Seafloor photo-geology and sonar terrain modeling at the 9°N overlapping spreading center, East Pacific Rise
Klein, Emily M.
White, Scott M.
Nunnery, James Andrew
Mason-Stack, Jessica L.
Wanless, V. Dorsey
Perfit, Michael R.
Waters, Christopher L.
Sims, Kenneth W. W.
Fornari, Daniel J.
Zaino, Anne J.
Ridley, W. Ian
MetadataShow full item record
KeywordMid-ocean ridge; Overlapping spreading center; Melt lens; Axial magma chamber; Dike; Ocean crust
A fundamental goal in the study of mid-ocean ridges is to understand the relationship between the distribution of melt at depth and seafloor features. Building on geophysical information on subsurface melt at the 9°N overlapping spreading center on the East Pacific Rise, we use terrain modeling (DSL-120A side scan and bathymetry), photo-geology (Jason II and WHOI TowCam), and geochemical data to explore this relationship. Terrain modeling identified four distinct geomorphic provinces with common seafloor characteristics that correspond well to changes in subsurface melt distribution. Visual observations were used to interpret terrain modeling results and to establish a relative seafloor age scale, calibrated with radiometric age dates, to identify areas of recent volcanism. On the east limb, recent eruptions in the north are localized over the margins of the 4 km wide asymmetric melt sill, forming a prominent off-axis pillow ridge. Along the southern east limb, recent eruptions occur along a neovolcanic ridge that hugs the overlap basin and lies several kilometers west of the plunging melt sill. Our results suggest that long-term southward migration of the east limb occurs through a series of diking events with a net southward propagation direction. Examining sites of recent eruptions in the context of geophysical data on melt distribution in the crust and upper mantle suggests melt may follow complex paths from depth to the surface. Overall, our findings emphasize the value of integrating information obtained from photo-geology, terrain modeling, lava geochemistry and petrography, and geophysics to constrain the nature of melt delivery at mid-ocean ridges.
© The Author(s), 2013. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Geochemistry, Geophysics, Geosystems 14 (2013): 5146–5170, doi:10.1002/2013GC004858.
Suggested CitationArticle: Klein, Emily M., White, Scott M., Nunnery, James Andrew, Mason-Stack, Jessica L., Wanless, V. Dorsey, Perfit, Michael R., Waters, Christopher L., Sims, Kenneth W. W., Fornari, Daniel J., Zaino, Anne J., Ridley, W. Ian, "Seafloor photo-geology and sonar terrain modeling at the 9°N overlapping spreading center, East Pacific Rise", Geochemistry, Geophysics, Geosystems 14 (2013): 5146–5170, DOI:10.1002/2013GC004858, https://hdl.handle.net/1912/6490
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivs 3.0
Showing items related by title, author, creator and subject.
Escartin Guiral, Javier E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1996-08)Two-thirds of the Earth's surface is oceanic crust formed by magmatic and tectonic processes along mid-ocean ridges. Slow-spreading ridges, such as the Mid-Atlantic Ridge, are discontinuous and composed of ridge segments. ...
Jaroslow, Gary E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1996-12)The objective of this Thesis was to interpret the structural development of slowspreading ridge segments by: 1) delineating the nature, magnitude, and relative importance of primary tectonic and volcanic processes that ...
Hosford, Allegra (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2001-09)Half of the ocean crust is formed at spreading centers with total opening rates less than 40 km/Myr. The objective of this Thesis is to investigate temporal variations in active ridge processes and crustal aging at ...