NEW METHODS OF SITE INVESTIGATION FOR PLUTONIC ROCKS

A REPORT IS PRESENTED OF THE DEVELOPMENT BY THE LABORATOIRES DES PONTS ET CHAUSSEES OF NEW LOGGING PROBES AND THE ADVANTAGES WHICH THESE REPRESENT IN PROSPECTING FOR PLUTONIC ROCK DEPOSITS. IT CONCERNS SONIC, GAMMA - GAMMA, NEUTRON - NEUTRON AND THE SELECTIVE NATURAL RADIOACTIVITY PROBES.