| Publications | | » | 41. R2K Advances in Seismic Imaging Oceanography, 2012
 | | » | 40. R2K Seismic Studies Oceanography, 2012
 | | » | 39. Melt bodies off the EPR Nature Geoscience, 2012
 | | » | 38. JdF Plate: Gravity structure G-cubed, 2011
 | | » | 37. JdF Plate: Layer 2B structure G-cubed, 2011
 | | » | 36. Kane waveform tomography GRL, 2010
 | | » | 35. Kane Oceanic Core Complex G-cubed, 2009
 | | » | 34. Geophysical signatures of oceanic core complexes GJI, 2009
 | | » | 33. Accretion of the lower crust Nature, 2009
 | | » | 32. Faulting of the Juan de Fuca plate EPSL, 2009
 | | » | 31. Axial topography os the Galapagos Spreading Center G-cubed, 2008
 | | » | 30. Juan de Fuca Ridge flanks G-cubed, 2008
 | | » | 29. Seismic structure of oceanic core complexes G-cubed, 2008
 | | » | 28. Juan de Fuca Ridge: structure and hotspots G-cubed, 2008
 | | » | 27. Structure of the TAG segment, Mid-Atlantic Ridge G-cubed, 2007
 | | » | 26. Detachment faulting at TAG, Mid-Atlantic Ridge Geology, 2007
 | | » | 25. Structure of the Endeavour segment, Juan de Fuca Ridge JGR, 2007
 | | » | 24. Magma beneath Lucky Strike Hydrothermal Field Nature, 2006
 | | » | 23. Magma chamber of the Cleft segment, Juan de Fuca Ridge EPSL, 2006
 | | » | 22. Topography and magmatism at the Juan de Fuca Ridge Geology, 2006
 | | » | 21. Structure of the southern Juan de Fuca Ridge JGR, 2005
 | | » | 20. Sub-crustal magma lenses Nature, 2005
 | | » | 19. Constructing the crust at the Galapagos Spreading Center JGR, 2004
 | | » | 18. Atlantis core complex EPSL, 2004
 | | » | 17. Morphology of the Galapagos Spreading Center G-cubed, 2003
 | | » | 16. Crustal structure of the East Pacific Rise GJI, 2003
 | | » | 15. Plume-ridge interaction along the Galapagos Spreading Center G-cubed, 2002
 | | » | 14. Compensation of the Galapagos swellEPSL, 2002
 | | » | 13. Structure of Tenerife, Canary Islands JVGR, 2000
 | | » | 12. Underplating in the Canary Islands JVGR, 2000
 | | » | 11. Structure of the Mid-Atlantic Ridge (MARK, 23?20'N) JGR, 2000
 | | » | 10. Structure of the Mid-Atlantic Ridge (35?N) JGR, 2000
 | | » | 9. Structure of Gran Canaria, Canary Islands J. Geodyn., 1999
 | | » | 8. Structure of overlapping spreading centers in the MELT area GRL, 1998
 | | » | 7. Crustal thickness in the MELT area Science, 1998
 | | » | 6. The MELT experiment Science, 1998
 | | » | 5. The Canary Islands swell GJI, 1998
 | | » | 4. Morphology of the Galapagos Spreading Center JGR, 1997
 | | » | 3. Faulting of slow-spreading oceanic crust Geology, 1997
 | | » | 2. Flexure beneath Tenerife, Canary Islands EPSL, 1997
 | | » | 1. Elastic thickness in the Canary Islands GRL, 1994
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Blacic, T.M., G. Ito, A.K. Shah, J.P. Canales, and J. Lin, Axial topography and partial melt in the crust and mantle beneath the Western Galapagos Spreading Center, Geochem., Geophys., Geosyst. 9, Q12005, doi:10.1029/2008GC002100, 2008
Abstract The hot spot-influenced western Galapagos 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.
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