Woods Hole Oceanographic Institution

Juan Pablo Canales

»50. EPR Multi-sill plumbing system
Nature Geoscience, 2014

»49. Galapagos Spreading Center: Tomography
AGU Monograph, 2014

»48. Axial Volcano
Geology, 2014

»47. Melt-Mush along the EPR
JGR, 2014

»46. EPR Moho in 3D
G-cubed, 2014

»45. Melt bodies off the EPR
EPSL, 2014

»44. EPR Magma segmentation
Nature Geoscience, 2013

»43. TAG 3D P-wave velocity
G-cubed, 2012

»42. Atlantis core complex
G-cubed, 2012

»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 swell
EPSL, 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

Blackman, D. K., J. P. Canales, and A. Harding, Geophysical signatures of oceanic core complexes, Geophys. J. Int., 178, 593-613, 2009


Oceanic core complexes (OCCs) provide access to intrusive and ultramafic sections of young lithosphere and their structure and evolution contain clues about how the balance between magmatism and faulting controls the style of rifting that may dominate in a portion of a spreading centre for Myr timescales. Initial models of the development of OCCs depended strongly on insights available from continental core complexes and from seafloor mapping. While these frameworks have been useful in guiding a broader scope of studies and determining the extent of OCC formation along slow spreading ridges, as we summarize herein, results from the past decade highlight the need to reassess the hypothesis that reduced magma supply is a driver of long-lived detachment faulting. The aim of this paper is to review the available geophysical constraints on OCC structure and to look at what aspects of current models are constrained or required by the data. We consider sonar data (morphology and backscatter), gravity, magnetics, borehole geophysics and seismic reflection. Additional emphasis is placed on seismic velocity results (refraction) since this is where deviations from normal crustal accretion should be most readily quantified. However, as with gr avity and magnetic studies at OCCs, ambiguities are inhere nt in seismic interpretation, including within some processing/analysis steps. We briefly discuss some of these issues for each data type. Progress in understanding the shallow structure of OCCs (within ∼1 km of the seafloor) is considerable. Firm constraints on deeper structure, particularly characterization of the transition from dominantly mafic rock (and/or altered ultramafic rock) to dominantly fresh mantle peridotite, are not currently in hand. There is limited information on the structure and composition of the conjugate lithosphere accreted to the opposite plate while an OCC forms, commonly on the inside corner of a ridge-offset intersection. These gaps preclude full testing of current models. However, with the data in hand there are systematic patterns in OCC structure, such as the 1–2 Myr duration of this rifting style within a given ridge segment, the height of the domal cores with respect to surrounding seafloor, the correspondence of gravity highs with OCCs, and the persistence of corrugations that mark relative (palaeo) slip along the exposed detachment capping the domal cores. This compilation of geophysical results at OCCs should be useful to investigators new to the topic but we also target advanced researchers in our presentation and synthesis of findings to date.


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