| 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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Sinton, J.M., R.S. Detrick, J.P. Canales, G. Ito, and M. Behn, Morphology and segmentation of the western Galapagos Spreading Center, 90.5??98?W: Plume-ridge interaction at an intermediate spreading ridge, Geochem., Geophys., Geosys., 4 (12), 8515, doi:10.1029/2003GC000609, 2003
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Abstract Complete multibeam bathymetric coverage of the western Galapagos Spreading Center (GSC) between 90.5?W and 98?W reveals the fine-scale morphology, segmentation and influence of the Galapagos hotspot on this intermediate spreading ridge. The western GSC comprises three morphologically defined provinces: A Western Province, located farthest from the Galapagos hotspot west of 95?30?W, is characterized by an axial deep, rift valley morphology with individual, overlapping, E-W striking segments separated by non-transform offsets; A Middle Province, between the propagating rift tips at 93?15?W and 95?30?W, with transitional axial morphology strikes ~276?; An Eastern Province, closest to the Galapagos hotspot between the ~90?50?W Galapagos Transform and 93?15?W, with an axial high morphology generally less than 1800 m deep, strikes ~280?. At a finer scale, the axial region consists of 32 individual segments defined on the basis of smaller, mainly < 2 km, offsets. These offsets mainly step left in the Western and Middle Provinces, and right in the Eastern Province. Glass compositions indicate that the GSC is segmented magmatically into 8 broad regions, with Mg # generally decreasing to the west within each region. Striking differences in bathymetric and lava fractionation patterns between the propagating rifts with tips at 93?15?W and 95?30?W reflects lower overall magma supply and larger offset distance at the latter. The structure of the Eastern Province is complicated by the intersection of a series of volcanic lineaments that appear to radiate away from a point located on the northern edge of the Galapagos platform, close to the southern limit of the Galapagos Fracture Zone. Where these lineaments intersect the GSC, the ridge axis is displaced to the south through a series of overlapping spreading centers (OSCs); abandoned OSC limbs lie even farther south. We propose that southward displacement of the axis is promoted during intermittent times of increased plume activity, when lithospheric zones of weakness become volcanically active. Following cessation of the increased plume activity, the axis straightens by decapitating southernmost OSC limbs during short-lived propagation events. This process contributes to the number of right stepping offsets in the Eastern Province. |
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