Análisis de fracturas geológicas extraídas por teledetección en imágenes Landsat TM, ejemplo de la zona de Imilchil-Tounfite (Alto Atlas central, Marruecos)

Abstract

The use of remote sensing, in this research, can be summarized in mapping and statistical studies of lineaments on the satellites images of the Jurassic outcrops in the Imilchil-Tounfite area, Central High Atlas of Morocco. This is to apply various manual techniques for extracting lineaments from Landsat TM image. Analytical techniques used in this work are: the principal component analysis (PCA) applied to selective bands of the visible and infrared, which allows creating new images with better visual interpretation. Directional filters N0°, N45°, N90°, and N135° with a 5.5 matrix were used to enhance lineaments in the corresponding perpendicular directions, and therefore to obtain a good discrimination of those structures. Preliminary results highlight a dominant geological fracturing trending ENE/WSW with 52% of the total lineaments, a second fracture trending is WNW/ESE at 23%, a third fracture series trending NE/SW with 20% and finally, a minor series of fractures trending NW/SE with 5% of the total lineaments. Distribution and statistical relationship, between fractures and the affected surface on the one hand and the fracture length on the other hand, shows a network of well-structured fractures. The final lineament map constitutes a contribution to complete the geology and assisting the mining and hydrogeological prospection, in the Imilchil-Tounfite area.