Crustal contamination of mafic magmas: evidence from a petrological, geochemical and Sr-Nd-Os-O isotopic study of the Proterozoic Isortoq dike swarm, South Greenland
Lithos. Bd. 74. H. 3-4. 2004 S. 199 - 232
Erscheinungsjahr: 2004
ISBN/ISSN: 0024-4937
Publikationstyp: Zeitschriftenaufsatz
Sprache: Englisch
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Inhaltszusammenfassung
The mid-Proterozoic Isortoq dike swarm in the Gardar Province, South Greenland, comprises a variety of alkaline rocks ranging from gabbroic to syenitic in composition. Major magmatic mineral phases are olivine, clinopyroxene, Fe-Ti oxides, amphibole, plagioclase and alkali feldspar. Quartz occurs in some samples as a late magmatic phase. Liquidus temperatures of olivine-bearing samples range between 1120 and 1145 degreesC and solidus temperatures are 850-930 degreesC. Calculated silica activi...The mid-Proterozoic Isortoq dike swarm in the Gardar Province, South Greenland, comprises a variety of alkaline rocks ranging from gabbroic to syenitic in composition. Major magmatic mineral phases are olivine, clinopyroxene, Fe-Ti oxides, amphibole, plagioclase and alkali feldspar. Quartz occurs in some samples as a late magmatic phase. Liquidus temperatures of olivine-bearing samples range between 1120 and 1145 degreesC and solidus temperatures are 850-930 degreesC. Calculated silica activities are highly variable between 0.53 and unity. Oxygen fugacities vary from -3 to +1 log units relative to the fayalite-magnetite-quartz buffer. The rocks have MgO contents » weiterlesen» einklappen
Autoren
Klassifikation
DFG Fachgebiet:
3.42 - Geologie und Paläontologie
DDC Sachgruppe:
Geowissenschaften
