New fission-track age constraints on the exhumation of the central Santander Massif: Implications for the tectonic evolution of the Northern Andes, Colombia

The western flank of the central Santander Massif, shows a more complete thermal history along the Bucaramanga-Picacho profile, with the exposure of an exhumed zircon fission-track partial annealing zone. Thermal history modelling of zircon fission-track data of this profile shows that after burial and heating from about 150 Ma on cooling at rates of 7-10 °C/Myr started at about 25 Ma. For the lower part of the profile, the early Miocene ZFT ages indicate exhumation at rates of 0.3-0.5 km/Myr along the Bucaramanga fault, but were only about 0.1 km/Myr on the high plateau of the central Santander Massif.