Los espeleotemas de las cuevas de Ortigosa de Cameros (La Rioja): datos cronológicos y consideraciones paleoambientales

Abstract

Disequilibrium U/Th series and radiocarbon-AMS radiometric techniques on speleothemic deposits from the Ortigosa de Cameros Caves (La Rioja, Spain) have been applied. The obtained data indicate variable frequency climatic changes during Upper Pleistocene and Holocene times. Three speleothem growth stages (>400, 179-38 and 23-7 ky) which can be related to warm global isotopic periods (11-9, 5-3 and 1) have been differentiated. During the most recent stage another three phases of speleothem speleothem activity related to regional warm and little wet environmental conditions (Holocene Optimun, Little Optimun and 150 BP-present time) have been deduced