Evidence for crustal assimilation, mixing of magmas, and a 87 Sr-rich upper mantle; an oxygen and strontium isotope study of the M. Vulsini volcanic area, central Italy

Saved in:
Authors:Ferrara, G.; Preite Martinez, M.; Taylor, H. P.; Tanarini, S.; Turi, Bruno
Author Affiliations:Primary:
Ist. Geochronol. Isot. Geochem., C.N.R., I-56100 Pisa, Italy
Volume Title:Contributions to Mineralogy and Petrology
Source:Contributions to Mineralogy and Petrology, 92(3), p.269-280. Publisher: Springer International, Heidelberg-New York, International. ISSN: 0010-7999
Publication Date:1986
Note:In English. 33 refs.; illus. incl. 1 table, geol. sketch map
Summary:O, Sr and chemical analyses made on 39 lavas and ignimbrites from M. Vulsini, in the N of the K-rich Quaternary Roman province, show that the rocks belong mainly to the undersaturated, leucite- bearing (high-K) series, but also include some samples from the minor SiO2-saturated, hypersthene-(quartz)-normative (low-K) series. The effects of post-eruption alteration on delta 18O values were taken into account but because Sr is high, alteration had little effect on the Sr ratios at M. Vulsini. The 87Sr/86Sr = 0.7097-0.7168 and delta 18O = 65-13.8 which is on average the highest in the province, probably because it is one of the sites of greatest crustal assimilation and hybridism between K-rich Roman magmas and SiO2-rich Tuscan anatectic magmas. The high-K series must have originated from an upper mantle source region enriched in 87Sr and LIL elements, and the O and Sr ratios are identical to the parent magma at Alban Hills, 120 km S. The low-K series originated from a lower 87Sr source region. The same relationship is found elsewhere in Italy where the two magmas coexist. [R.E.S.]
Subjects:Alkaline earth metals; Assimilation; Chemical composition; Crust; Geochemistry; Igneous rocks; Ignimbrite; Isotopes; Lava; Magmas; Magmatic associations; Mantle; Metals; Mixing; O-18/O-16; Oxygen; Petrology; Pyroclastics; Sr-87/Sr-86; Stable isotopes; Strontium; Upper mantle; Volcanic rocks; Europe; Italy; Latium Italy; Southern Europe; Central Italy; Mount Vulsini
Abstract Numbers:86M/4648
Record ID:1988053906
Copyright Information:GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from Mineralogical Abstracts, United Kingdom, Twickenham, United Kingdom, Reference includes data from Geoline, Bundesanstalt fur Geowissenschaften und Rohstoffe
Tags: Add Tag
No Tags, Be the first to tag this record!
Be the first to leave a comment!
You must be logged in first