Glossary of Karst and Cave Terms
1. The reverse of a blind valley, extending headwards into the foot of a calcareous massif. The upstream end is terminated by a cliff, frequently lunate, from whose base emerges a subterranean karst stream meandering across a flat, steep-sided valley below the resurgence . 2. A valley that begins abruptly and has no headwaters, having formed from and below the site of a spring .