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

FRANCISCO, SANCHEZ NASSIF; KERRY, GALLAGHER; MIGUEL, EZPELETA; GILDA, COLLO; FEDERICO, DAVILA; ANDRES, MORA

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2021 vol. 105

0895-9811

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