4. The karst plain, the escarpment cliff and block falls José M. Calaforra
From this position detailed aspects of the surface karst landscape of Sorbas may be clearly observed, especially the extensive karst plain and the escarpment cliff sculpted on top of the gypsum, and the block falls that result from the destruction of its own cliff. The broad overlying plain is a result of the levelling that was produced by the introduction of alluvial fans above the gypsum once the basin had become terrestrial. After the erosion of this material, the process of dolina formation was initiated on the karst plain. Differential erosion developed between the hard and resistant gypsum, and the much softer underlying marls, which progressively increased the relief of the gypsum cliff. At the same time, parallel fractures originated through the gravitational instability that it started to produce. These processes caused the carving and fall of large gypsum blocks onto the slope. These are known as block falls.
Karst plain.
Longitudinal fracture on the margin
Escarpment and cliff (archive photo, Almería Speleoclub).
Escarpment and cliff (archive photo, Almería Speleoclub).
Longitudinal fractures on the margin of the escarpment that cause its retreat, detachment and fall of blocks into the barranco.
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