Fast Holocene uplift rates at the Andes of Chiloe, southern Chile

Seven ¹⁴C ages on shell material from elevated beaches in the Andes of Chiloe (42-43°S) indicate ages varying from 420 to 3130 yr BP. Estimated elevations of the sampled localities show that uplift of the order of 10 m/ka has affected the region. In this segment of the Andes, where amounts of coseismic uplift/subsidence of the order of 1 m were observed during the 1960 earthquake, the east-west distribution of the measured uplift rates is probably related to late Holocene coseismic deformation. Uncertainties concerning the contribution of postglacial isostatic rebound on paleo sea level and on the water depth at which the dated shells lived do not invalidate this conclusion. Uplift is probably related to the Liquine-Ofqui Fault Zone which crosses the area. -Authors