Gypsum deposits in Iraq : an overview

الملخص EN

Gypsum deposits in Iraq are either primary or secondary in origin.

The primary deposits were deposited in different geological periods in semi restricted basins, of which, only the gypsum and anhydrite deposits of the Fatha and occasionally the Dhiban formations are exposed on the surface in the areas of Nineva, Kirkuk, Erbil, Sulaimaniyah, Diyala, Wasit and Anbar governorates, forming important resources for cement and plaster industries.

The total reserve of the primary gypsum is estimated to be 142 million tons.

The secondary gypsum deposits, present as gypcrete or gypsiferous soil, are developed in the upper few meters of the soil cover by different processes leading to enrichment of calcium sulfate in the soil, mainly by the upward migration of the sulfate-rich water by capillary action.

The gypsiferous soil is of low gypsum content in the depth of (0 – 25) cm and covers about 39% of Iraqi soil; while at the depth (25 – 150) cm it is of medium gypsum content and covers about 53% of the Iraqi soil.

The reserve of the gypsiferous soil is estimated to be 6 million tons.

Primary gypsum and gypsiferous soil have produced many problems in Iraq and are potential hazard to the constructions due to possible settlement of the foundations, as well as degrading the agricultural lands in reducing the productivity of the soils and limit the crop types.