P-11

Alignment of dolines at the contact between marls and limestones. Circular doline 6 metres in diameter and 10 metres deep that takes advantage of the contact between sandy marls and recrystallized limestones and the 60 W fracture. On its North edge, where the stream collapses, the change of materials can be seen. Small chamber at the bottom, reached through a smaller lateral opening with a crossed trunk over a 2.5-metre-diameter tube. The chamber is x-shaped with small ramps of stones and blocks at the sides, becoming filled with humus and stones.

The dolines serve as sinkholes for the surface streams that run over the sandy marls, camouflaged by vegetation, to sink at the contact with the recrystallized limestones. The doline acts as a sinkhole for the surface stream.