Stress field and active faults in the orogenic front of the Andes in the Malargüe fold-and-thrust belt (35°–36°S)

MESCUA, J.F.; BARRIONUEVO, M.; GIAMBIAGI, L.; SURIANO, J.; SPAGNOTTO, S.; STAHLSCHMIDT, E.; DE LA CAL, H.; SOTO, J.L.; MAZZITELLI, M.

TECTONOPHYSICS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2019 vol. 766 p. 179 - 193

0040-1951

We integrate field and wellbore data to discuss the stress field in the frontal sector of the Malargüefold-and-thrust belt (Andes of Argentina). Surface observations indicate N-S thrusts and NW toWNW and ESE strike-slip faults are active in the study area. Inversion of fault kinematic indicators,combined with borehole breakout data and a mini-frac test within the study area, constrain theQuaternary to recent stress state, which is characterized by a subhorizontal, E-W oriented maximumstress, and by intermediate and minimum stresses with similar magnitudes that are locallyinterchanged, producing a setting in which reverse and strike-slip faults are alternatively active. Theimplications of the recognized structures for earthquake hazard are examined.