Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia
Recent studies highlight the importance of annual-scale dike-induced rifting episodes in developing normal faults and graben along the active axis of magmatic divergent plate boundaries (MDPB). However, the longer-term (102-105 years) role of diking on the cumulative surface deformation and evolutio...
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ftkingabdullahun:oai:repository.kaust.edu.sa:10754/582715 2024-01-07T09:44:10+01:00 Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia Trippanera, D. Acocella, V. Ruch, Joel Abebe, B. King Abdullah University of Science and Technology (KAUST) Physical Science and Engineering (PSE) Division Roma Tre University; Rome Italy University of Addis Ababa; Addis Ababa Ethiopia 2015-11-27 application/pdf http://hdl.handle.net/10754/582715 https://doi.org/10.1002/2015TC003991 en eng American Geophysical Union (AGU) http://doi.wiley.com/10.1002/2015TC003991 Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia 2015:n/a Tectonics doi:10.1002/2015TC003991 02787407 Tectonics http://hdl.handle.net/10754/582715 This is the peer reviewed version of the following article: Trippanera, D., V. Acocella, J. Ruch, and B. Abebe (2015), Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia, Tectonics, 34, doi:10.1002/2015TC003991., which has been published in final form at http://doi.wiley.com/10.1002/2015TC003991. This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving. Article 2015 ftkingabdullahun https://doi.org/10.1002/2015TC003991 2023-12-09T20:18:46Z Recent studies highlight the importance of annual-scale dike-induced rifting episodes in developing normal faults and graben along the active axis of magmatic divergent plate boundaries (MDPB). However, the longer-term (102-105 years) role of diking on the cumulative surface deformation and evolution of MDPB is not yet well understood. To better understand the longer-term normal faults and graben along the axis of MDPB, we analyze fissure swarms in Iceland and Ethiopia. We first focus on the simplest case of immature fissure swarms, with single dike-fed eruptive fissures; these consist of a <1 km wide graben bordered by normal faults with displacement up to a few meters, consistent with theoretical models and geodetic data. A similar structural pattern is found, with asymmetric and multiple graben, within wider mature fissure swarms, formed by several dike-fed eruptive fissures. We then consider the lateral termination of normal faults along these graben, to detect their upward or downward propagation. Most faults terminate as open fractures on flat surface, suggesting downward fault propagation; this is consistent with recent experiments showing dike-induced normal faults propagating downward from the surface. However, some normal faults also terminate as open fractures on monoclines, which resemble fault propagation folds; this suggests upward propagation of reactivated buried faults, promoted by diking. These results suggest that fault growth and graben development, as well as the longer-term evolution of the axis of MDPB, may be explained only through dike emplacement and that any amagmatic faulting is not necessary. Article in Journal/Newspaper Iceland King Abdullah University of Science and Technology: KAUST Repository Tectonics 34 11 2318 2348 |
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Open Polar |
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King Abdullah University of Science and Technology: KAUST Repository |
op_collection_id |
ftkingabdullahun |
language |
English |
description |
Recent studies highlight the importance of annual-scale dike-induced rifting episodes in developing normal faults and graben along the active axis of magmatic divergent plate boundaries (MDPB). However, the longer-term (102-105 years) role of diking on the cumulative surface deformation and evolution of MDPB is not yet well understood. To better understand the longer-term normal faults and graben along the axis of MDPB, we analyze fissure swarms in Iceland and Ethiopia. We first focus on the simplest case of immature fissure swarms, with single dike-fed eruptive fissures; these consist of a <1 km wide graben bordered by normal faults with displacement up to a few meters, consistent with theoretical models and geodetic data. A similar structural pattern is found, with asymmetric and multiple graben, within wider mature fissure swarms, formed by several dike-fed eruptive fissures. We then consider the lateral termination of normal faults along these graben, to detect their upward or downward propagation. Most faults terminate as open fractures on flat surface, suggesting downward fault propagation; this is consistent with recent experiments showing dike-induced normal faults propagating downward from the surface. However, some normal faults also terminate as open fractures on monoclines, which resemble fault propagation folds; this suggests upward propagation of reactivated buried faults, promoted by diking. These results suggest that fault growth and graben development, as well as the longer-term evolution of the axis of MDPB, may be explained only through dike emplacement and that any amagmatic faulting is not necessary. |
author2 |
King Abdullah University of Science and Technology (KAUST) Physical Science and Engineering (PSE) Division Roma Tre University; Rome Italy University of Addis Ababa; Addis Ababa Ethiopia |
format |
Article in Journal/Newspaper |
author |
Trippanera, D. Acocella, V. Ruch, Joel Abebe, B. |
spellingShingle |
Trippanera, D. Acocella, V. Ruch, Joel Abebe, B. Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia |
author_facet |
Trippanera, D. Acocella, V. Ruch, Joel Abebe, B. |
author_sort |
Trippanera, D. |
title |
Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia |
title_short |
Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia |
title_full |
Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia |
title_fullStr |
Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia |
title_full_unstemmed |
Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia |
title_sort |
fault and graben growth along active magmatic divergent plate boundaries in iceland and ethiopia |
publisher |
American Geophysical Union (AGU) |
publishDate |
2015 |
url |
http://hdl.handle.net/10754/582715 https://doi.org/10.1002/2015TC003991 |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
http://doi.wiley.com/10.1002/2015TC003991 Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia 2015:n/a Tectonics doi:10.1002/2015TC003991 02787407 Tectonics http://hdl.handle.net/10754/582715 |
op_rights |
This is the peer reviewed version of the following article: Trippanera, D., V. Acocella, J. Ruch, and B. Abebe (2015), Fault and graben growth along active magmatic divergent plate boundaries in Iceland and Ethiopia, Tectonics, 34, doi:10.1002/2015TC003991., which has been published in final form at http://doi.wiley.com/10.1002/2015TC003991. This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving. |
op_doi |
https://doi.org/10.1002/2015TC003991 |
container_title |
Tectonics |
container_volume |
34 |
container_issue |
11 |
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2318 |
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2348 |
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1787425495545020416 |