Abstract
Geophysical investigation was performed on the topsoil of the Benin Formation in Eket Local Government Area in order to access the degree of top soil stability based on elastic constants (Young modulus, Shear modulus and Bulk modulus). The seismic refraction method employing P-wave and S-wave sources were used to generate seismic energies that propagated through the subsurface. A 12-channel seismograph with signal stacking ability was used together with high frequency (100 Hz) geophones on the top-soil. The geophone intervals were set to 5 m at all the locations. The results of the findings based on these parameters were Young’s Modulus (-40. 772 x 108 N/m2 to 16.1481 x 108 N/m2); Bulk Modulus (-0.7964 x 108 N/m2 to 7.6896 x 108 N/m2) and Shear Modulus (1.3751 x 108 N/m2 to 7.0209 x 108 N/m2). A reasonable thickness of the top layer is porous, swampy, air-filled and weak. Excavation and refilling of the top and weathered zone with resilient geomaterials should be effective, and vibration test be carried out to ascertain the degree of reinforcement.