East pacific ridge (2°S-19°S) versus nazca intraplate volcanism: rare-earth evidence
Schilling, J.-G.; Bonatti, E. (1975). East pacific ridge (2°S-19°S) versus nazca intraplate volcanism: rare-earth evidence. Earth Planet. Sci. Lett. 25(2): 93-102
In: Earth and Planetary Science Letters. Elsevier: Amsterdam. ISSN 0012-821X; e-ISSN 1385-013X, more
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Authors | | Top |
- Schilling, J.-G.
- Bonatti, E.
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Abstract |
Basalts from seamounts within the Nazca Plate representing intraplate volcanism, and the East Pacific Ridge between 19°S and 2°N have similar light rare earth depleted abundance patterns. Both intraplate and ridge basalts appear to have been derived from the low-velocity layer apparently depleted in large lithophile elements (DLVL). Nepheline-normative basalts and ferrobasalts occasionally occurring on the East Pacific Rise are shown to have also been derived from the same DLVL source. Furthermore, the rare-earth pattern similarity of nepheline-normative and tholeiitic basalts from the East Pacific Rise is best explained by distinct, pressure induced, conditions of partial melting of the DLVL source; whereas total rare-earth pattern enrichment and relative europium depletion of the ferrobasalts are consistent with shallow depth fractional crystallization during ascent. |
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