Distribution of geothermal resources in Eryuan County based on entropy weight TOPSIS and AHP‒TOPSIS methods

Abstract

Geothermal resources have a very broad development prospect owing to their clean nature; accurate evaluation of their potential is an important basis for the realization of fine zoning and large-scale efficient development. Here, a geothermal evaluation system is established based on reservoir, cap-rock, transportation-system, heat-source, and water-source data. The entropy weight Technique Order Preference by Similarity to an Ideal Solution (TOPSIS) and Analytic Hierarchy Process - Technique Order Preference by Similarity to an Ideal Solution (AHP-TOPSIS) methods are used to evaluate geothermal resources in Eryuan County, and the evaluation results are superimposed with equal weights, and combined with the Moran index, to determine the geothermal exploration potential. Our results show that geothermal resources in Eryuan County are abundant, being concentrated in Liantie Township, Qiaohou Town, junction of Sanying and Cibihu towns, and junction of Fengyu and Yousuo towns. The Moran index indicates that there is significant geothermal accumulation, with high geothermal values mainly distributed around the water system. Three types of geothermal models are established based on control factors. The first one is controlled by the combination of reservoir and cap rock, while the second one is controlled by heat source and the third one is controlled by the combination of reservoir and cap rock and heat source. The junctions of Sanying and Cibihu towns, and Fengyu and Yousuo towns, are evaluated to have high geothermal potential, and these may become the next favorable directions for geothermal exploration in Eryuan County.