Geothermochronological insights into the Sierra Nevada de Santa Marta: provenance and exhumation through U-Pb and Fission Track in zircon

New geo-thermochronological data from modern sediments of the Sierra Nevada de Santa Marta (SNSM), a prominent mountain range along the Caribbean-South America plate margin in northern Colombia is presented. We applied U-Pb and Fission Track analyses in detrital zircon to document the provenance, exhumation, the cooling histories across high (900-850 ºC) and intermediate temperatures (320-180 ºC). The Zircon Fission Track (ZFT) results show Cenozoic ages, predominantly between 65-15 Ma. Populations between 55 and 80 Ma come from regions with intermediate elevations of the river basins. In general, this is in agreement with the ancient history of exhumation through the ~300 °C isotherm in SNSM. These same data can be observed in its extension to the south, in the Cordillera Central (CC) in Colombia.  The youngest population, up to 35 Ma that occurs in SNSM, corresponds to sediment collected from elevations lower than 900 m and documents the accentuated exhumation resulting from the dismemberment and translation of the SNSM. This can be associated with transtension by the oblique convergence of the Caribbean plate. U-Pb results include Mesoproterozoic (1000-1500 Ma), Carboniferous (300-350 Ma), Jurassic (200-150 Ma), Triassic (250-200 Ma) and Upper-Cretaceous (100-70 Ma) populations. These results show a correlation with the basement, which is well marked during the Neoproterozoic and Jurassic. A spatial analysis by inverse methods including detrital ages and the spatial distribution of lithostratigraphic units is being developed to understand the spatial distribution of current denudation and its controls.