Groundwater potentiality mapping of tertiary volcanic aquifer in IBB basin, Yemen by using remote sensing and GIS tools

Abstract

Groundwater (GW) is the primary source of water for local inhabitants in the Yemen Republic. The Yemen Republic is dominated by an arid and semi-arid climate and suffers from a scarcity of natural resources and a soaring population growth rate. The IBB basin is one of the areas of main concern in Yemen, as the ascending local inhabitant’s activities have led to an increase in the water demand throughout the IBB City (The major City of IBB basin area). The area is mainly covered by stratified volcanic rocks of Tertiary age. The current research aims to delineate, identify, integrate, assess and map the groundwater potentiality (GWP) zones in the Tertiary volcanic aquifer of the IBB basin, Yemen utilizing space-borne data and weighted overlay method in GIS tools. Thematic layers such as lithology, slope, plain curvature, structural lineaments density, geomorphology, land use/land cover, drainage density, and rainfall intensity were used as factors in the geo-database building of the GW potentiality map. To each class of the factor layers, a fixed score was assigned. The scores were ranked, and the weighted sum for all layers was calculated. Finally, a GW potentiality map of the IBB basin area was constructed by integrating the weighted thematic digital maps. The integrated model’s results were classified into three main categories; low, moderate, and high GWP. The model validity was tested by considering the geospatial relationship between the resulted recharge productive zones and the distribution of the real-life productive wells and springs of IBB basin area. The integrated results successively delineate the GW potential zones in the IBB basin and raise awareness to methods useful for the management of GW resources and water recovery plans.