Chronology of Termination II and the Last Interglacial Period in North Spain based on stable isotope records of stalagmites from Cueva del Cobre (Palencia)
- Muñoz García, María Belén
- Martín Chivelet, Javier
- Rossi Nieto, Carlos
- Ford, Derek C.
- Schwarcz, Henry P.
ISSN: 1886-7995, 1698-6180
Year of publication: 2007
Volume: 33
Issue: 1
Pages: 17-30
Type: Article
More publications in: Journal of iberian geology: an international publication of earth sciences
Abstract
New insight into the timing and structure of the Last Interglacial Period (Eemian) was obtained through U-Th dating of four speleothems from Northern Spain and an analysis of their stable isotope records. The four stalagmites examined were collected from different levels of Cueva del Cobre, a cold high-mountain cave in the Cantabrian Ranges (N Spain), in which speleothem growth took place essentially during the warmer interestadials. Through 18 TIMS and ICPMS datings and 263 stable isotope analyses, the onset of the Eemian interglacial period was precisely dated at 150±2 ka, an age consistent with a few other palaeoclimatic records but notably... (Ver más) younger than the age ascribed by the Milankovitch theory. We also date the Eemian¿Weichselian transition (~115 ka) for the fi rst time in the Iberian Peninsula. U-Th ages revealed a consistent anomaly at ~105-100 ka BP, which could be related to a drastic environmental change during the MIS-5c interestadial. This event would have caused the resetting of the U-Th system at the base of the stalagmites during a short time interval. In addition, we propose a new simple geochemical test to ensure the lack of disturbance of this type of samples for dating purposes