Groundwater quality of Damm area, Saudi Arabia

الملخص EN

Damm area is situated in the southeast of Jeddah between Latitudes 20° 30' and 21°20'N; Longitudes 30° 15' and 40°00'E.

The investigated area includes the wadis : Hamda, Arana, Khurga, Raghama, Abyad, Shamma, Ad Damm and Al Diem.

A photogeologic map has been prepared and field controls were made.

The main rock units in the area are a complex of metamorphic and igneous rocks overlain by the Shumaysi and Khurma Formations.

Ter- tiary-Quaternary basalts are also occuring in the area.

The groundwater quality of the area is characterized by electrical conductivity (E.C.) rang- ing between 890 and 52,480 n-mohs/cm and total dissolved solids (TDS) ranging between 454 and 32,818 mg/1.

The ionic relationships reveal that Na* and Cl exhibit a positive linear corre- lation.

Caf * and SO^ are also related.

However, other ions are not correlated.

Stiff diagram shows similar shapes, and from the Trilinear diagram the dominant salts in the groundwater of the area are mainly NaCl and Ca, MgS04.

Specific utilizations for the groundwater in Damm area are also included in this paper.