- Steephead valley
A steephead valley, steephead or blind valley is a deep, narrow, flat bottomed valley with an abrupt ending. Such valleys arise in
limestone orkarst landscapes, where a layer of permeable rock lies above an impermeable substrate such asmarl . They are created by a stream flowing within the permeable rock and eroding it from within, until the rock above collapses opening up a steep narrow valley which is then further eroded by the stream running across the impermeable valley floor. At the head of the valley the stream emerges from the rock as a spring. Notable examples can be found in theJura region ofFrance , for example the Reculée de Baume atBaume-les-Messieurs and the Reculée d'Arbois with its head atLes Planches-près-Arbois and its exit atArbois .In
North America , blind valleys (apparently, the preferred American term) are found in theDriftless Area .
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