Along-rift propagation of Pleistocene-Holocene faults from a central volcano
The mechanisms of rift propagation are still not fully understood, especially at mid-oceanic ridges, owing to the inherent difficulty in collecting submarine data. Here, we investigate the fault slip profiles of the 60-km-long Theistareykir rift (northern Iceland) that may suggest the direction of a...
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ftunivmilanobic:oai:boa.unimib.it:10281/290299 2024-04-21T08:05:54+00:00 Along-rift propagation of Pleistocene-Holocene faults from a central volcano Tibaldi A. Corti N. Bonali F. L. Pasquare Mariotto F. Russo E. Tibaldi, A Corti, N Bonali, F Pasquare Mariotto, F Russo, E 2020 http://hdl.handle.net/10281/290299 https://doi.org/10.1016/j.jsg.2020.104201 eng eng Elsevier Ltd info:eu-repo/semantics/altIdentifier/wos/WOS:000595250500017 volume:141 journal:JOURNAL OF STRUCTURAL GEOLOGY http://hdl.handle.net/10281/290299 doi:10.1016/j.jsg.2020.104201 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85092207730 Dyke Fault propagation Magma chamber Mid-ocean ridge Rift Tectonic stresse Tectonic stresses GEO/03 - GEOLOGIA STRUTTURALE info:eu-repo/semantics/article 2020 ftunivmilanobic https://doi.org/10.1016/j.jsg.2020.104201 2024-03-28T01:17:19Z The mechanisms of rift propagation are still not fully understood, especially at mid-oceanic ridges, owing to the inherent difficulty in collecting submarine data. Here, we investigate the fault slip profiles of the 60-km-long Theistareykir rift (northern Iceland) that may suggest the direction of along-axis rift propagation. This is one of the few places on Earth where rifting processes and mid-oceanic ridge formation can be studied directly. Moreover, this rift hosts an active central volcano, and this enables to fully understand the relations between rift propagation and magma systems. We reconstructed the slip profiles of all the 281 main Pleistocene-Holocene faults that compose this N-S rift, by merging measurements performed in the field, collected by Unmanned Aerial Vehicle surveys, and derived from Digital Surface Models. Results indicate that north of the volcano, 75% of the asymmetric faults propagated northward; the value increases to 82% if the cumulated fault length is considered. South of the volcano, 47% of the asymmetric faults propagated southward, 54% if the cumulated fault length is considered. These data point to a dominant mechanism of along-axis propagation of the rift outward from the volcano, suggesting a genetic link with the underlying magma chamber. Two possible processes are suggested, which can also occur in combination: i) faults develop following lateral dyke propagation outward from the magma chamber, and ii) faults nucleate near the volcano as a consequence of the different crustal rock rheology produced by a higher heat flux. The rift architecture is complicated by the presence of tectonic zones with different dominant fault dips, separated by transversal accommodation zones. The latter also play the role of barriers guiding local fault propagation. Article in Journal/Newspaper Iceland Università degli Studi di Milano-Bicocca: BOA (Bicocca Open Archive) Journal of Structural Geology 141 104201 |
institution |
Open Polar |
collection |
Università degli Studi di Milano-Bicocca: BOA (Bicocca Open Archive) |
op_collection_id |
ftunivmilanobic |
language |
English |
topic |
Dyke Fault propagation Magma chamber Mid-ocean ridge Rift Tectonic stresse Tectonic stresses GEO/03 - GEOLOGIA STRUTTURALE |
spellingShingle |
Dyke Fault propagation Magma chamber Mid-ocean ridge Rift Tectonic stresse Tectonic stresses GEO/03 - GEOLOGIA STRUTTURALE Tibaldi A. Corti N. Bonali F. L. Pasquare Mariotto F. Russo E. Along-rift propagation of Pleistocene-Holocene faults from a central volcano |
topic_facet |
Dyke Fault propagation Magma chamber Mid-ocean ridge Rift Tectonic stresse Tectonic stresses GEO/03 - GEOLOGIA STRUTTURALE |
description |
The mechanisms of rift propagation are still not fully understood, especially at mid-oceanic ridges, owing to the inherent difficulty in collecting submarine data. Here, we investigate the fault slip profiles of the 60-km-long Theistareykir rift (northern Iceland) that may suggest the direction of along-axis rift propagation. This is one of the few places on Earth where rifting processes and mid-oceanic ridge formation can be studied directly. Moreover, this rift hosts an active central volcano, and this enables to fully understand the relations between rift propagation and magma systems. We reconstructed the slip profiles of all the 281 main Pleistocene-Holocene faults that compose this N-S rift, by merging measurements performed in the field, collected by Unmanned Aerial Vehicle surveys, and derived from Digital Surface Models. Results indicate that north of the volcano, 75% of the asymmetric faults propagated northward; the value increases to 82% if the cumulated fault length is considered. South of the volcano, 47% of the asymmetric faults propagated southward, 54% if the cumulated fault length is considered. These data point to a dominant mechanism of along-axis propagation of the rift outward from the volcano, suggesting a genetic link with the underlying magma chamber. Two possible processes are suggested, which can also occur in combination: i) faults develop following lateral dyke propagation outward from the magma chamber, and ii) faults nucleate near the volcano as a consequence of the different crustal rock rheology produced by a higher heat flux. The rift architecture is complicated by the presence of tectonic zones with different dominant fault dips, separated by transversal accommodation zones. The latter also play the role of barriers guiding local fault propagation. |
author2 |
Tibaldi, A Corti, N Bonali, F Pasquare Mariotto, F Russo, E |
format |
Article in Journal/Newspaper |
author |
Tibaldi A. Corti N. Bonali F. L. Pasquare Mariotto F. Russo E. |
author_facet |
Tibaldi A. Corti N. Bonali F. L. Pasquare Mariotto F. Russo E. |
author_sort |
Tibaldi A. |
title |
Along-rift propagation of Pleistocene-Holocene faults from a central volcano |
title_short |
Along-rift propagation of Pleistocene-Holocene faults from a central volcano |
title_full |
Along-rift propagation of Pleistocene-Holocene faults from a central volcano |
title_fullStr |
Along-rift propagation of Pleistocene-Holocene faults from a central volcano |
title_full_unstemmed |
Along-rift propagation of Pleistocene-Holocene faults from a central volcano |
title_sort |
along-rift propagation of pleistocene-holocene faults from a central volcano |
publisher |
Elsevier Ltd |
publishDate |
2020 |
url |
http://hdl.handle.net/10281/290299 https://doi.org/10.1016/j.jsg.2020.104201 |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000595250500017 volume:141 journal:JOURNAL OF STRUCTURAL GEOLOGY http://hdl.handle.net/10281/290299 doi:10.1016/j.jsg.2020.104201 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85092207730 |
op_doi |
https://doi.org/10.1016/j.jsg.2020.104201 |
container_title |
Journal of Structural Geology |
container_volume |
141 |
container_start_page |
104201 |
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