Computer Science
Scientific paper
May 1969
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1969gecoa..33..543s&link_type=abstract
Geochimica et Cosmochimica Acta, vol. 33, Issue 5, pp.543-553
Computer Science
4
Scientific paper
Detailed study of the strontium isotopic composition of closely associated alpine-type ultramafic intrusions in western North Carolina has revealed variable but high 87 Sr / 86 Sr ratios, similar to those found in previous reconnaissance studies. Because of the relatively wide variations in 87 Sr / 86 Sr ratios on a local scale and the lack of isochron relationships, it seems that radiogenic strontium may have been introduced into the ultramafic intrusions, in most cases without significant alteration of the primary silicate minerals. The intrusion of pegmatites into the ultramafics and country rock about 350 m.y. ago is a likely source of secondary radiogenic strontium. Investigation of the distribution of K, Rb and Sr within the mineral phases of ultramafic rocks has indicated that the concentration of strontium is critically controlled by the amount of diopside present. The absolute abundance levels of all three elements are generally higher in minerals separated from a basaltic ultramafic nodule than in those separated from alpine-type intrusions. The K / Rb ratios of the alpine-type ultramafic rocks bear no systematic relationship to K content. If each ultramafic sample is considered as a separate system, however, the K / Rb ratios increase with increasing K content and in the order olivine to enstatite to diopside, in every case. This relationship was not found for minerals separated from the basalt nodule.
No associations
LandOfFree
Abundances of K, Rb, Sr and Sr isotopes in ultramafic rocks and minerals from western North Carolina 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 Abundances of K, Rb, Sr and Sr isotopes in ultramafic rocks and minerals from western North Carolina, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Abundances of K, Rb, Sr and Sr isotopes in ultramafic rocks and minerals from western North Carolina will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1390047