Читать книгу Mountaineering in the Moroccan High Atlas. Walks, climbs & scrambles over 3000M онлайн

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Although the High Atlas is predominantly Jurassic limestone, there are significant interruptions at the western end of the range, with volcanic andesites and rhyolites, particularly in the Toubkal region. These weathered volcanic rocks are very fractured and bedded together as loose masses. The visual result in the Toubkal massif is of jagged peaks and steep-sided valleys, with mostly grey masses of scree evident in the summer and early autumn when free of snow cover.

Small ancient glaciers may have existed in the higher cwms, but these have now receded. In fact, there are no glaciers in all of North Africa.

Moving east of the Tizi n-Tichka, rivers have cut down through the soft Permian-Triassic rock to produce deep gorges. Together with huge escarpments, terraced cliffs and flat-topped summits, they are typical of the region, particularly in the Ighil Mgoun and Jbel Maasker areas. Close observations on the summit ridge of Ighil Mgoun reveal many small sea-shell fossils.

Toubkal south cwm route, on the ridge above Tizi Toubkal (Route 24)