IDEAN   23403
INSTITUTO DE ESTUDIOS ANDINOS "DON PABLO GROEBER"
Unidad Ejecutora - UE
artículos
Título:
Kinematic analysis of a transtensional fault system: The Atuel depocenter of the Neuquén basin, southern Central Andes, Argentina
Autor/es:
BECHIS, F.; GIAMBIAGI, L.; GARCIA, V.; LANES, S.; CRISTALLINI, E.O.; TUNIK, M.
Revista:
JOURNAL OF STRUCTURAL GEOLOGY
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Año: 2010 p. 1 - 14
ISSN:
0191-8141
Resumen:
The Atuel depocenter of the Neuquén basin originated as an Upper Triassic to Lower Jurassic rift system,
later inverted during the Andean contractional deformation. In order to study the extensional architecture
and the kinematic evolution of this depocenter, we collected a large amount of field and subsurface
data, consisting of slip data from outcrop-scale normal faults, thickness and facies distribution
within the synrift deposits, and structural data from angular and progressive unconformities. The Atuel
depocenter has a NNW trend, showing a bimodal distribution of NNW and WNW major faults (first and
second order faults). On the other hand, from kinematic indicators measured on outcrop-scale faults
(third and fourth order faults), we found a mean NE internal extension direction, which is oblique to the
general trend of the sub-basin. Taking these particular characteristics into account, we interpreted the
Atuel depocenter as an oblique rift system. We evaluated two mechanisms in order to explain the
development of this transtensional system: 1) reactivation of upper-crustal NNW-oriented Paleozoic
shear zones, and 2) oblique stretching of a previous NNW-oriented lithospheric weakness zone.