Journal articles
Correlated patterns in hydrothermal plume distribution and apparent magmatic budget along 2500 km of the Southeast Indian Ridge
Abstract : Multiple geological processes affect the distribution of hydrothermal venting along a mid-ocean ridge. Deciphering the role of a specific process is often frustrated by simultaneous changes in other influences. Here we take advantage of the almost constant spreading rate (65–71 mm/yr) along 2500 km of the Southeast Indian Ridge (SEIR) between 77 E and 99 E to examine the spatial density of hydrothermal venting relative to regional and segment-scale changes in the apparent magmatic budget. We use 227 vertical profiles of light backscatter and (on 41 profiles) oxidation-reduction potential along 27 first and second-order ridge segments on and adjacent to the Amsterdam-St. Paul (ASP) Plateau to map p h , the fraction of casts detecting a plume. At the regional scale, venting on the five segments cross-ing the magma-thickened hot spot plateau is almost entirely suppressed (p h 5 0.02). Conversely, the com-bined p h (0.34) from all other segments follows the global trend of p h versus spreading rate. Off the ASP Plateau, multisegment trends in p h track trends in the regional axial depth, high where regional depth increases and low where it decreases. At the individual segment scale, a robust correlation between p h and cross-axis inflation for first-order segments shows that different magmatic budgets among first-order segments are expressed as different levels of hydrothermal spatial density. This correlation is absent among second-order segments. Eighty-five percent of the plumes occur in eight clusters totaling 350 km. We hypothesize that these clusters are a minimum estimate of the length of axial melt lenses underlying this section of the SEIR.
Cited literature [47 references]
https://hal-insu.archives-ouvertes.fr/insu-01078730
Contributor : Adminhal Univbrestbu <>
Submitted on : Thursday, October 30, 2014 - 10:06:02 AM
Last modification on : Thursday, October 15, 2020 - 4:07:12 AM
Long-term archiving on: : Monday, February 2, 2015 - 3:51:46 PM
Contributor : Adminhal Univbrestbu <>
Submitted on : Thursday, October 30, 2014 - 10:06:02 AM
Last modification on : Thursday, October 15, 2020 - 4:07:12 AM
Long-term archiving on: : Monday, February 2, 2015 - 3:51:46 PM
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