Sedimentological and hydrochemical characteristics of A1 lith sabkha, Saudi Arabia

Abstract EN

A1 Lith sabkha is one of the extensive sabkhas on the Red Sea coast.

This study investigates its sedimentological characteristics including the sedimentary structures, stratigraphy, and mineralogy.

It also covers the hydro-chemistry of both the groundwater and the pore water.

The sabkha deposit is mainly arenaceous, composed mainly of sand with clay lenses.

Carbonates and evaporites are present either as cementing material or as intergranular crystals.

Mineralogically, they exist in the form of aragonite, dolomite, calcite, gypsum, halite and/or anhydrite minerals.

The percentages of the carbonates and evaporites decrease from the sabkha center outwards and also decrease with depth.

The grqundwater is mainly of moderately hypersaline and highly hypersaline.

Slightly hypersaline and very saline water also exist in the southern section of the sabkha.

The Total Dissolved Salts (TDS) of the pore water decrease with depth and generally follow the variations present in the salinity maps.

When correlated with salinity, the measured ion concentrations, except those for Na+ and Cl", mark the four different types of the groundwater (very saline, slightly hypersaline, moderately hypersaline, and highly hypersaline).