New insights into mountain permafrost occurrence and characteristics in glacier forefields at high altitude through the application of 2D resistivity imaging

Investigation of permafrost in glacier forefields at high altitude in the Upper Engadine has been undertaken during recent years (1996-1998) using one-dimensional geoelectrical soundings as the standard geophysical technique to detect mountain permafrost. In summer 2002, two of the glacier forefields were revisited and two-dimensional electrical resistivity tomography applied at the same survey locations. The findings based on the interpretation of one-dimensional vertical geoelectrical soundings were confirmed by two-dimensional resistivity imaging. Furthermore, the application of electrical resistivity tomography provides more detailed insights into the occurrence and characteristics of permafrost in recently deglaciated glacier forefields as compared to the results obtained by traditional one-dimensional vertical soundings. Additionally, the more effective data acquisition enables new fields of application, which in turn will allow a more complete interpretation of the factors influencing the distribution of discontinuous and sporadic mountain permafrost. Copyright (C) 2004 John Wiley Sons, Ltd.