Nd and Sr isotopic studies on cenozoic mafic lavas from West Antarctica: Another source for continental alkali basalts
✍ Scribed by K. Futa; W. E. Masurier
- Book ID
- 104746433
- Publisher
- Springer
- Year
- 1983
- Tongue
- English
- Weight
- 589 KB
- Volume
- 83
- Category
- Article
- ISSN
- 0010-7999
No coin nor oath required. For personal study only.
✦ Synopsis
The Nd and Sr isotopic ratios on a suite of continental alkali basalts from Marie Byrd Land, West Antarctica, define a change in the source over the range of K/Ar dates between 1 and 28 m.y. ago. The 87Sr/86Sr isotopic ratios (0.7026 to 0.703]) are unusually low for continental alkali basalts, although the corresponding ~43Nd/X44Nd ratios (0.51283 to 0.5]299) are similar to previously reported values. On a 87Sr/86Sr vs. 143Nd/144Nd diagram, they define a trend on the low 87Sr/86Sr side of the "mantle array", which has a slope steeper than the mantle array.
An explanation for the light rare earth elements (LREE) enrichment of the alkali basalts, with high 143Nd/144Nd ratios and low 87Sr/86Sr ratios, is suggested by a model which modifies the source region with a mantle-derived, CO2-enriched metasomatic fluid.