An assessment of the Th-Hf-Ta diagram as a discriminant for tectonomagmatic classifications and in the detection of crustal contamination of magmas

Details An assessment of the Th-Hf-Ta diagram as a discriminant for tectonomagmatic classifications and in the detection of crustal contamination of magmas An assessment of the Th-Hf-Ta diagram as a discriminant for tectonomagmatic classifications and in the detection of crustal contamination of magmas

Oct 1980

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1980e%26psl..50....1t&link_type=abstract

Earth and Planetary Science Letters, Volume 50, Issue 1, p. 1-10.

Other

4

Scientific paper

The Th-Hf-Ta diagram, recently proposed [1] as a means of discriminating basalts erupted in various tectonic environments and of detecting crustal contamination in such magmas, is shown to be unsatisfactory for both of its stated purposes. Data are presented for Th, Hf, Ta, Sr and Sr- and Pb-isotopes in basic lavas and a dolerite sill from the ensialic British Tertiary Volcanic Province (BTVP). Taken in conjunction with published results, the isotopic ratios show that some of the BTVP basic magmas are essentially uncontaminated by continental crust, except for the selective introduction of small variable amounts of unradiogenic Pb. Those BTVP magmas which show appreciable isotopic contamination have interacted with either upper or lower crust, or both. Th/(Hf + Ta) is insensitive to contamination with the Th-poor lower crust of cratons but rises during gross contamination with Th-rich upper crust. BTVP basic magmas containing negligible to moderate crustal isotopic components plot in the field of the Th-Hf-Ta diagram occupied by ``normal'' mid-ocean ridge basalts. Other volcanic provinces of known tectonic setting which plot wholly or partially outside their appropriate fields on the Th-Hf-Ta diagram are: the Hawaii-Emperor Seamount Chain, the Snake River Plain (Idaho, U.S.A.), the Azores and the Gregory Rift (Kenya).

Affiliated with

Also associated with

No associations

Rating

An assessment of the Th-Hf-Ta diagram as a discriminant for tectonomagmatic classifications and in the detection of crustal contamination of magmas 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 An assessment of the Th-Hf-Ta diagram as a discriminant for tectonomagmatic classifications and in the detection of crustal contamination of magmas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An assessment of the Th-Hf-Ta diagram as a discriminant for tectonomagmatic classifications and in the detection of crustal contamination of magmas will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-948110