Axial high topography and partial melt in the crust and mantle beneath the western Galapagos Spreading Center Blacic, Tanya M. Ito, Garrett T. Shah, Anjana K. Canales, J. Pablo Lin, Jian 2010-04-21T13:50:53Z 2010-04-21T13:50:53Z 2008-12-04
dc.description Author Posting. © American Geophysical Union, 2008. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 9 (2008): Q12005, doi:10.1029/2008GC002100. en_US
dc.description.abstract The hot spot-influenced western Galápagos Spreading Center (GSC) has an axial topographic high that reaches heights of ∼700 m relative to seafloor depth ∼25 km from the axis. We investigate the cause of the unusual size of the axial high using a model that determines the flexural response to loads resulting from the thermal and magmatic structure of the lithosphere. The thermal structure simulated is appropriate for large amounts of cooling by hydrothermal circulation, which tends to minimize the amount of partial melt needed to explain the axial topography. Nonetheless, results reveal that the large axial high near 92°W requires that either the crust below the magma lens contains >35% partial melt or that 20% melt is present in the lower crust and at least 3% in the mantle within a narrow column (<∼10 km wide) extending to depths of 45–65 km. Because melt fractions >35% in the crust are considered unreasonable, it is likely that much of the axial high region of the GSC is underlain by a narrow region of partially molten mantle of widths approaching those imaged seismically beneath the East Pacific Rise. A narrow zone of mantle upwelling and melting, driven largely by melt buoyancy, is a plausible explanation. en_US
dc.description.sponsorship Ito was supported by grants NSF-OCE- 0327051 and NSF-OCE-0351234. en_US
dc.format.mimetype application/pdf
dc.identifier.citation Geochemistry Geophysics Geosystems 9 (2008): Q12005 en_US
dc.identifier.doi 10.1029/2008GC002100
dc.language.iso en_US en_US
dc.publisher American Geophysical Union en_US
dc.subject Axial high en_US
dc.subject Galapagos Spreading Center en_US
dc.subject Partial melt en_US
dc.subject Lithospheric flexure en_US
dc.title Axial high topography and partial melt in the crust and mantle beneath the western Galapagos Spreading Center en_US
dc.type Article en_US
dspace.entity.type Publication
relation.isAuthorOfPublication c7b148f7-ec41-4bd1-806f-ea86ba761e34
relation.isAuthorOfPublication 08501267-1bab-46da-95ff-907f1f680825
relation.isAuthorOfPublication 79c62e54-eba3-47c7-8166-7acec5979c59
relation.isAuthorOfPublication f827099c-da45-43b6-86aa-2791b9a06566
relation.isAuthorOfPublication aec4d642-5f3a-431e-8d76-0058b48cdb56
relation.isAuthorOfPublication.latestForDiscovery c7b148f7-ec41-4bd1-806f-ea86ba761e34
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
1.65 MB
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
1.97 KB
Item-specific license agreed upon to submission