Ferrobasalts from the Spiess Ridge segment of the Southwest Indian Ridge

Details Ferrobasalts from the Spiess Ridge segment of the Southwest Indian Ridge Ferrobasalts from the Spiess Ridge segment of the Southwest Indian Ridge

Oct 1982

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982e%26psl..60..437l&link_type=abstract

Earth and Planetary Science Letters, Volume 60, Issue 3, p. 437-451.

Computer Science

19

Scientific paper

Highly vesicular, microporphyritic basaltic rocks have been dredged from the slow-spreading Spiess Ridge segment of the Southwest Indian Ridge. All the samples recovered are hyalocrystalline with plagioclase, clinopyroxene and olivine as phenocryst and microphenocryst phases. Titanomagnetite occurs as euhedral microphenocrysts in some of the more evolved samples. In terms of bulk rock and quench glass chemistry the lavas are characterised by highly evolved compositions (e.g. FeO*=10.3-14.2% TiO2=2.0-3.4% K2O=0.50-1.1% MgO=6.0-3.5% Zr=160-274 ppm; Nb=14-32 ppm) and can be classified as ferrobasalts. Isotopic and incompatible element ratios of the lavas (e.g.87Sr/86Sr=0.70325-0.70333 Zr/Nb=8.4-11.3 Y/Nb=2.3-1.4) indicate their strongly ``enriched'' nature (see also Dickey et al. [6]).
Quantitative major and trace element modelling indicates that most of the compositional variations observed can be attributed to low-pressure fractional crystallisation of plagioclase, clinopyroxene and minor olivine and titanomagnetite. The range in composition can be accounted for by up to 65% fractional crystallisation.
We suggest that the extreme differentiation of the Spiess Ridge lavas is related not to spreading rate, but to rate of magma supply. The basaltic melts appear to have evolved in a newly established zone of magmatic activity, associated with the most recent northward jump of the Bouvet triple junction, where they were effectively isolated from significant admixture of primitive magmas.

Affiliated with

Also associated with

No associations

Rating

Ferrobasalts from the Spiess Ridge segment of the Southwest Indian Ridge does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ferrobasalts from the Spiess Ridge segment of the Southwest Indian Ridge, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ferrobasalts from the Spiess Ridge segment of the Southwest Indian Ridge will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1029840