Reinterpretation of the Ordovician rotations in NW Argentina and Northern Chile: A consequence of the Precordillera collision?
Early Paleozoic paleomagnetic data from NW Argentina and Northern Chile have shown large systematic rotations within two domains: one composed of the Western Puna that yields very large (up to 80°) counter-clockwise rotations, and the other formed by the Famatina Ranges and the Eastern Puna that sho...
| Autores principales: | , |
|---|---|
| Publicado: |
2011
|
| Materias: | |
| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14373254_v100_n2_p603_Spagnuolo http://hdl.handle.net/20.500.12110/paper_14373254_v100_n2_p603_Spagnuolo |
| Aporte de: |
| id |
paper:paper_14373254_v100_n2_p603_Spagnuolo |
|---|---|
| record_format |
dspace |
| spelling |
paper:paper_14373254_v100_n2_p603_Spagnuolo2023-06-08T16:15:44Z Reinterpretation of the Ordovician rotations in NW Argentina and Northern Chile: A consequence of the Precordillera collision? Spagnuolo, Cecilia Mariel Rapalini, Augusto Ernesto Block rotations Gondwana NW Argentina Paleomagnetism Paleozoic block rotation collision zone crustal shortening kinematics microplate Ordovician paleomagnetism Paleozoic shear zone Anatolia Argentina Chile La Rioja [Argentina] Sierra de Famatina Sierras Pampeanas Turkey Early Paleozoic paleomagnetic data from NW Argentina and Northern Chile have shown large systematic rotations within two domains: one composed of the Western Puna that yields very large (up to 80°) counter-clockwise rotations, and the other formed by the Famatina Ranges and the Eastern Puna that shows (~40°) clockwise rotations around vertical axes. In several locations, lack of significant rotations in younger rocks constrains this kinematic pattern to have occurred during the Paleozoic. Previous tectonic models have explained these rotations as indicative of rigid-body rotations of large para-autochthonous crustal blocks or terranes. A different but simple tectonic model that accounts for this pattern is presented in which rotations are associated to crustal shortening and tectonic escape due to the collision of the allochthonous terrane of Precordillera in the Late Ordovician. This collision should have generated dextral shear zones in the back arc region of the convergent SW Gondwana margin, where systematic domino-like clockwise rotations of small crustal blocks accommodate crustal shortening. The Western Puna block, bordering the Precordillera terrane to the north, might have rotated counterclockwise as an independent microplate due to tectonic escape processes, in a fashion similar to the present-day relationship between the Anatolia block and the Arabian microplate. © 2010 Springer-Verlag. Fil:Spagnuolo, C.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Rapalini, A.E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2011 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14373254_v100_n2_p603_Spagnuolo http://hdl.handle.net/20.500.12110/paper_14373254_v100_n2_p603_Spagnuolo |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Block rotations Gondwana NW Argentina Paleomagnetism Paleozoic block rotation collision zone crustal shortening kinematics microplate Ordovician paleomagnetism Paleozoic shear zone Anatolia Argentina Chile La Rioja [Argentina] Sierra de Famatina Sierras Pampeanas Turkey |
| spellingShingle |
Block rotations Gondwana NW Argentina Paleomagnetism Paleozoic block rotation collision zone crustal shortening kinematics microplate Ordovician paleomagnetism Paleozoic shear zone Anatolia Argentina Chile La Rioja [Argentina] Sierra de Famatina Sierras Pampeanas Turkey Spagnuolo, Cecilia Mariel Rapalini, Augusto Ernesto Reinterpretation of the Ordovician rotations in NW Argentina and Northern Chile: A consequence of the Precordillera collision? |
| topic_facet |
Block rotations Gondwana NW Argentina Paleomagnetism Paleozoic block rotation collision zone crustal shortening kinematics microplate Ordovician paleomagnetism Paleozoic shear zone Anatolia Argentina Chile La Rioja [Argentina] Sierra de Famatina Sierras Pampeanas Turkey |
| description |
Early Paleozoic paleomagnetic data from NW Argentina and Northern Chile have shown large systematic rotations within two domains: one composed of the Western Puna that yields very large (up to 80°) counter-clockwise rotations, and the other formed by the Famatina Ranges and the Eastern Puna that shows (~40°) clockwise rotations around vertical axes. In several locations, lack of significant rotations in younger rocks constrains this kinematic pattern to have occurred during the Paleozoic. Previous tectonic models have explained these rotations as indicative of rigid-body rotations of large para-autochthonous crustal blocks or terranes. A different but simple tectonic model that accounts for this pattern is presented in which rotations are associated to crustal shortening and tectonic escape due to the collision of the allochthonous terrane of Precordillera in the Late Ordovician. This collision should have generated dextral shear zones in the back arc region of the convergent SW Gondwana margin, where systematic domino-like clockwise rotations of small crustal blocks accommodate crustal shortening. The Western Puna block, bordering the Precordillera terrane to the north, might have rotated counterclockwise as an independent microplate due to tectonic escape processes, in a fashion similar to the present-day relationship between the Anatolia block and the Arabian microplate. © 2010 Springer-Verlag. |
| author |
Spagnuolo, Cecilia Mariel Rapalini, Augusto Ernesto |
| author_facet |
Spagnuolo, Cecilia Mariel Rapalini, Augusto Ernesto |
| author_sort |
Spagnuolo, Cecilia Mariel |
| title |
Reinterpretation of the Ordovician rotations in NW Argentina and Northern Chile: A consequence of the Precordillera collision? |
| title_short |
Reinterpretation of the Ordovician rotations in NW Argentina and Northern Chile: A consequence of the Precordillera collision? |
| title_full |
Reinterpretation of the Ordovician rotations in NW Argentina and Northern Chile: A consequence of the Precordillera collision? |
| title_fullStr |
Reinterpretation of the Ordovician rotations in NW Argentina and Northern Chile: A consequence of the Precordillera collision? |
| title_full_unstemmed |
Reinterpretation of the Ordovician rotations in NW Argentina and Northern Chile: A consequence of the Precordillera collision? |
| title_sort |
reinterpretation of the ordovician rotations in nw argentina and northern chile: a consequence of the precordillera collision? |
| publishDate |
2011 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14373254_v100_n2_p603_Spagnuolo http://hdl.handle.net/20.500.12110/paper_14373254_v100_n2_p603_Spagnuolo |
| work_keys_str_mv |
AT spagnuoloceciliamariel reinterpretationoftheordovicianrotationsinnwargentinaandnorthernchileaconsequenceoftheprecordilleracollision AT rapaliniaugustoernesto reinterpretationoftheordovicianrotationsinnwargentinaandnorthernchileaconsequenceoftheprecordilleracollision |
| _version_ |
1768541813329625088 |