Investigation and mapping of geological construction materials in parts of chemoga river sub basin, debre markos, Ethiopia.

Currently the demands of geomaterials are intensively increasing all over the country regarding to the expansions of towns for the consumption of engineering structures and buildings. Therefore, searching workable, serviceable and accessible geomaterials nearby areas is a vital subject to stabilize the inflation of geomaterials. The present research was carried out in the Chemoga river sub basin in the Southern direction of Debre Markos town, North Western Ethiopia. To meet out the objectives, detailed surface explorations were carried out through systematically selected travel lines (across the strike and along streams) to detect the different lithologic formations and the contacts; A number of representative rock samples were collected for visual interpretations; GPS reading and metallic meter were the materials used in the field to quantify stratigraphic units, bedding thickness and lamination the lithologic formations; The Brunton compass was used in the field to measure the orientation (dip direction, dip amount and strikes) of geological structures. Besides to this, related literatures were reviewed to have a general background on the subject matter. Basalt and Sandstone are the dominant lithogical units in the study area and have existed with about an average thickness of 500