Mesoscopic Structural Analysis of the Schist Enclaves in Oban Massif, South-Eastern Nigeria

The schist enclaves in Oban massif, south-eastern Nigeria are deformed predominantly in a brittle manner and contain a superfluity of mesoscopic structural features such as joints, conjugate shear fractures, foliation planes and mineral veins. The analysis of these structural elements using standard structural techniques and statistical tools reveals the presence of only four major sets of fracture (N-S, NE-SW, E-W and NNW-SSE/NW-SE) with the NNW-SSE (150°-160° from the north) being the most prominent. Mesoscopic structural geometry in the schists unravelled the presence of pure and simple shear deformation with a somewhat dominant simple shear component. The increase in the dip of foliation planes from the western flank towards the east across some of the schist enclaves suggests the existence of a regional fold system which may have its axis trending in a N-S direction. This study provides foundation knowledge to mineral exploration, groundwater and quarrying activities in this area as they are usually structure controlled.