TY  - JOUR
A1  - Montero-Lopez, Carolina
A1  - Hongn, Fernando D.
A1  - Lopez Steinmetz, Romina L.
A1  - Aramayo, Alejandro
A1  - Pingel, Heiko
A1  - Strecker, Manfred
A1  - Cottle, John
A1  - Bianchi, Carlos
T1  - Development of an incipient Paleogene topography between the present-day Eastern Andean Plateau (Puna) and the Eastern Cordillera, southern Central Andes, NW Argentina
JF  - Basin research / publ. in conjunction with the European Association of Geoscientists & Engineers and the International Association of Sedimentologists
N2  - The structural and topographic evolution of orogenic plateaus is an important research topic because of its impact on atmospheric circulation patterns, the amount and distribution of rainfall, and resulting changes in surface processes. The Puna region in the north-western Argentina (between 13 degrees S and 27 degrees S) is part of the Andean Plateau, which is the world's second largest orogenic plateau. In order to investigate the deformational events responsible for the initial growth of this part of the Andean plateau, we carried out structural and stratigraphic investigations within the present-day transition zone between the northern Puna and the adjacent Eastern Cordillera to the east. This transition zone is characterized by ubiquitous exposures of continental middle Eocene redbeds of the Casa Grande Formation. Our structural mapping, together with a sedimentological analysis of these units and their relationships with the adjacent mountain ranges, has revealed growth structures and unconformities that are indicative of syntectonic deposition. These findings support the notion that tectonic shortening in this part of the Central Andes was already active during the middle Paleogene, and that early Cenozoic deformation in the region that now constitutes the Puna occurred in a spatially irregular manner. The patterns of Paleogene deformation and uplift along the eastern margin of the present-day plateau correspond to an approximately north-south oriented swath of reactivated basement heterogeneities (i.e. zones of mechanical weakness) stemming from regional Paleozoic mountain building that may have led to local concentration of deformation belts.
KW  - Andean Plateau
KW  - Eastern Cordillera
KW  - Eocene deformation
KW  - growth structures
KW  - northern Puna
KW  - north-western Argentina
KW  - southern Central Andes
Y1  - 2020
U6  - https://doi.org/10.1111/bre.12510
SN  - 0950-091X
SN  - 1365-2117
VL  - 33
IS  - 2
SP  - 1194
EP  - 1217
PB  - Wiley-Blackwell
CY  - Oxford
ER  -