The University of Southampton
University of Southampton Institutional Repository

Influence of enhanced melt supply on upper crustal structure at a mid-ocean ridge discontinuity: A three-dimensional seismic tomographic study of 9N East Pacific Rise

Record type: Article

We present a three-dimensional upper crustal model of the 9degrees03'N overlapping spreading center (OSC) on the East Pacific Rise that assists in understanding the relationship between melt sills and upper crustal structure at a ridge discontinuity with enhanced melt supply at crustal levels. Our P wave velocity model obtained from tomographic inversion of similar to 70,000 crustal first arrival travel times suggests that the geometry of extrusive emplacement are significantly different beneath the overlapping spreading limbs. Extrusive volcanic rocks above the western melt sill are inferred to be thin ( similar to 250 m). More extensive accumulation of extrusives is inferred to the west than to the east of the western melt sill. The extrusive layer inferred above the eastern melt sill thickens from similar to 350 ( at the neovolcanic axis) to 550 m ( to the west of the melt sill). Volcanic construction is likely to be significant in the formation of ridge crest morphology at the OSC, particularly at the tip of the eastern limb. On the basis of our interpretation of the velocity model, we propose that enhanced magma supply at crustal levels at the OSC may provide an effective mechanism for the migration of ridge discontinuities. This "dynamic magma supply model'' may explain the commonly observed nonsteady migration pattern of ridge discontinuities by attributing this to the temporal fluctuations in melt availability to the overlapping spreading limbs

Full text not available from this repository.

Citation

Tong, C.H., Barton, P.J., White, R.S., Sinha, M.C., Singh, S.C., Pye, J.W., Hobbs, R.W., Bazin, S., Harding, A.J., Kent, G.M. and Orcutt, J.A. (2003) Influence of enhanced melt supply on upper crustal structure at a mid-ocean ridge discontinuity: A three-dimensional seismic tomographic study of 9N East Pacific Rise Journal of Geophysical Research, 108, (B10), art. 2464. (doi:10.1029/2002JB002163).

More information

Published date: 2003
Keywords: overlapping spreading center, magma supply, ridge segmentation, ridge propagation, crustal evolution, oceanic crust.

Identifiers

Local EPrints ID: 1305
URI: http://eprints.soton.ac.uk/id/eprint/1305
ISSN: 0148-0227
PURE UUID: 2b13e4f2-4701-4af0-87d3-d0e308464277

Catalogue record

Date deposited: 16 Apr 2004
Last modified: 17 Jul 2017 17:17

Export record

Altmetrics

Contributors

Author: C.H. Tong
Author: P.J. Barton
Author: R.S. White
Author: M.C. Sinha
Author: S.C. Singh
Author: J.W. Pye
Author: R.W. Hobbs
Author: S. Bazin
Author: A.J. Harding
Author: G.M. Kent
Author: J.A. Orcutt

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×