Geology and Hydrogeochemistry of Al-Quwayiyah Area, Saudi Arabia PDF

Keywords

Saudi Arabia, geology, rocks

Abstract

Geological and hydrogeochemical studies were carried out on 60 km2 in Al-Quwayiyah area that consists mainly of igneous and metamorphic rocks. The former group includes extrusive and intrusive rocks of different ages and assorted compositions ranging from calc-calkaline to strongly alkaline affinities. The latter sequence has, at least, four metamorphic phases containing foliated and non-foliated rocks of ortho and para origins. They have N-S strikes with eastern dip to vertical foliation. The area suffers major and minor structures and shear zones where some Phanerozoic sedimentary cover also occurs. Ten shallow hand-dug water wells exist in Wadi Al-Faydhiyah in Al-Quwayiyah zone with depths of 20-40 m. The groundwater is of a reasonably good quality for all uses, although its quality changes downstream due to the extensive pumping in the drought seasons and becomes more mineralized. Regional geology with cross sections and other shallow wells in different areas from this zone were studied for comparison