@article{fdi:010042972,
  title = {{S}eismic structure of the {C}arnegie ridge and the nature of the {G}alapagos hotspot},
  author = {{S}allares, {V}. and {C}harvis, {P}hilippe and {F}lueh, {E}. {R}. and {B}ialas, {J}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {G}alapagos volcanic province ({GVP}) includes several aseismic ridges resulting from the interaction between the {G}alapagos hotspot ({GHS}) and the {C}ocos-{N}azca spreading centre ({CNSC}). {T}he most prominent are the {C}ocos, {C}arnegie and {M}alpelo ridges. {I}n this work, we investigate the seismic structure of the {C}arnegie ridge along two profiles acquired during the {S}outh {A}merican {L}ithospheric {T}ransects {A}cross {V}olcanic {R}idges ({SALIERI}) 2001 experiment. {M}aximum crustal thickness is similar to 19 km in the central {C}arnegie profile, located at similar to 85 degrees {W} over a 19-20 {M}yr old oceanic crust, and only similar to 13 km in the eastern {C}arnegie profile, located at similar to 82 degrees {W} over a 11-12 {M}yr old oceanic crust. {T}he crustal velocity models are subsequently compared with those obtained in a previous work along three other profiles over the {C}ocos and {M}alpelo ridges, two of which are located at the conjugate positions of the {C}arnegie ones. {O}ceanic layer 2 thickness is quite uniform along the five profiles regardless of the total crustal thickness variations, hence crustal thickening is mainly accommodated by layer 3. {L}ower crustal velocities are systematically lower where the crust is thicker, thus contrary to what would be expected from melting of a hotter than normal mantle. {T}he velocity-derived crustal density models account for the gravity and depth anomalies considering uniform and normal mantle {E} densities (3300 kg m(-3)), which confirms that velocity models are consistent with gravity and topography data, and indicates that the ridges are isostatically compensated at the base of the crust. {F}inally, a two-dimensional (2-{D}) steady-state mantle melting model is developed and used to illustrate that the crust of the ridges does not seem to be the product of anomalous mantle temperatures, even if hydrous melting coupled with vigorous subsolidus upwelling is considered in the model. {I}n contrast, we show that upwelling of a normal temperature but fertile mantle source that may result from recycling of oceanic crust prior to melting, accounts more easily for the estimated seismic structure as well as for isotopic, trace element and major element patterns of the {GVP} basalts.},
  keywords = {aseismic ridge ; {G}alapagos hotspot ; gravity ; mantle melting ; seismic tomography ; {PACIFIQUE} ; {GALAPAGOS} {ILES}},
  booktitle = {},
  journal = {{G}eophysical {J}ournal {I}nternational},
  volume = {161},
  numero = {3},
  pages = {763--788},
  ISSN = {0956-540{X}},
  year = {2005},
  DOI = {10.1111/j.1365-246{X}.2005.02592.x},
  URL = {https://www.documentation.ird.fr/hor/fdi:010042972},
}