Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile
A paleomagnetic and AMS study on Eocene plutonic complexes in the Calama area, northern Chile, reveals high-temperature, high-coercivity magnetizations of dominantly thermoremanent origin and magnetic fabrics controlled by magnetite. The paleomagnetic results indicate that ~. 43. Ma plutons underwen...
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2015
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00401951_v654_n_p113_Somoza http://hdl.handle.net/20.500.12110/paper_00401951_v654_n_p113_Somoza |
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paper:paper_00401951_v654_n_p113_Somoza2023-06-08T15:04:01Z Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile Central Andes Chuquicamata Magnetic fabric Tectonic rotations Coercive force Deformation Geomagnetism Magnetic polarity Magnetism Metals Rotation Central Andes Chuquicamata Internal structure Low temperatures Magnetic fabrics Regional tectonics Solid state deformation Tectonic rotations Tectonics deformation emplacement Eocene foliation high temperature magnetic fabric paleomagnetism pluton tectonic rotation thermoremanent magnetization Andes Antofagasta Calama Chile A paleomagnetic and AMS study on Eocene plutonic complexes in the Calama area, northern Chile, reveals high-temperature, high-coercivity magnetizations of dominantly thermoremanent origin and magnetic fabrics controlled by magnetite. The paleomagnetic results indicate that ~. 43. Ma plutons underwent clockwise tectonic rotation, whereas adjacent ~. 39. Ma plutons did not undergo discernible rotation. This points to a middle Eocene age for the younger tectonic rotations associated with the Central Andean Rotation Pattern in the Chuquicamata-Calama area.The petrofabric in these rocks formed under conditions ranging from purely magmatic (i.e. before full crystallization) to low-temperature solid-state deformation. AMS and paleomagnetism suggest that the plutonic bodies were formed by progressive amalgamation of subvertical magma sheets spanning multiple magnetic polarity chrons. The parallelism between magmatic and tectonic foliations suggests that regional tectonic stress controlled ascent, emplacement and rock deformation during cooling. In this context, we suggest that magma ascent and emplacement in the upper crust likely exploited Mesozoic structures which were locally reactivated in the Eocene. © 2015 Elsevier B.V. 2015 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00401951_v654_n_p113_Somoza http://hdl.handle.net/20.500.12110/paper_00401951_v654_n_p113_Somoza |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Central Andes Chuquicamata Magnetic fabric Tectonic rotations Coercive force Deformation Geomagnetism Magnetic polarity Magnetism Metals Rotation Central Andes Chuquicamata Internal structure Low temperatures Magnetic fabrics Regional tectonics Solid state deformation Tectonic rotations Tectonics deformation emplacement Eocene foliation high temperature magnetic fabric paleomagnetism pluton tectonic rotation thermoremanent magnetization Andes Antofagasta Calama Chile |
| spellingShingle |
Central Andes Chuquicamata Magnetic fabric Tectonic rotations Coercive force Deformation Geomagnetism Magnetic polarity Magnetism Metals Rotation Central Andes Chuquicamata Internal structure Low temperatures Magnetic fabrics Regional tectonics Solid state deformation Tectonic rotations Tectonics deformation emplacement Eocene foliation high temperature magnetic fabric paleomagnetism pluton tectonic rotation thermoremanent magnetization Andes Antofagasta Calama Chile Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile |
| topic_facet |
Central Andes Chuquicamata Magnetic fabric Tectonic rotations Coercive force Deformation Geomagnetism Magnetic polarity Magnetism Metals Rotation Central Andes Chuquicamata Internal structure Low temperatures Magnetic fabrics Regional tectonics Solid state deformation Tectonic rotations Tectonics deformation emplacement Eocene foliation high temperature magnetic fabric paleomagnetism pluton tectonic rotation thermoremanent magnetization Andes Antofagasta Calama Chile |
| description |
A paleomagnetic and AMS study on Eocene plutonic complexes in the Calama area, northern Chile, reveals high-temperature, high-coercivity magnetizations of dominantly thermoremanent origin and magnetic fabrics controlled by magnetite. The paleomagnetic results indicate that ~. 43. Ma plutons underwent clockwise tectonic rotation, whereas adjacent ~. 39. Ma plutons did not undergo discernible rotation. This points to a middle Eocene age for the younger tectonic rotations associated with the Central Andean Rotation Pattern in the Chuquicamata-Calama area.The petrofabric in these rocks formed under conditions ranging from purely magmatic (i.e. before full crystallization) to low-temperature solid-state deformation. AMS and paleomagnetism suggest that the plutonic bodies were formed by progressive amalgamation of subvertical magma sheets spanning multiple magnetic polarity chrons. The parallelism between magmatic and tectonic foliations suggests that regional tectonic stress controlled ascent, emplacement and rock deformation during cooling. In this context, we suggest that magma ascent and emplacement in the upper crust likely exploited Mesozoic structures which were locally reactivated in the Eocene. © 2015 Elsevier B.V. |
| title |
Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile |
| title_short |
Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile |
| title_full |
Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile |
| title_fullStr |
Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile |
| title_full_unstemmed |
Tectonic rotations and internal structure of Eocene plutons in Chuquicamata, northern Chile |
| title_sort |
tectonic rotations and internal structure of eocene plutons in chuquicamata, northern chile |
| publishDate |
2015 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00401951_v654_n_p113_Somoza http://hdl.handle.net/20.500.12110/paper_00401951_v654_n_p113_Somoza |
| _version_ |
1768545684529610752 |