The origin of lavas and ignimbrites of the Taupo Volcanic Zone, New Zealand, in the light of oxygen isotope data

Details The origin of lavas and ignimbrites of the Taupo Volcanic Zone, New Zealand, in the light of oxygen isotope data The origin of lavas and ignimbrites of the Taupo Volcanic Zone, New Zealand, in the light of oxygen isotope data

Aug 1982

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982gecoa..46.1417b&link_type=abstract

Geochimica et Cosmochimica Acta, vol. 46, Issue 8, pp.1417-1429

Other

7

Scientific paper

The Taupo Volcanic Zone consists predominantly of andesites at each end and about a 20times larger volume of rhyolites (incl. ignimbrites and pumice) in the center. In a 18 O vs SiO 2 diagram the rhyolites do not continue the increasingly 18 O-contaminated andesite (basalt to dacite) trend, but have lower 18 O values than the most differentiated andesites. Comparison with 18 O of greywackes and conjectural granitoids seems to rule out a partial fusion origin. In retrospect the Sr isotope data of Ewart and Stipp (1968) are seen to confirm this conclusion. Isotopic adjustment of source rocks before partial fusion, by exchange with circulating subsurface waters, is highly unlikely because of the combined demands for O and Sr isotope shifts, and the constraint offered by the normal igneous to somewhat enriched 18 O values of the rhyolites. Oxygen isotope results confirm separate origins or at least different modes of ascent of basalt and andesites on one hand and rhyolites on the other. Both magma types appear to have originated below crustal formations and both have become contaminated by greywacke through which they passed to reach the surface.

Affiliated with

Also associated with

No associations

Rating

The origin of lavas and ignimbrites of the Taupo Volcanic Zone, New Zealand, in the light of oxygen isotope data 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 The origin of lavas and ignimbrites of the Taupo Volcanic Zone, New Zealand, in the light of oxygen isotope data, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The origin of lavas and ignimbrites of the Taupo Volcanic Zone, New Zealand, in the light of oxygen isotope data will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-900681