Jonas Didero TAKODJOU WAMBO¹, Sylvestre GANNO^1,, Aloysius AFAHNWIE NGAMBU², Emmanuel NOMO NEGUE¹, Joseph MVONDO ONDOA¹, Jean Paul NZENTI¹

Remote sensing and Geographical Information System (GIS) technology have opened a new era in the field of applied geology. In this study, combined field and remote sensing applications through the processing of the Landsat-7 Enhance Thematic Mapper Plus (ETM+) were used to monitor to geologic structures in Ngoura-Colomines area. This mapping approach led to the detection of 654 lineaments in which two main types have been distinguished. The type-I (15%) shows two main directions (NE-SW and NW-SE) and corresponds to large-scale or regional structures while type-II (85%) with dominant NE-SW-trends represents foliation trajectories. In addition, type-I lineaments are compatible with the Riedel fault system composed of P and P′ fractures oriented NE-SW and NNE-SSW respectively; E-W trending R fractures and R' fractures with NW-SE trends. Our findings provide the evidence of a polyphase ductile-brittle structures such as shear zone and faults. These structures constitute pathway for both mineralizing fluids and ground water circulation. Since several gold artisanal mines exist in Ngoura-Colomines area, the proposed mapping approach is an important guide for the identification of the structures that control the gold mineralisation in the area.

Landsat ETM+ images, Lineaments, Riedel fault system, Ngoura-colomines