Target selection for mid-high temperature geothermal exploration based on AHP and PCA: A case study of Jiangxi Province, China

Abstract

Jiangxi Province is located in the tropical zone of mid-high temperature geothermal resources along the southeastern coast of China. Geothermal geological surveys, the exposed natural hot springs, the explored geothermal walls and the reported geothermal research results related to the potential of geothermal energy indicate the abundant geothermal resources and the high formation potential of mid-high temperature geothermal resources in Jiangxi Province. However, the research level of geothermal resources in this area is relatively low, the distribution of geothermal hotspots is uneven, and the specific resource distribution, geothermal temperature, and resource quantity are not well understood, so it is difficult to systematically carry out the mid-high geothermal development in this province. Therefore, we collect the data of the study area, established a multi-index evaluation model combining experience and data, and carried out the evaluation of geothermal resources advantageous target areas and the analysis of geothermal impact indicators. The main purpose of this study is to use analytic hierarchy process (AHP) and principal component analysis (PCA) to qualitatively and quantitatively evaluate the mid-high temperature geothermal resources of the Jiangxi Province, and also to propose a dual-method comparative evaluation model for the study of the mid-high geothermal target area. Based on the quantitative data from geological, hydrological and geophysical sources and the extensive experience of regional workers and geologists, by using the AHP and PCA, we divide the study area into 7 geothermal resource potential zones and 38 geothermal optimal target areas. It is determined that deep large faults are the most critical indicators affecting the distribution of geothermal resources in the study area, followed by the heat storage value of the silicon enthalpy equation and the magmatic rocks. This study is of great significance for geothermal research in similar areas, multi-index and multi-data model analysis, and accurate positioning of high-quality geothermal resource target areas. It also has important guiding significance for the follow-up development planning of geothermal resources the research area or further research on the geothermal target area.