The Recharge Characteristics in the Highly Geothermal Potential Area, Tatun Volcano Group, Taiwan

Abstract

It has been long recognized that the Tatun Volcano Group is the most promising geothermal energy potential area, Taiwan. However, little attention has been paid in supply of water in terms of geothermal operations. This study provides a preliminary result from two adjacent catchments, South Sulfur and North Sulfur creeks, by analyzing geochemistry and water levels of surface water and shallow groundwater to learn the recharge characteristics of the region. Two groups, Ca-Mg HCO3 and Ca-Mg SO4, in both the surface water and shallow groundwater are identified by Piper Diagrams. It seems that groundwater reservoirs are affected by the precipitation exceed 500mm differently, 5-6 months for the South Sulfur and 3-4 months for the North Sulfur Creek catchments., HCO3-, SO42-, Ca2+ and Mg2+ are the most closely related to the variations of precipitation and could be used as indicators for further investigations.