Proceedings of the 12th International INQUA meeting on paleoseismology, active tectonic and archaeoseismology

32 PATA Days 2024 slip ratio (P/S), and the trishear angle (Allmendinger, 1998).Toenvisage themaximumpossible shortening accomplished by themodelled thrust, its tip point was located at the prolongation of the hanging wall height, where the possible contact between the layer deformed and the older one above was located. Also, we consider that the scarp morphology was very affected by erosional processes that highly degraded the original morphology. The minimum scenario was created with the morphology of the model closer to the current topography, together with a tip point propagated nearby above the surface or below. R E S U LT S At least six Quaternary surfaces of paired and unpaired alluvial terraces were identified at both sides of the La Escondida creek. Alluvial surface Q6 has been identified as the oldest morphostratigraphic unit, whereas the Q0 surface corresponds to the current streambed. These levels have been affected by different splays of LPTS, showcasing diagnostic and nondiagnostic fault scarps with associated monoclines. Fig. 2: Neotectonic map of the study area (1:6800). Morphostratigraphic Quaternary units are indicated with numbers. Main structures of the study area are represented with black and blue lines, being solid the ones observed at the field, dashed and dotted lines represent covered and inferred thrusts, respectively. Red lines indicate the location of where trishear models were applied. Radiocarbon and cosmogenic ages obtained by Schmidt et al. (2011a) are displayed with yellow stars. Two different Quaternary levels were chosen for shortening estimation due to the good preservation of their surfaces and the ages available (Schmidt et al., 2011a). The surfaces modeled with trishear were Q3 and Q4, located on the northern margin (Fig 2, 3). Both surfaces were affected by the same thrust in different topographic levels, and for each surface we have calculated maximum and minimum shortening rates, considering the dating errors (Fig. 3; Schmidt et al., 2011a).