An integrated study of fill and deformation in the Andean intermontane basin of Nabón (Late Miocene), southern Ecuador

(U–Th)/He thermochronometric constraints on the late Miocene–Pliocene tectonic development of the northern Cordillera Real and the Interandean Depression, Ecuador

“…Lavas and minor tuffs from the Santa Isabel Formation yield zircon FT ages (Hungerbühler et al, 2002) and K/Ar ages (Kennerly, 1980) that range between 19.7G0.5 and 8.0G2.2 Ma. Pyroclastic rocks of the Tarqui Formation yield ages ranging between 8.8G0.4 Ma (K/Ar plagioclase; Lavenu et al, 1992) and 6.3G1 Ma (zircon FT; Hungerbühler et al, 1995), whereas the pyroclastic Salapa Formation yields a single age of 2.4G0.8 Ma (zircon FT; Hungerbühler et al, 2002). These ages suggest that volcanism may have been almost continuous throughout the Miocene and Pliocene and therefore affected the thermal history of the samples.…”

Cenozoic Evolution of Hinterland Basins in the Andes and Tibet

“…A lack of Paleogene fill in the hinterland of Ecuador suggests erosion or nondeposition prior to Neogene activation of disconnected basins. Although these relationships are compatible with an elevated pre-Neogene orogen, marine fossils indicate that some hinterland areas remained at low elevation until 15-10 Ma (Hungerb€ uhler et al, 1995(Hungerb€ uhler et al, , 2002. Most basins are bounded by strike-slip and reverse faults near potential pre-Cenozoic sutures, suggesting subsidence in transpressional settings involving possible fault reactivation (Hungerb€ uhler et al, 2002;Winkler et al, 2005).…”

Provenance of late Oligocene to quaternary sediments of the Ecuadorian Amazonian foreland basin as inferred from major and trace element geochemistry and Nd–Sr isotopic composition

“…The Interandean Depression appears as a synformal area filled with Pliocene and Quaternary volcanic and volcanosedimentary rocks (Lavenu et al, 1992;Hungerbuhler et al, 1995Hungerbuhler et al, , 2002Winkler et al, 2005). The basement of the Interandean Depression is poorly known, but gravity data suggest a basement comparable to the Eastern Cordillera (Feininger and Seguin, 1983).…”