Early Paleozoic Structural Development in the Nw Argentine Basement of The Andes and Its Implication for Geodynamic Reconstruction
- Garry D. Mckenzie
Published Online: 21 MAR 2013
Copyright 1987 by the American Geophysical Union.
Gondwana Six: Structure, Tectonics, and Geophysics
How to Cite
Willner, A. P., Lottner, U. S. and Miller, H. (2013) Early Paleozoic Structural Development in the Nw Argentine Basement of The Andes and Its Implication for Geodynamic Reconstruction, in Gondwana Six: Structure, Tectonics, and Geophysics (ed G. D. Mckenzie), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM040p0229
- Published Online: 21 MAR 2013
- Published Print: 1 JAN 1987
Print ISBN: 9780875900643
Online ISBN: 9781118664483
Tectonometamorphic zones were defined within the lower Paleozoic basement of the NW Argentine Andes in a transitional zone between two Andean segments of different geotectonic evolution. In the Cambrian, the Pacific edge of Gondwana changed from a passive to an active continental margin. This event began with folding of a Vendian/Eocambrian sediment wedge (Puncoviscana Formation and equivalents). The effects can be traced progressively over all structural levels with exposed depth increasing from north to south. Phenomena of a second deformation are of different nature and age but mostly characterized by shear belts causing large-scale crustal imbrication. In the lower tectonic levels this phase coincides with subduction-related magmatism of Ordovician age. A flat subduction slab is supposed, somewhat steeper in the northern than in the southern segment. The following anatectic-granitic magmatism and weak deformation in the Devonian may have marked a new change to passive margin conditions.