Assessment of reservoir temperature of thermal springs of the northern areas of Pakistan by chemical and isotope geothermometry

摘要

Chemical and isotope geothermometers, i.e. the Na-K, K-Mg, quartz andδ~18O(SO_4-H_2O), have been applied to estimate the reservoir temperature of the thermal springs in the northern areas of Pakistan. The chemical types of the thermal waters and the effects of mixing of shallow cold water with the thermal end-members are discussed. These waters are neutral to slightly alkaline and have low dissolved contents. Sodium is the dominant cation in almost all the cases. In terms of anions, the hot waters of Budelas are of the SO_4 type, those of Tatta Pani are of mixed character(SO_4 and HCO_3), and the waters from the remaining areas show HCO_3 domination.