TY - JOUR
T1 - Correlated Geophysical, Geochemical, and Volcanological Manifestations of Plume‐ridge Interaction Along the Galápagos Spreading Center
AU - Detrick, R. S.
AU - Sinton, J. M.
AU - Ito, G.
AU - Canales, J. P.
AU - Behn, M.
AU - Balcic, T.
AU - Cushman, B.
AU - Dixon, Jacqueline E.
AU - Graham, D. W.
AU - Mahoney, J. J.
PY - 2002/1/1
Y1 - 2002/1/1
N2 - As the Galápagos hot spot is approached from the west along the Galápagos Spreading Center there are systematic increases in crustal thickness and in the K/Ti, Nb/Zr, 3 He/ 4 He, H 2 O, and Na 2 O content of lavas recovered from the spreading axis. These increases correlate with progressive transitions from rift valley to axial high morphology along with decreases in average swell depth, residual mantle Bouguer gravity anomaly, magma chamber depth, average lava Mg #, Ca/Al ratio, and the frequency of point‐fed versus fissure‐fed volcanism. Magma chamber depth and axial morphology display a “threshold” effect in which small changes in magma supply result in large changes in these variables. These correlated variations in geophysical, geochemical, and volcanological manifestations of plume‐ridge interaction along the western Galápagos Spreading Center reflect the combined effects of changes in mantle temperature and source composition on melt generation processes, and the consequences of these variations on magma supply, axial thermal structure, basalt chemistry, and styles of volcanism.
AB - As the Galápagos hot spot is approached from the west along the Galápagos Spreading Center there are systematic increases in crustal thickness and in the K/Ti, Nb/Zr, 3 He/ 4 He, H 2 O, and Na 2 O content of lavas recovered from the spreading axis. These increases correlate with progressive transitions from rift valley to axial high morphology along with decreases in average swell depth, residual mantle Bouguer gravity anomaly, magma chamber depth, average lava Mg #, Ca/Al ratio, and the frequency of point‐fed versus fissure‐fed volcanism. Magma chamber depth and axial morphology display a “threshold” effect in which small changes in magma supply result in large changes in these variables. These correlated variations in geophysical, geochemical, and volcanological manifestations of plume‐ridge interaction along the western Galápagos Spreading Center reflect the combined effects of changes in mantle temperature and source composition on melt generation processes, and the consequences of these variations on magma supply, axial thermal structure, basalt chemistry, and styles of volcanism.
KW - Mantle plumes
KW - mid‐ocean ridges
KW - hotspots
UR - https://digitalcommons.usf.edu/msc_facpub/1311
U2 - 10.1029/2002GC000350
DO - 10.1029/2002GC000350
M3 - Article
VL - 3
JO - Geochemistry, Geophysics, Geosystems
JF - Geochemistry, Geophysics, Geosystems
ER -