Rubidium, strontium content and strontium isotopic composition of strongly alkalic basaltic rocks from the Cape Verde islands
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چکیده
منابع مشابه
Isotopic composition of strontium in volcanic rocks from oahu.
Analysis of several well-documented specimens from each of the three volcanic series on Oahu gives the following mean ratios of Sr(87) to Sr(86): the Waianae series, 0.7030 +/- 0.00010 (sigma); the Koolau series, 0.70385+/- 0.00009 (sigma); and the Honolulu series, 0.7029 ++/- 0.00006 ( sigma). The mean ratio of Sr(87) to Sr(86) of the Koolau series specimens is significantly higher than the me...
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The carbonatite problem can be stated as follows: Are carbonatites genetically related to sedimentary carbonate rocks, or are they derived from a silicate parent material? The isotopic composition of strontium in 21 carbonatites and in several related alkaline rocks has been determined. The mean Sr87/$r86 ratio for the 21 carbonatites is 0.7065 + 0.0003. The Sr87/sr86 ratios of sedimentary carb...
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The rubidium-strontium isotopic relationships in alkaline and subalkaline oceanic basalts have been determined by mass spectrometric techniques. The results are consistent with a complex model for the earth in which there is continuing convection. Sr87/Sr 8 6 ratios for all oceanic basalts fall in a narrow range from .702 to .705. This suggests that the oceanic upper mantle source regions are g...
متن کاملLeprosy in the Cape Verde Islands.
The Cape Verde Islands are located in the Atlantic Ocear. ) ' �45 km off the coast of Senegal . Ten islands and 5 islets, between 1 7° 1 2 ' 5 & 1 4° 1 8 ' N. an d 22°44' & 2 5 ° 2 2 ' W. , they are divided into 2 groups : Barlavento , North, 6 islan ds , and Sotavento , South , 4 islands . Total area is 4 . 0 3 3 km2 • Three of the islan ds , closer to the African continent , are sandy and fla...
متن کاملStrontium Isotopic Anomalies in the Allende Meteorite
We report Sr isotope anomalies in two Ca·Al-rich inclusions (EKl-4-1 and Cl) of the Allende meteoritewhichalsocontainanomaliesin 0, Mg, Ca, Ba, Nd and Sm. The Sr effects correspond to 84 Sr or 88 Sr deficits of 3.2"too and 0.8%o or to 86 Sr excesses of 1.6%o and 0.4"too. Although it cannot be ascertained in which isotope the anomalies reside, arguments based on the 8 7 Sr abundance indicate tha...
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ژورنال
عنوان ژورنال: Contributions to Mineralogy and Petrology
سال: 1974
ISSN: 0010-7999,1432-0967
DOI: 10.1007/bf00371163