Development of volcanic passive margins: Two‐dimensional laboratory models
International audience Volcanic margins are inferred to develop during lithosphere extension above mantle plumes. Continental breakup is characterized in such case by (1) thick seaward dipping lava sequences, (2) plutonic complexes associated with dyke swarms parallel to the coast, and (3) zones of...
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ftunivpau:oai:HAL:hal-04617926v1 2024-09-15T18:24:16+00:00 Development of volcanic passive margins: Two‐dimensional laboratory models Callot, Jean‐paul Grigné, Cécile Geoffroy, Laurent Brun, Jean‐pierre Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR) TOTAL FINA ELF-Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS) 2001-02 https://hal.science/hal-04617926 https://doi.org/10.1029/2000TC900030 en eng HAL CCSD American Geophysical Union (AGU) info:eu-repo/semantics/altIdentifier/doi/10.1029/2000TC900030 hal-04617926 https://hal.science/hal-04617926 doi:10.1029/2000TC900030 ISSN: 0278-7407 EISSN: 1944-9194 Tectonics https://hal.science/hal-04617926 Tectonics, 2001, 20 (1), pp.148-159. ⟨10.1029/2000TC900030⟩ [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2001 ftunivpau https://doi.org/10.1029/2000TC900030 2024-06-24T14:06:36Z International audience Volcanic margins are inferred to develop during lithosphere extension above mantle plumes. Continental breakup is characterized in such case by (1) thick seaward dipping lava sequences, (2) plutonic complexes associated with dyke swarms parallel to the coast, and (3) zones of high seismic velocity in the lower crust likely attributable to magma underplating. Comparison with classical nonvolcanic passive margins shows that a striking but nonsystematic structural character of volcanic margins is the narrowness of the domain of crustal attenuation (down to 50 km). The existence of a soft magma body at depth may considerably affect the mechanical behavior of the lithosphere during continental breakup. Here we present a series of scaled experiments designed to study the mechanical effects on lithospheric extension of rheological heterogeneities caused by magma emplacement at various levels. Four‐layer models were constructed with sand and silicone putties in order to represent the brittle and ductile layers of both crust and lithospheric mantle. The underplated magma bodies were simulated by low‐viscosity silicone putty with variable geometry and location. The experimental results are compared to interpreted refraction seismic profiles across volcanic margins in the North Atlantic. A narrow zone of necking is obtained only when the high‐strength layer of the sub‐Moho mantle is interrupted by a heterogeneity of low viscosity representing an underplated magma body. As in cross sections of volcanic margins, models show weak deformation in the brittle upper crust. Sequential addition of sand in the rifted area during extension results in the development of layers dipping toward the rift center. This geometrical pattern is directly comparable to the seaward dipping reflectors sequences. However, the normal faults which developed within the seaward dipping wedge have vergence opposite to the one currently observed in volcanic margins. This suggests a possible component of mantle‐generated stresses ... Article in Journal/Newspaper North Atlantic HAL e2s UPPA (Université de Pau et des Pays de l'Adour) Tectonics 20 1 148 159 |
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HAL e2s UPPA (Université de Pau et des Pays de l'Adour) |
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ftunivpau |
language |
English |
topic |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
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[SDU.STU]Sciences of the Universe [physics]/Earth Sciences Callot, Jean‐paul Grigné, Cécile Geoffroy, Laurent Brun, Jean‐pierre Development of volcanic passive margins: Two‐dimensional laboratory models |
topic_facet |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience Volcanic margins are inferred to develop during lithosphere extension above mantle plumes. Continental breakup is characterized in such case by (1) thick seaward dipping lava sequences, (2) plutonic complexes associated with dyke swarms parallel to the coast, and (3) zones of high seismic velocity in the lower crust likely attributable to magma underplating. Comparison with classical nonvolcanic passive margins shows that a striking but nonsystematic structural character of volcanic margins is the narrowness of the domain of crustal attenuation (down to 50 km). The existence of a soft magma body at depth may considerably affect the mechanical behavior of the lithosphere during continental breakup. Here we present a series of scaled experiments designed to study the mechanical effects on lithospheric extension of rheological heterogeneities caused by magma emplacement at various levels. Four‐layer models were constructed with sand and silicone putties in order to represent the brittle and ductile layers of both crust and lithospheric mantle. The underplated magma bodies were simulated by low‐viscosity silicone putty with variable geometry and location. The experimental results are compared to interpreted refraction seismic profiles across volcanic margins in the North Atlantic. A narrow zone of necking is obtained only when the high‐strength layer of the sub‐Moho mantle is interrupted by a heterogeneity of low viscosity representing an underplated magma body. As in cross sections of volcanic margins, models show weak deformation in the brittle upper crust. Sequential addition of sand in the rifted area during extension results in the development of layers dipping toward the rift center. This geometrical pattern is directly comparable to the seaward dipping reflectors sequences. However, the normal faults which developed within the seaward dipping wedge have vergence opposite to the one currently observed in volcanic margins. This suggests a possible component of mantle‐generated stresses ... |
author2 |
Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR) TOTAL FINA ELF-Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Callot, Jean‐paul Grigné, Cécile Geoffroy, Laurent Brun, Jean‐pierre |
author_facet |
Callot, Jean‐paul Grigné, Cécile Geoffroy, Laurent Brun, Jean‐pierre |
author_sort |
Callot, Jean‐paul |
title |
Development of volcanic passive margins: Two‐dimensional laboratory models |
title_short |
Development of volcanic passive margins: Two‐dimensional laboratory models |
title_full |
Development of volcanic passive margins: Two‐dimensional laboratory models |
title_fullStr |
Development of volcanic passive margins: Two‐dimensional laboratory models |
title_full_unstemmed |
Development of volcanic passive margins: Two‐dimensional laboratory models |
title_sort |
development of volcanic passive margins: two‐dimensional laboratory models |
publisher |
HAL CCSD |
publishDate |
2001 |
url |
https://hal.science/hal-04617926 https://doi.org/10.1029/2000TC900030 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
ISSN: 0278-7407 EISSN: 1944-9194 Tectonics https://hal.science/hal-04617926 Tectonics, 2001, 20 (1), pp.148-159. ⟨10.1029/2000TC900030⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2000TC900030 hal-04617926 https://hal.science/hal-04617926 doi:10.1029/2000TC900030 |
op_doi |
https://doi.org/10.1029/2000TC900030 |
container_title |
Tectonics |
container_volume |
20 |
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1 |
container_start_page |
148 |
op_container_end_page |
159 |
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1810464599335501824 |