Examples of architecture of reefal facies and related deposits in the Devonian of the Cantabrian Zone (NW Spain)

Abstract

The Devonian record of the Cantabrian Zone (NW SpainJ is formed of an alternation of siliciclastic and carbonate units, chicfly of shallow water origin, that were deposited on the North Gondwanan pasive margin prior to the onset of the Variscan orogeny (Carboniferous).The carbonate units range from a few tens to some two hundred metres in thickness and record deposition in carbonate platforms of mainly ramp type. They are relatively rich in reefal faunas in such a way that seven reefal episodes ol uneven importance. spanning from earliest Pragian to Famennian, have been distinguished. These reefal episodes consist of coral and stromatoporoid bioherms and biostromes with a local appearance of niud mounds.