| 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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deMartin, B.J., R.A. Sohn, J.P. Canales, and S. Humphris , Kinematics and geometry of active detachment faulting beneath the Trans-Atlantic Geotraverse (TAG) hydrothermal field on the Mid-Atlantic Ridge, Geology, 35, 711-714, 2007
Abstract Newly acquired seismic refraction and microearthquake data from the Trans-Atlantic Geotraverse (TAG) segment of the Mid-Atlantic Ridge at 26°N reveal for the first time the geometry and seismic character of an active oceanic detachment fault. Hypocenters from 19,232 microearthquakes observed during an eight month ocean bottom seismometer deployment form an ~15-km-long, dome-shaped fault surface that penetrates to depths >7 km below the seafloor on a steeply dipping (~70°) interface. A tomographic model of compressional-wave velocities demonstrates that lower crustal rocks are being exhumed in the detachment footwall, which appears to roll over to a shallow dip of 20°±5° and become aseismic at a depth of ~3 km. Outboard of the detachment the exhumed lithosphere is deformed by ridge-parallel, antithetical normal faulting. Our results suggest that hydrothermal fluids at the TAG field exploit the detachment fault to extract heat from a region near the crust-mantle interface over long periods of time.
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