Titlebook: Archaean Geochemistry; The Origin and Evolu A. Kr?ner,G. N. Hanson,A. M. Goodwin Conference proceedings 1984 Springer-Verlag Berlin Heidelb

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Petrology and Geochemistry of Layered Ultramafic to Mafic Complexes from the Archaean Craton of Kared to chondrites and LREE/HREE ratios of 1–3. The patterns display weak positive Eu anomalies.The Ce./Yb. ratios correspond closely to those of Archaean layered anorthositic gabbros from Canada and West Greenlad. The late gabbros exhibit fractionated REE patterns enriched by a factor of about 40 com

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Pressures, Temperatures and Metamorphic Fluids Across an Unbroken Amphibolite Facies to Granulite Ferature in the transition zone is 750°C, determined from garnet-pyroxene Fe/Mg distributions. The quality of the geothermometry is not sufficient to establish with certainty a temperature increase southward over the transition zone..A reconnaissance profiling of the K/Rb whole rock ratios of harnock

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Origin of Archaean Charnockites from Southern India,ence, trace element distributions do not generally correlate with metamorphic grade..Geochemical modelling indicates that hornblende and/or garnet fractionation, and in some cases plagioclase fractionation, were important in the formation of the charnockite protoliths. The sparsity of mafic cumulate

FEIGN

Radiometric Ages (Rb-Sr, Sm-Nd, U-Pb) and REE Geochemistry of Archaean Granulite Gneisses from Eastd Wu 1981) or Chungtiao Movement (Huang 1978)..The granulites of the Qianxi Group have diverse compositions ranging from ultrabasic through basic-intermediate to acid. Discriminant function calculations suggest that most analyzed samples have an igneous parentage. Only a few show characteristics of

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nter-related factors: (1) advances in isotopic methods and their application to Precambrian rocks, and (2) the recognition that some of the oldest terrains have retained a wealth of primary igneous and sedi- mentary textures and even geochemical characteristics.978-3-642-70003-3978-3-642-70001-9

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cacophony

https://doi.org/10.1007/0-387-31099-1erent magma generation processes (preferred) or chemical and mineralogical stratification in the early Archaean mantle. Available Hf isotope data do not support the view that such heterogeneity in the mantle is related to core-mantle differentiation occurring ~ 4.5 Ga ago..Comparatively small-scale