Evidence of intrapermafrost groundwater flow beneath an active rock glacier in the Swiss Alps

Abstract

AbstractTemperature measurements in borehole 2/1987 through rock glacier Murtèl Corvatsch revealed a very high mean heat flow of 150 mW/m2. Between 52 m and 56 m depth, seasonal variations are observed; above and underneath this zone temperatures have remained negative during the last 4 years. In addition, a zero curtain effect at the same depth hints at the existence of a water aquifer which is active mainly in summer. This phenomenon is interpreted as a talik at about 55 m depth. The permafrost may have a total thickness of approximately 100 m. The high heat flow is a result of the boundary conditions at the surface (mean annual temperature: −3 °C) and at the aquifer (at a depth of about 50 m), where the temperature is close to 0 °C.