Espolones cuspidados ("cuspate forelands") de grava en la costa atlantica de Patagonia. Ejemplos de las puntas Bustamante y Dungeness (Argentina y Chile)

Abstract

In the Patagonia region the eustatic sea rise was produced 20000 years BP and some glacial valleys such as Magellan straight and rio Gallegos estuary were flooded. Tills were reworked by tides and waves, and several cuspate forelands (Bustamante and Dungeness points) were developed as a consequence. Although the growing patterns of these two points are different, It is possible to stablish some similarities about the accretion processes. At first the gravels can be carried from the cliffs until the points by continental drift currents along the atlantic coast. Secondly, some events which can carry gravels from the atlantic ocean to the coast occurred. The Dungeness point was produced mainly as a consequence of the continental drift currents. On the other hand, the Bustamante point was originated by the marine currents from the ocean to the continent