EXPERIMENTAL GRAVITATION AND GEOPHYSICS

Seismic noise is the major obstacle to performing sensitive measuremen ts of the gravitational field on the ground. The INFN (Istituto Nazion ale di Fisica Nucleare) underground laboratory in Gran Sasso, L'Aquila (Italy), seems to be a favourable place from the environmental noise point of view. This paper describes briefly two, relatively low cost, gravity experiments that can be performed in the underground laborator y: c) A measurement of preferred-frame and preferred-location effects. b) A test of the equivalence principle. Preliminary experimental data of the seismic noise ape also presented.