Karst in siliceous rocks: Pseudokarst landforms and caves in the quartz dyke of Pico Sacro (Boqueixon, Galicia) Karst en rocas silíceas: El paisaje y las cuevas pseudo-kársticas de la vena de cuarzo de Pico Sacro (Boqueixon, Galicia)

In spite of the siliceous composition of the quartz dyke that forms the Pico Sacro, typical pseudokarst landforms can be observed as incipient karren-type forms, cavettos, tafoni, flared walls and alveolar weathering, boulder caves and an impressive deep vertical shaft named A Cova do Pico. The pseudokarstic character of this landscape is defined by selective weathering along the joints and fracture planes of this quartz dyke.