Processes larger than 10000 years
Fault systems in the broken foreland of NW Argentina are associated with isolated seismicity, deformation, and uplift, and they pose a major problem in understanding the spatiotemporal characteristics of individual earthquakes and long-term deformation patterns. Range uplift in these environments is highly disparate in time and space, without a clear deformation front as in the foreland fold-and-thrust belt to the north. Some ranges constitute large anticlines that have formed over blind thrusts, such as the growing anticlines west of the town of Salta.
This project will investigate the primary source rocks for Sn (and Nb-Ta) and rare earth elements (REE) in the pre-Andean basement rocks (granites, pegmatites, metamorphic complexes) and the enrichment/mobilization processes related to chemical (hydrothermal alteration or weathering) and mechanical processes (ductile or brittle deformation in fractures and ductile shear zones). The investigation will focus on selected field occurrences of Palaeozoic granites, pegmatites, and their highly deformed metamorphic equivalents of the pre-Andean crustal basement, especially of the Salta Province.
The spatial architecture of sedimentary facies in a basin exert a fundamental control over the patterns of fluid flow and determines the regional distribution of possible reservoirs and seal units. The distribution of sedimentary facies can be predicted to some extent by sequence stratigraphic theories. These models offer a conceptual framework to extrapolate facies distribution at a regional scale in 2D, ranging from continental to basinal.
The Chaco-Paraná Basin is located east of the Sierras Pampeanas and the Santa Barbara System. The basin has been a depocenter since the early Paleozoic and has been under strong influence of the Andean orogeny since the Cenozoic. In the basin, a gradient of different deformation styles developed due to the Andean orogeny. This project aims to construct a data-consistent, integrated three-dimensional structural model of the Chaco-Paraná Basin on a lithospheric scale.
The Andean foreland demonstrates a pronounced N-S oriented differentiation in the style and magnitude of deformation and the nature of sedimentary basins. East of the Altiplano-Puna plateau and the Eastern Cordillera, a wedge-shaped, ~250-km-wide thin-skinned fold-and-thrust belt defines the eastern border of the orogen, which then transitions into the contiguous Chaco-Paraná foredeep.
The evolution of the inter-mountain Salta basin is related to the evolution of the Central Andes. An intracontinental rift was formed by extensional processes and subsequently filled by up to 5500 m sediments from the Neocomian to the Paleogene intercalated by minor volumes of magmatic rocks. This complex constitutes the Salta group. Paleoenvironmental analysis reveals depositional history controlled by tectonic and climatic changes.