Structural mapping of coastal plain sands using engineering geophysical technique: Lagos Nigeria case study

A. A. Adepelumi, M. O. Olorunfemi, D. E. Falebita, O.G. Bayowa

Department of Earth Sciences, Ladoke Akintola University, Ogbomoso, Nigeria..
Department of Geology, Obafemi Awolowo University, Ile-Ife, Nigeria.

DOI: 10.4236/ns.2009.11002                

Abstract

An engineering geological survey using the cone penetrometer and finite element method was carried out to characterize sand-fill thick- nesses in a reclaimed area of Lagos, SW Nigeria. A previously developed finite element program was modified in order to allow for predicting the sand-fill thicknesses, and have an unders- tanding of the geomorphic shallow structures existing pre-sand-fill. The program was tested using the obtained cone penetrometer test re-sults from the Lekki-Peninsula area. The finite element predicted thicknesses show good cor-relation with the penetrometer obtained thicknesses. Six zones with thick sand-fill thick-nesses varying from 1.25 to 6.0m were identified from the isopach maps, these zones correlate with major/minor depression associated with river/stream channels and creeks. These are the main shallow geomorphic structural features present in the area pre-sand fill. The structural trends of the depressions are largely influenced by the oceanic fracture pattern.

Keywords

Sand-Fill; Finite Element; Nigeria; Pene- trometer; Depression

Conflicts of Interest

The authors declare no conflicts of interest.

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