Temperatura wód podziemnych i jej znaczenie w badaniach hydrogeologicznych

Groundwater temperature is the basic physical parameter that determines the state and energy measure of the physical system while being an important indicator of the status of groundwater and aquifers. This article presents considerations on the temperature of fresh groundwater of the active exchange zone and their importance for the recognition of hydrogeological conditions. Review of groundwater temperature results application to analyze groundwater recharge process, flow and depth of circulation has been presented. It has been showed also how the water temperature supports evaluation of the groundwater chemical composition changes, the extension of contaminants, the hydraulic conductivity evaluation and the application in groundwater flow modelling study. A wide range of temperature variation in shallow waters of up to 20.3°C has been demonstrated based on measurements in the Quaternary aquifer in the Wrocław City infiltration intake and deep waters from the Neogen aquifer. Up to a depth of 10-17 m, significant seasonal temperature changes with depth have been documented. It was recommended to establish a neutral depth for the correct interpretation of the groundwater thermal field. Opposite spring water from a deeper aquifer of Cretaceous formations in the Stołowe Mts. documented an almost constant temperature higher by 4.6°C from the average air temperature. This indicates the range of groundwater flow depth of 170m below the land surface. A simple formula based on the density value of the heat flux, taking into account the average air temperature proposal, allows to calculating the depth of water flow. The methodical conditions for temperature measuring and the depth of location of temperature recording probesas well as their limitations, have been identified.