Geophysical and geotechnical methods in subsoil evaluation at Magodo phase II Lagos, Nigeria

Abstract

Oyedepo Emmanuel Onyedika

The application of geophysical and geotechnical methods in subsoil investigation at Magodo phase II Lagos, Nigeria has revealed the presence of five subsurface geo-electric layers. This consists of topsoil, sandy clay, sand, clay and sand. The sand ranges in thickness from 14.33 to 37.3 m while the depth to the sand body varies from 3.35 to over 70 m. The clay layer ranges in depth from 22.4 to 43.89 m while its thickness varies from 27.64 to 55.89 m. The 2-D resistivity profiles revealed the lateral variation of the subsurface litho-logy with depth. Also the cone penetrometer test (CPT) shows competent values for penetrative resistance at 14 to over 18 m. The study shows that shallow foundation is feasible in some part of the study area. The results of the two methods correlate well with each other.