La cova Negra : Pollença, Mallorca : presència de dunes fòssils dins una cavitat submarina

catalaPresentam la descripcio i topografia d'una important cavitat submarina situada al cap de Catalunya (peninsula de Formentor, Pollenqa). Es tracta d'una cova d'abrasio marina de 200 m de longitud i 24 m de fondaria maxirna, que conte al seu interior dunes fossils que conformen bona part de les parets i sotil de la gruta. Les eolianites devien de reblir quasi per cornplet la cova al llarg d'un cicle clirnatic fred, en el qual la mar havia sofert un proces de regressio i les platges acumulaven importants diposits que s'adossaven als penya-segats. Una posterior transgressio marina erosionaria bona part dels diposits eolico-rnarins. EnglishWe present the description and survey of an important submarine cave located at the Cap de Catalunya (Peninsula de Formentor, Pollenqa). It is a marine abrasion cave, 200 m in length and with 24 m maxirnum depth, which has in its interior fossil dunes which rnake up the larger part of its walls and roof. The eolianites almost completely filled the cave during a cold clirnatic cycle, when the sea-level rnust have suffered a regression and the beaches accumulated important deposits of sand which banked up against the cliffs. A posterior marine transgression eroded a good part of these eolian-rnarine deposits.