Grain size characteristics of dune sands of the Grand Erg Oriental (Algeria)

Koull, Naima; Benzaoui, Tidjani; Sebaa, Ahmed; Kherraze, Mohamed El-hafedh; Berroussi, Sami

Journal Algérien des Régions Arides
Volume 13, Numéro 1, Pages 10-16
2016-06-01

Grain Size Characteristics Of Dune Sands Of The Grand Erg Oriental (algeria)

Authors : Koull Naima . Benzaoui Tidjani . Sebaa Ahmed . Kherraze Mohamed El-hafedh . Berroussi Sami .

Abstract

The dunes of the Grand Erg Oriental sea occupy 120 000 km2, about 12% of the Algerian Sahara surface. The grand erg oriental is composed two-thirds of sand dunes. The dunes are represented mainly by the linear-type with a northwestern to southeastern orientation. The textural characteristics of the sand forming the dunes are bimodal with a modal class in the fine sand size (2 ф and 2,64ф), well sorted (sorting < 0.5), positively skewed and very platykurtic. The dune sands are dominated by the rounded and well-rounded grains. The very fine sands are less rounded than the fine and medium sand. The grain size distribution and roundness characteristics reflect the high textural maturity of the studied sediments.