A PRELIMINARY SURVEY FOR TESTING OPERATIVITY AND EFFICIENCY OF GPR TECHNOLOGY BY MEANS OF UNSHIELDED ANTENNA FOR THE STUDY OF CALDERONE GLACIER, CENTRAL ITALY

Abstract

During July 2015 a survey using GPR technology was carried out over the Calderone Glacier in the Gran Sasso d’Italia Massif (highest peak 2912 m a.s.l.). The main aim of the survey was to verify the usability of bistatic unshielded antenna, uncoupled with the ground, and to assess GPR data quality vs reached depth. The use of this kind of antenna is suggested by the need to operate also over rough and irregular surfaces. The obtained results are to be considered very good, as they easily match with previous results obtained in 1992 and 1998 using GPR technology with a shielded antenna, coupled with ground. The interpretation of data highlights a good stability of the ice mass in the lowermiddle sector of the glacier, and a maximum ice thickness evaluated about 26 m. The choose system was a Radsys GPR with unshielded antenna of 150 MHz frequency, to cross an ice thickness lower than 30 m, as supposed by previous researches.