Isotopic dating of the emplacement of the ultramafic masses in the Serrania de Ronda, Southern Spain

Geochemical and fluid dynamic investigations into the nature of chemical heterogeneity in the Earth's mantle

“…In addition, these ages are in agreement with Rb-Sr ages of about 22 Ma for anatectic granites associated with the peridotite massif (Loomis, 1975;Priem et al, 1979). However, the garnet-cpx pairs for R521 and R740 are different from the above ages, though they are within error of each other.…”

“…Uncertainties (2cr) are estimated at ±0.0035% and 0.5% on 143Nd/144Nd and 147Sm/144Nd, respectively, and ±0.14% and ±0.5% on 206Pb/204Pb for cpx and garnet, respectively, and 20% on 238U/204Pb. The U-Pb ages ofR618 and R256 are within error of S m-N d garnet -cpx ages from Ronda garnet peridotites and Rb-Sr dates of anatectic country rocks (Priem et al, 1979). lsochron ages of R521 and R740 are within error of each other, but outside the range of previously reported garnet-cpx Sm/Nd ages.…”

Graphite vein mineralization in the ultramafic rocks of southern Spain: Mineralogy and genetic relationships

“…Different hypotheses have been proposed to explain the emplacement of the massifs that took place about 22 Myr ago (Loomis 1972b;Priem et al 1979). Loomis (1972bLoomis ( , 1975 suggested a diapiric emplacement, produced in a single stage.…”

U/Pb zircon ages of basement gneisses and discordant felsic dykes from Vestranden, westernmost Baltic Shield and central Norwegian Caledonides

“…the compilation by KULLERUD et al, 1986). Only a few ages have been reported from Vestranden (PRIEM et al, 1968;JOHANSSON et al 1986JOHANSSON et al , 1987bTUCKER et al, 1986/87;DALLMEYER, 1988;TUCKER & KROGH, 1988;SCHOUENBORG, 1988). This paper reports four U/Pb-zircon age determinations made in order to date the Precambrian protolith rocks, to constrain the age of the earliest migmafization in the region, and to date cross-cutting, presumably late-Caledonian pegmatites.…”