Using of Image Processing for a Multi-Spectral Bands Image to Specify the Rock Units in Gara Barran Anticline/ Duhok Northern Iraq

Abstract

A variety of image processing techniques were applied by the use of ENVI 5 program, on Landsat 7 ETM+ for a part of Bekhair anticline which is called Gara Barran anticline. It is located in the north of Duhok city, northern Iraq. Image processing methods were carried on (1, 2, 3, 4, 5, 7) image bands included: numerous false color combinations (RGB composites of three bands) were applied, and the best (741 RGB) was chosen. It was used as a base image for the two types of classification and geological mapping. It was comparted with a published geological map for the same area to indicate the name of the exposed geological formations in Gara Barran anticline which was identified at the field. Several image ratios were applied, and the best (2/3, 3/1, 2/5, 4/3, 5/7, 7/3 7/5) were chosen. In addition, the principal component analysis (PCA) (for all bands of Landsat7 image) was applied, only three of the resulted six components (PC3,PC4,PC5) were better and more useful than the other to discriminate some of the geological formations at Gara Barran anticline. Visual interpretation was applied on resulted images to identify the geological formation outcrops in Gara Barran anticline and the vegetation covered areas were also detected. Then all results were used to identify the exact training areas which were used in the supervised classification. Digital geological map was produced by the use of resulted images which were overlaid in Arc GIS 10.1 program and the transparency of the upper image was increased to 50%. By this way, the effect of vegetation cover was defeated then a digital geological map was exactly detected the geological formations with its contacts