Combined Seismic and Penetration Tests on the Planetary Analogue Site Mount Etna

Abstract

Within the frame of the major national research project ROBEX dealing with the robotic exploration of extreme environments, dynamic penetration tests combined with seismic tests have been conducted at an altitude of over 2,600 meters on Mt. Etna. Focus was placed on the assessment of the near-surface soil properties. A light dynamic sounding penetrometer with variable impact energy has been employed. Parallel to this, seismic data generated by a surface impact source were collected with geophones mounted on embedded spikes of different lengths. In addition to the performed in situ tests, samples of the volcanic soil were collected for classification and shear strength testing in the laboratory. The paper describes the experimental set-up and the deduced soil properties from the two types of in situ test. The results show the limits of available empirical relationships derived for routine geotechnical applications. After refinement, the methodology employed may be transferred to planetary missions.