Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge
Most models of melt generation beneath mid-ocean ridges predict significant reduction of melt production at ultraslow spreading rates (full spreading rates <20mm/yr) and consequently they predict thinned oceanic crust. The 1,800-km-long Arctic Gakkel mid-ocean ridge is an ideal location to test s...
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ftawi:oai:epic.awi.de:8601 2023-09-05T13:15:49+02:00 Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge Jokat, Wilfried Ritzmann, O. Schmidt-Aursch, Mechita C. Drachev, S. Gauger, S. Snow, J. 2003 https://epic.awi.de/id/eprint/8601/ https://hdl.handle.net/10013/epic.19127 unknown Jokat, W. orcid:0000-0002-7793-5854 , Ritzmann, O. , Schmidt-Aursch, M. C. orcid:0000-0002-2393-4514 , Drachev, S. , Gauger, S. and Snow, J. (2003) Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge , Nature, 423 , pp. 962-965 . hdl:10013/epic.19127 EPIC3Nature, 423, pp. 962-965 Article isiRev 2003 ftawi 2023-08-22T19:47:32Z Most models of melt generation beneath mid-ocean ridges predict significant reduction of melt production at ultraslow spreading rates (full spreading rates <20mm/yr) and consequently they predict thinned oceanic crust. The 1,800-km-long Arctic Gakkel mid-ocean ridge is an ideal location to test such models, as it is by far the slowest portion of the global mid-ocean-ridge spreading system, with a full spreading rate ranging from 6 to 13 mm/yr. Furthermore, in contrast to some other ridge systems, the spreading direction on the Gakkel ridge is not oblique and the rift valley is not offset by major transform faults. Here we present seismic evidence for the presence of exceptionally thin crust along the Gakkel ridge rift valley with crustal thicknesses varying between 1.9 and 3.3km (compared to the more usual value of 7 km found on medium- to fast-spreading mid-ocean ridges). Almost 8,300km of closely spaced aeromagnetic profiles across the rift valley show the presence of discrete volcanic centres along the ridge, which we interpret as evidence for strongly focused, three-dimensional magma supply. The traces of these eruptive centres can be followed to crustal ages of ca. 25Myr off-axis, implying that these magma production and transport systems have been stable over this timescale. Article in Journal/Newspaper Arctic Arctic Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Arctic Gakkel Ridge ENVELOPE(90.000,90.000,87.000,87.000) |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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ftawi |
language |
unknown |
description |
Most models of melt generation beneath mid-ocean ridges predict significant reduction of melt production at ultraslow spreading rates (full spreading rates <20mm/yr) and consequently they predict thinned oceanic crust. The 1,800-km-long Arctic Gakkel mid-ocean ridge is an ideal location to test such models, as it is by far the slowest portion of the global mid-ocean-ridge spreading system, with a full spreading rate ranging from 6 to 13 mm/yr. Furthermore, in contrast to some other ridge systems, the spreading direction on the Gakkel ridge is not oblique and the rift valley is not offset by major transform faults. Here we present seismic evidence for the presence of exceptionally thin crust along the Gakkel ridge rift valley with crustal thicknesses varying between 1.9 and 3.3km (compared to the more usual value of 7 km found on medium- to fast-spreading mid-ocean ridges). Almost 8,300km of closely spaced aeromagnetic profiles across the rift valley show the presence of discrete volcanic centres along the ridge, which we interpret as evidence for strongly focused, three-dimensional magma supply. The traces of these eruptive centres can be followed to crustal ages of ca. 25Myr off-axis, implying that these magma production and transport systems have been stable over this timescale. |
format |
Article in Journal/Newspaper |
author |
Jokat, Wilfried Ritzmann, O. Schmidt-Aursch, Mechita C. Drachev, S. Gauger, S. Snow, J. |
spellingShingle |
Jokat, Wilfried Ritzmann, O. Schmidt-Aursch, Mechita C. Drachev, S. Gauger, S. Snow, J. Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge |
author_facet |
Jokat, Wilfried Ritzmann, O. Schmidt-Aursch, Mechita C. Drachev, S. Gauger, S. Snow, J. |
author_sort |
Jokat, Wilfried |
title |
Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge |
title_short |
Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge |
title_full |
Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge |
title_fullStr |
Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge |
title_full_unstemmed |
Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge |
title_sort |
geophysical evidence for reduced melt production on the arctic ultra-slow gakkel mid-ocean ridge |
publishDate |
2003 |
url |
https://epic.awi.de/id/eprint/8601/ https://hdl.handle.net/10013/epic.19127 |
long_lat |
ENVELOPE(90.000,90.000,87.000,87.000) |
geographic |
Arctic Gakkel Ridge |
geographic_facet |
Arctic Gakkel Ridge |
genre |
Arctic Arctic |
genre_facet |
Arctic Arctic |
op_source |
EPIC3Nature, 423, pp. 962-965 |
op_relation |
Jokat, W. orcid:0000-0002-7793-5854 , Ritzmann, O. , Schmidt-Aursch, M. C. orcid:0000-0002-2393-4514 , Drachev, S. , Gauger, S. and Snow, J. (2003) Geophysical evidence for reduced melt production on the Arctic ultra-slow Gakkel mid-ocean ridge , Nature, 423 , pp. 962-965 . hdl:10013/epic.19127 |
_version_ |
1776197642197401600 |