MORPHOLOGY OF A SUPERFAST MIDOCEAN RIDGE CREST AND FLANKS - THE EAST PACIFIC RISE, 7-DEGREES-9-DEGREES-S

Detailed bathymetric data from a Hydrosweep multibeam sonar survey of a 250 km-long portion of the 'superfast'-spreading southern East Pacific Rise crest and flanks show that the along-axis variation in morphology and axial depth differs significantly from that observed at the fast-spreading northern East Pacific Rise. While the deep mantle upwelling pattern is similar under the nor-them and southern East Pacific Rise, our observations require that the connectivity of the shallow, subcrestal plumbing system be more efficient beneath the 'super-fast' spreading southern East Pacific Rise than beneath the slower spreading northern East Pacific Rise.