Library Open Repository

Petrogenetic variability along the North–South Propagating Spreading Center of the North Fiji Basin

Downloads

Downloads per month over past year

Fleutelot, C and Eissen, JP and Dosso, L and Juteau, T and Launeau, P and Bollinger, C and Cotten, J and Danyushevsky, LV and Savoyant, L (2005) Petrogenetic variability along the North–South Propagating Spreading Center of the North Fiji Basin. Mineralogy and Petrology, 83 (1). pp. 55-86. ISSN 0930-0708

[img] PDF
Fleutelot_et_al_2005_MINER_PETROL.pdf | Request a copy
Full text restricted
Available under University of Tasmania Standard License.

Abstract

Previous studies on propagating rifts suggested that segmentation of a spreading axis could represent the superficial mark of mantle behavior (Sinton et al., 1983; Nicolas, 1989; Gente et al., 1995). The study of North–South Propagating Spreading Center (NSPSC) from the North Fiji Basin (NFB) brings new insights to this debate. Basalts from the central part of the propagator have more variable incompatible and isotopic ratios then those from its northern tip. A model of dynamic partial melting of a thermally and slightly geochemically and isotopically heterogeneous mantle is proposed. Beneath the central segment, the partial fusion starts deeper (ca. 30 km) and reaches a higher rate (ca. 22%). Further open system differentiation occurs within shallow permanent magma reservoirs along most of the central segment. Below the segment closest to the tip of the propagator the partial fusion starts shallower (ca. 25 km) and stays at a lower rate (ca. 16%). The maximum of differentiation occurs close to the propagator, in small, periodically disconnected, magma bodies resulting in the production of ferrobasalts close to the tip. In order to explain these variations, the presence of an asthenospheric diapir focused beneath the central part of the NS-PSC is proposed. The petrogenetic processes of propagating spreading centers of mature oceanic basins or back-arc basins are identical.

Item Type: Article
Keywords: geochemistry, backarc basin basalts, isotopes, propagating spreading centre, Southwest Pacific, North Fiji Basin
Journal or Publication Title: Mineralogy and Petrology
Page Range: pp. 55-86
ISSN: 0930-0708
Identification Number - DOI: 10.1007/s00710-004-0061-5
Additional Information: The original publication is available at www.springerlink.com
Date Deposited: 12 Oct 2007 23:56
Last Modified: 18 Nov 2014 03:22
URI: http://eprints.utas.edu.au/id/eprint/2012
Item Statistics: View statistics for this item

Repository Staff Only (login required)

Item Control Page Item Control Page