Yardangs in quartz-feldspar, reddened dune sands (Brava sands) south of Mogadishu, Somalia, have been produced by east-northeast winds transporting beach sand during the northeast monsoon dry season. The yardangs are developed obliquely in dune flanks sloping 10-20° to the south. Porites coral (82 ±6 ka) from the Ras Aw Maki calcarenite, deposited during marine isotope substage 5a, suggests that the easternmost Brava dunes, which appear to inter-finger or overlie it, are younger than 80 ka. The most important post-depositional change in the Brava sands that allowed yardangs to form was the addition of authigenic kaolinite clay by weathering of feldspars and hornblende.

Les yardangs des sables des dunes rubéfiées quartzo-feldspathiques (sables Brava) situées au sud de Mogadishu en Somalie, ont été produits par des vents de direction E-ENE qui transportent des sables de littoraux durant la saison sèche des moussons du nord-est. Les yardangs se développent de biais sur les versants des dunes, avec une pente de 10 à 20 degrés vers le sud. Des coraux Porites (82 ± 6 ka) de la formation calcariénite de Ras Aw Maki, déposés durant la sous-période marine isotopique 5a, suggèrent que la partie la plus orientale des dunes Brava, qui s'interpénètrent ou se superposent sur eux, ont moins de 80 ka. Le changement post-dépôt le plus remarquable dans les sables Brava, permettant la formation des yardangs, a été le rajout d'argiles kaolonites authigéniques suite à l'action du climat sur les feldspars et les hornblendes.

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