Linking thermochronological data to transient geodynamic regimes; new insights from kinematic modeling and Monte Carlo sampling of thermal boundary conditions

SANCHEZ NASSIF FRANCISCO; GALLAGHER, K.; EZPELETA, M.; COLLO, G.; DÁVILA, FEDERICO M.; MORA ANDRES

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2021 vol. 105

0895-9811

It is common practice to assume values for basal heat flow or basal temperatures as a lower boundary conditionfor thermo-kinematic models of crustal tectonics. Here, we infer spatial and temporal variations of the paleobasaltemperature from integrated modelling of thermochronological ages, to relate the inferred variations tothe geodynamic setting. To this end, we consider the Argentine Precordillera as a natural laboratory, given thatits kinematic evolution is relatively well constrained and therefore, the focus can be placed on the variations ofits basal thermal state. By means of a simple Monte Carlo sampling approach with thermochronological data asconstraints, we infer the paleo-basal temperature history. This is compared to estimates posed by models existingin the literature concerning flat-slab subduction. Our results imply that, given the kinematic models used to datein the area, extremely low temperature gradients (