| 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., G. Ito, J.P. Canales, R.S. Detrick, and J.M. Sinton, Constructing the crust along the Galapagos Spreading Center 91.3?-95.5? W: Correlation of seismic layer 2A with axial magma lens and topographic characteristics, J. Geophys. Res., 109, B10310, doi:10.1029/2004JB003066, 2004
[PDF]
Abstract
Multi-channel seismic reflection data are used to infer crustal accretion processes along the intermediate-spreading, Galapagos Spreading Center. East of 92.5?W, we image a magma lens beneath the ridge axis that is relatively shallow (1.0-2.5 km below the seafloor) and narrow (~0.5-1.5 km, cross-axis width). We also image a thin seismic layer 2A (0.24-0.42 km) that thickens away from the ridge axis by as much as 150%. West of 92.7?W, the magma lens is deeper (2.5-4.5 km) and wider (0.7-2.4-km), and layer 2A is thicker (0.36-0.66 km) and thickens off axis by <40%. The positive correlation between layer 2A thickness and magma lens depth supports the interpretation of layer 2A as the extrusive volcanic layer with thickness controlled by the pressure on the magma lens and its ability to push magma to the surface. Our findings also suggest that narrower magma lenses focus diking close the ridge axis such that lava that flows away from the ridge axis will blanket older flows and thicken the extrusive crust off axis. Flow of lava away from the ridge axis is probably promoted by the slope of the axial bathymetric high, which is largest east of 92.5?W. Indeed, west of ~94?W, layer 2A no longer thickens off axis the ?transitional? axial morphology in this region lacks a prominent bathymetric high. We detect no magma lens west of 94.7?W where a small axial valley appears. The above changes can be linked to the westward decrease in the magma and heat flux associated with the fading influence of the Galapagos hotspot on the Galapagos Spreading Center. |
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