Journal Title
Title of Journal: Contrib Mineral Petrol
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Abbravation: Contributions to Mineralogy and Petrology
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Publisher
Springer-Verlag
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Authors: Michael J Toplis William L Brown Elsa Pupier
Publish Date: 2007/09/09
Volume: 155, Issue: 3, Pages: 329-340
Abstract
The anorthite content of plagioclase grains XAn in 12 rocks from the layered series of the Skaergaard intrusion has been studied by electron microprobe typically ∼30 core and ∼70 rim analyses per thin section Mean core compositions vary continuously from An66 at the base of the layered series LZa to An32–30 at the top On the other hand crystal rims are of approximately constant composition An50 ± 1 from the LZa to the lower Middle Zone MZ Above the MZ core and rim compositions generally overlap Profiles across individual plagioclase grains from the lower zone show that most crystals have an external zone buffered at XAn ∼50 ± 1 The simplest explanation for these features is that during postcumulus crystallization in the lower zone interstitial liquids passed through a density maximum This interpretation is consistent with proposed liquid lines of descent that predict silica enrichment of the liquid associated with the appearance of cumulus magnetiteWe are particularly indebted to our friends and colleagues who generously donated rock samples before our memorable visit to the intrusion in 2001 Those people include Graham Chinner University of Cambridge Alex McBirney University of Oregon Ian Parsons Brian Upton and Peder Aspen University of Edinburgh and Kevin Walsh University of Oxford Museum Thanks also to S Barda F Diot and A Kohler of the Service Commun d’analyse of the Université Henri Poincaré in Nancy for help with the electron microprobe and SEM SA Morse and an anonymous reviewer are thanked for their comments which were greatly appreciated Financial support from the CNRSINSU “Intérieur de la Terre” and “Dyeti” programmes is also acknowledged
Keywords:
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Other Papers In This Journal:
- Precise estimation of pressure–temperature paths from zoned minerals using Markov random field modeling: theory and synthetic inversion
- Formation of cordierite-bearing lavas during anatexis in the lower crust beneath Lipari Island (Aeolian arc, Italy)
- An Early Cretaceous garnet pressure–temperature path recording synconvergent burial and exhumation from the hinterland of the Sevier orogenic belt, Albion Mountains, Idaho
- Crystal reaming during the assembly, maturation, and waning of an eleven-million-year crustal magma cycle: thermobarometry of the Aucanquilcha Volcanic Cluster
- Origin of phlogopite-orthopyroxene inclusions in chromites from the Merensky Reef of the Bushveld Complex, South Africa
- An empirical garnet (YAG) – xenotime thermometer
- Magma storage and mixing conditions for the 1953–1974 eruptions of Southwest Trident volcano, Katmai National Park, Alaska
- In situ Re–Os isotopic analysis of platinum-group minerals from the Mayarí-Cristal ophiolitic massif (Mayarí-Baracoa Ophiolitic Belt, eastern Cuba): implications for the origin of Os-isotope heterogeneities in podiform chromitites
- Reply to comments by Sengupta, Raith and Dasgupta on S. B. Bhattacharya and R. K. Kar (2002)
- Trace element mapping by LA-ICP-MS: assessing geochemical mobility in garnet
- Metasomatized lithospheric mantle beneath Turkana depression in southern Ethiopia (the East Africa Rift): geochemical and Sr–Nd–Pb isotopic characteristics
- In situ observations of bubble growth in basaltic, andesitic and rhyodacitic melts
- NanoSIMS mapping and LA-ICP-MS chemical and U–Th–Pb data in monazite from a xenolith enclosed in andesite (Central Slovakia Volcanic Field)
- Phosphorus-controlled trace element distribution in zircon revealed by NanoSIMS
- Hydroxyl in olivines from mantle xenoliths in kimberlites of the Siberian platform
- Electrical conductivity of orthopyroxene and plagioclase in the lower crust
- Chromite in komatiites: 3D morphologies with implications for crystallization mechanisms
- In situ Sr isotopic analyses of epidote: tracing the sources of multi-stage fluids in ultrahigh-pressure eclogite (Ganghe, Dabie terrane)
- Source components of the Gran Canaria (Canary Islands) shield stage magmas: evidence from olivine composition and Sr–Nd–Pb isotopes
- The stability and origin of sodicgedrite in ultrahigh-temperature Mg-Al granulites: a case study from the Gondwana suture in southern India
- The Campanian Ignimbrite (southern Italy) geochemical zoning: insight on the generation of a super-eruption from catastrophic differentiation and fast withdrawal
- Melting of clinopyroxene + magnesite in iron-bearing planetary mantles and implications for the Earth and Mars
- Immiscible separation of metalliferous Fe/ Ti-oxide melts from fractionating alkali basalt: P - T - f O2 conditions and two-liquid elemental partitioning
- Experimental calibration of a garnet–clinopyroxene geobarometer for mantle eclogites
- A case for hornblende dominated fractionation of arc magmas: the Chelan Complex (Washington Cascades)
- Melting phase relations of a mica–clinopyroxenite from the Milk River area, southern Alberta, Canada
- Shoshonite and sub-alkaline magmas from an ultrapotassic volcano: Sr–Nd–Pb isotope data on the Roccamonfina volcanic rocks, Roman Magmatic Province, Southern Italy
- The role of slab melting in the petrogenesis of high-Mg andesites: evidence from Simbo Volcano, Solomon Islands
- Evolution of the Taupo Volcanic Center, New Zealand: petrological and thermal constraints from the Omega dacite
- Multi-stage metasomatism of diamondiferous eclogite xenoliths from the Udachnaya kimberlite pipe, Yakutia, Siberia
- Hercynian, Pan-African, Proterozoic and Archean ion-microprobe zircon ages for a Betic-Rif core complex, Alpine belt, W Mediterranean – consequences for its P - T - t path
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