuang formation have a top depth of 3700–4000 m and a maximum drilled thickness of 400 m. The geothermal reservoirs of the Xianxian geothermal field mainly have medium and low temperatures of 138–160 °C and the circulation depth of the geothermal water is 5873 m.

Quantifying Fracture Dynamics in Clean Energy: A Novel Fractal Perspective

“…This model incorporates four innovative fractal parameters (fracture fractal dimension DS, fracture tortuosity fractal dimension DT, fracture roughness parameter  , maximum fracture length lmax) to quantitatively characterize the fracture structure, applying the refined fractal theory to geothermal reservoir extraction under complex thermal-fluid-solid coupling. The key findings are as follows: (1) The fractal geothermal extraction model proposed in this study effectively characterizes the evolution of fracture network distribution, curvature, roughness, and length in geothermal projects. The model's computational results align closely with data from actual geothermal extraction engineering.…”

“…As a renewable energy source, geothermal energy, characterized by its stability, longevity, and renewability, is widely acknowledged as a crucial direction for future energy development. In recent years, the exploration and application of geothermal resources have garnered considerable attention and research both domestically and internationally [1][2][3]. Factors such as the geological-hydrological conditions of the geothermal reservoir, the depth of geothermal extraction, and parameters of the injection and production wells significantly influence the efficiency of heat extraction.…”

Seepage and Heat Transfer of Dominant Flow in Fractured Geothermal Reservoirs: A Review and Outlook

“…As shown by deep exploration in recent years, the karst geothermal reservoirs in the Jixianian Gaoyuzhuang Formation in North China have water yields of 25-110 m 3 /h and are characterized by high temperatures, high stress, and strong heterogeneity [8,20]. Under the action of compression and tectonism, deep karst geothermal reservoirs have spaces dominated by pores and fractures and generally have permeabilities of a few to tens of millidarcys, while parallel fractures with an aperture of 1 mm have permeabilities of hundreds of darcys [21][22][23]. Conservative tracer tests were conducted in typical geothermal fields in North China, such as Xiaotangshan in Beijing [24], Xiong'an New Area [25], Xianxian in Hebei [7,26], and Donglihu in Tianjin [27].…”