In the frame of a co-operation between the Earth Science Department of the University of Modena and Reggio Emilia and the OGS, a geophysical investigation, including geo-electrical profiles and a 3D seismic acquisition, was detected in Nirano (Italy, Northern Apennine) where mud volcanoes are present. <br>The aim of the investigation was to determine the geometries of the shallower structures, across a mud volcano (Fig. 1), using information obtained by tomographic inversion of first arrivals of 3D seismic data and resistivity models obtained by 2D ERT (Earth resistivity Tomography) data. <br>The joint information from different geophysical methods furnished a detailed map of the structures of the first 30 - 50 m in depth, and the final results are in agreement. <br>