The Pasamonte unequilibrated eucrite: Pyroxene REE systematic and major-, minor-, and trace-element zoning

Details The Pasamonte unequilibrated eucrite: Pyroxene REE systematic and major-, minor-, and trace-element zoning The Pasamonte unequilibrated eucrite: Pyroxene REE systematic and major-, minor-, and trace-element zoning

Jul 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994metic..29..520p&link_type=abstract

Meteoritics (ISSN 0026-1114), vol. 29, no. 4, p. 520-521

Computer Science

2

Chondrites, Meteoritic Composition, Pyroxenes, Rare Earth Elements, Trace Elements, Electron Probes, Ion Probes, Isotopic Enrichment, Mass Spectroscopy

Scientific paper

We are evaluating the trace-element concentrations in the pyroxenes of Pasamonte. Pasamonte is a characteristic member of the main group eucrites, and has recently been re-described as a polymict eucrite. Our Pasamonte sample contained eucritic clasts with textures ranging from subophitic to moderately coarse-grained. This study concentrates on pyroxenes from an unequilibrated, coarse-grained eucrite clast. Major-, minor-, and trace-element analyses were measured for zoned pyroxenes in the eucritic clast of Pasamonte. The major- and minor-element zoning traverses were measured using the JEOL 733 electron probe with an Oxford-Link imaging/analysis system. Complemenatry trace elements were then measured for the core and rim of each of the grains by SIMS. The trace elements analyzed consisted of eight REE, Sr, Y, and Zr. These analyses were performed on a Cameca 4f ion probe. The results of the CI chondrite normalized (average CI trace-element analyses for several grains and the major- and minor-element zoning patterns from a single pyroxene grain are given. The Eu abundance in the cores of the pyroxenes represents the detection limit and therefore the (-Eu) anomaly is a minimum. Major- and minor-element patterns are typical for igneous zoning. Pyroxene cores are Mg enriched, whereas the rims are enriched in Fe and Ca. Also, Ti and Mn are found to increase, while Cr and Al generally decrease in core-to-rim traverses. The cores of the pyroxenes are more depleted in the Rare Earth Elements (REE) than the rims. Using the minor- and trace-element concentrations of bulk Pasamonte and the minor- and trace-element concentrations from the cores of the pyroxenes in Pasamonte measured in this study, we calculated partition coefficients between pyroxene and melt. This calculation assumes that bulk Pasamonte is representative of a melt composition.

Affiliated with

Also associated with

No associations

Rating

The Pasamonte unequilibrated eucrite: Pyroxene REE systematic and major-, minor-, and trace-element zoning 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 Pasamonte unequilibrated eucrite: Pyroxene REE systematic and major-, minor-, and trace-element zoning, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Pasamonte unequilibrated eucrite: Pyroxene REE systematic and major-, minor-, and trace-element zoning will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-822025