Thick-skin orogen–foreland interactions and their controlling factors, Northern Andes of Colombia
S. Hermeston
M. Nemčok
10.6084/m9.figshare.3453374.v1
https://geolsoc.figshare.com/articles/dataset/Thick-skin_orogen_foreland_interactions_and_their_controlling_factors_Northern_Andes_of_Colombia/3453374
<p>The study draws from reflection seismic, <em>in-situ</em> stress and low-temperature geochronology data on the Eastern Cordillera–Llanos foreland basin system of Colombia, which is
an example of the retro-wedge of the orogen with an advancing subduction zone. The system was obliquely converging during
deposition of the Lower Oligocene–Lower Miocene Carbonera to recent Guayabo formations, recording it by the northeastward
depocentre shift in the proximal Llanos Basin. While the southern portion of the foreland did not flex and undergo flexural
normal faulting after Carbonera deposition, the northern portion did. The earthquake data indicate that the northern Eastern
Cordillera undergoes strengthening by internal deformation, while the southern segment is already strong enough to undergo
significant displacements dominantly along its bounding fault systems. Furthermore, the southern segment initiated detachment
of the first thick-skin blocks from the proximal Llanos Basin. Such co-existence of different convergence maturity stages
along the orogen strike allows unravelling of its development starting with internal deformation and foreland flexure, followed
by mountain building and large-scale boundary fault displacements, to the large-scale foreland deformation. The onset of new
foreland accretion seems to be controlled by the resistance of the foreland plate to flexing, given that the orogenic engine
continues to drive convergence.
</p>
2016-06-21 11:21:45
orogen
deformation
convergence maturity stages
boundary fault displacements
Llanos Basin
northeastward depocentre shift
foreland
Geology