New constraints on Holocene uplift rates for the Baudo Mountain Range, northwestern Colombia

摘要

A beach deposit on the southern end of the Baudo Mountain Range, at an elevation of ～2.0 m above the backshore of the modern beach, was dated at ～2870 years using optically stimulated luminescence dating. The calculated average uplift rate necessary to raise this deposit is 0.7 mm/yr. This rate combines the long-term regional deformation associated with the subduction of the Nazca Plate under the South American Plate and the collision of the Choco Block microplate against the South American continent, as well as uplift from local faults. We propose that rapid emergence probably as several pulses, each involving decimeter scale coseismic uplift, is likely to have occurred to elevate the beach above the intertidal zone and offset destructive wave erosion.