Hallazgo de dunas fósiles de final del pleistoceno en las Islas Murciélago, Costa Rica

Abstract

In this paper we described fossil dunes found at the Islas Murciélago, Área de Conservación Guanacaste, south of the Santa Elena Peninsula, on the northwest part of Costa Rica. Currently, this region is exposed to strong winds during the dry season (December to May), which produce coastal dunes. This process has been active at least since the Upper Pleistocene, as we propose with the finding of the fossil dunes in the area. These dunes have a maximum corrected age, based on a 14C radiometric dating, between 15 981 and 17 132 years before the present, which coincide with the Heinrich 1 event. This finding indicates a paleoclimate of the region as very dry and with very strong winds, related to the Heinrich 1 event after the Last Glacial Maximum, which was a dry period. The direction of the wind, based on the stratigraphy, was NE to SW and from the NNW to the SSE. These directions correspond with the present day winds