A hydrogeological overview of the Upper Mega Aquifer System on the Arabian Platform

Abstract

With an extent of ~1,860,000 km², the Upper Mega Aquifer System on the Arabian Platform forms one of the largest aquifer systems of the world. It is built up by several bedrock aquifers (sandstone and karstified limestone aquifers), which are imperfectly hydraulically connected to each other. The principal aquifers are the Wasia-Biyadh sandstone aquifer, and the karstified Umm Er Radhuma and Dammam limestone aquifers. The stored groundwater is mainly fossil. Groundwater recharge took place in the geologic past under more humid climatic conditions. Due to the good water quality and high yield, the aquifers are intensively exploited, which has caused depletion of the groundwater resources. The presented qualitative and semi-quantitative description of the hydrogeology and the groundwater budget is the basis for integrated groundwater management of the aquifer system.