Lithologic discrimination using selective image processing technique of landsat 7 data, Um Bogma Environs Westcentral Sinai, Egypt

الملخص EN

Um-Bogma area located in the westcentral part of Sinai, Egypt is covered by Precambrian basement rocks within the northern part of the Precambrian Arabian-Nubian crystalline massive.

Satellite images are among continuous sources of digital data for mapping lineaments and lithology.

In the present work, the lithologic discrimination and lineament analysis of Landsat-7 ETM+ data for Um Bogma area have been carried out using Geomatica PCI EASI/PACE (9.1) and GeoAnalyst PCI packages.

A selective image processing technique (SIPT) is a new approach in Geomatica, which gives rise to valuable results in this work.

The SIPT and the visual interpretation of the constructed Landsat false colour composite (FCC) and ratio images led to discriminate and delineate the lithologic rock units of the study area.

The structural lineament pattern for each interpreted lithologic unit has been constructed using SIPT.

The prepared rose diagrams for the extracted lineaments are very characteristic for each interpreted lithologic unit.

The structural lineament analyses and the discriminated lithologic units are integrated to show their relationships to the high radioactivity occurrences of the study area.

The NW-SE trend is the predominant regional structural lineament trend in the investigated area.

The NE-SW to the ENE-WSW directions is the predominant minor structural lineament trends.

The highest radioactivity zones of the study area are restricted to Um Bogma formation and the younger granitic rocks.