TY  - JOUR
A1  - Eisermann, Jan Oliver
A1  - Göllner, Paul Leon
A1  - Riller, Ulrich
T1  - Orogen-scale transpression accounts for GPS velocities and kinematic partitioning in the Southern Andes
Y1  - 2021-08-19
VL  - 2
IS  - 1
JF  - Communications Earth & Environment
DO  - 10.1038/s43247-021-00241-4
PB  - Nature Publishing Group UK
N2  - The Southern Andes are regarded as a typical subduction orogen formed by oblique plate convergence. However, there is considerable uncertainty as to how deformation is kinematically partitioned in the upper plate. Here we use analogue experiments conducted in the MultiBox (Multifunctional analogue Box) apparatus to investigate dextral transpression in the Southern Andes between 34 °S and 42 °S. We find that transpression in our models is caused mainly by two prominent fault sets; transpression zone-parallel dextral oblique-slip thrust faults and sinistral oblique-slip reverse faults. The latter of these sets may be equivalent to northwest-striking faults which were believed to be pre-Andean in origin. We also model variable crustal strength in our experiments and find that stronger crust north of 37 °S and weaker crust to the south best reproduces the observed GPS velocity field. We propose that transpression in the Southern Andes is accommodated by distributed deformation rather than localized displacements on few margin-parallel faults.
N2  - Upper crustal transpression in the Southern Andes is mainly accommodated by widespread deformation on oblique-slip reverse and thrust faults, according to a comparison of scaled analogue models with the observed GPS velocity field and fault patterns.
UR  - http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/11318
ER  -