Hydrated Peridotite–Basaltic Melt Interaction Part II: Fast Assimilation of Serpentinized Mantle by Basaltic Magma

Kinetics of pyrope megacryst reactions in ascending basaltic magma – relevance to high-pressure magmatic crystallization at Elie Ness, East Fife

Geological Magazine ◽

10.1017/s0016756800030752 ◽

1984 ◽

Vol 121 (6) ◽

pp. 615-620 ◽

Cited By ~ 6

Author(s):

Colin H. Donaldson

Keyword(s):

High Pressure ◽

Phase Equilibria ◽

Crystallization Temperature ◽

Basaltic Magma ◽

Basaltic Melt ◽

The Stability ◽

Kinetics Of

AbstractThe rates of resorption of pyrope in basaltic melt and of pyrope decomposition to pyroxene + melt at pressures below the stability of garnet are used to examine the proposition (Chapman, 1976) that pyrope megacrysts in the Elie Ness neck began ascent from the mantle at 1300–1450°C. Both reactions are extremely rapid at these temperatures and yet the petrographic evidence is that neither occurred. Either the transporting magma cooled extremely rapidly during ascent (> 30000 °/h) or, more likely, was considerably cooler than previously proposed. Water was a significant constituent of the magma, and a crystallization temperature for the garnet of as little as 1000 °C is possible, based on existing phase–equilibria data.

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The Kræmer Ø syenite, Kangerdlugssuaq: preliminary description of one of the voluminous oversaturated syenites of the East Greenland Tertiary

Bulletin of the Geological Society of Denmark ◽

10.37570/bgsd-1990-38-13 ◽

1991 ◽

Vol 38 ◽

pp. 145-151

Author(s):

C. K. Brooks

Keyword(s):

Main Part ◽

Basaltic Magma ◽

Coarse Grained ◽

Skaergaard Intrusion ◽

East Greenland ◽

Partial Melt ◽

Basaltic Melt ◽

Basaltic Magmas ◽

Modal Layering ◽

Preliminary Description

Tue Kræmer Ø syenite, situated close to the Skaergaard intrusion, is typical of many oversturated syenites in the area. It consists of a maginal breccia with a sharp contact to the surrounding gneisses. This breccia, about 150 m wide is made up of basaltic clasts in a granitic matrix. It is associated with pegmatites, aplites and granophyres, all with a non-peralkaline characters. Tue main part of the syenite is a coarse-grained, massively jointed body with many large basic xenoliths and occasional modal layering. It is associated with peralkaline rhyolitic dikes and pegmatites. Anatexis of basement and crystal differentiation from a basaltic magma are thought to be unlikely processes to explain the origin of the syenites although the breccia matrix appears to be a simple partial melt of the gneisses. It is postulated thai such an anatectic melt, formed by heat transfer from basaltic magmas, becomes modified by diffusive interchange with the basaltic melt to generate the syenite in the way described for a nearby locality by Nielsen & Brooks (1988).

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Major and trace elements geochemistry of basalts and trachyphonolites from Huahine Island, Society archipelago (French Polynesia)

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.177.4.179 ◽

2006 ◽

Vol 177 (4) ◽

pp. 179-190 ◽

Cited By ~ 1

Author(s):

Luc Harnois ◽

Ross K. Stevenson

Keyword(s):

Trace Elements ◽

Rare Earth ◽

Basaltic Magma ◽

French Polynesia ◽

Major And Trace Elements ◽

Major Elements ◽

Trace Element Data ◽

Chemical Variability ◽

Basaltic Melt ◽

Heterogeneous Source

Abstract Basalts and trachyphonolites from Huahine Island (Society archipelago) have been analyzed for major elements and several trace elements (including rare earth elements). Eight basalts from the nearby Bora Bora Island were also analyzed for comparison. Ni-MgO, Ni-Ba, and Ni-Rb modeling indicates that the abundances of these elements in Huahine basalts cannot be entirely the result of crystallization and/or accumulation of olivine and reflect a variability already present in a heterogeneous source, a conclusion supported by Pb and Ce data. The chemical variability of Huahine basalts, with respect to several trace elements, can be explained by contamination of the differentiating basaltic melt by a sedimentary reservoir. The same trace element data also suggest that Huahine trachyphonolites can be derived from basaltic magma by assimilation-fractional crystallization or from partial melting of a hawaiite.

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ORIGIN OF GIANT PLAGIOCLASE IN A LARGE-VOLUME BASALTIC MAGMA: ENTRAINMENT OF PARTIALLY-MELTED GABBROIC CUMULATE IN THE STEENS BASALT, SE OREGON, USA

10.1130/abs/2017am-307071 ◽

2017 ◽

Author(s):

Conner H. Toth ◽

◽

Wendy A. Bohrson ◽

Mikkel Louis ◽

Sylvana Bendaña ◽

...

Keyword(s):

Large Volume ◽

Basaltic Magma ◽

Steens Basalt

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BASALTIC MAGMA GENESIS AND MANTLE SOURCES BENEATH TWO CENOZOIC VOLCANOES, MT. EARLY AND SHERIDAN BLUFF, EAST ANTARCTICA

10.1130/abs/2020am-353988 ◽

2020 ◽

Author(s):

Yuyu Li ◽

◽

K.S. Panter ◽

John L. Smellie ◽

Jerzy S. Blusztajn ◽

...

Keyword(s):

Basaltic Magma ◽

East Antarctica ◽

Magma Genesis ◽

Mantle Sources

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In situ quantification of crystallisation kinetics of plagioclase and clinopyroxene in basaltic magma: Implications for lava flow

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2021.117016 ◽

2021 ◽

Vol 568 ◽

pp. 117016

Author(s):

Nolwenn Le Gall ◽

Fabio Arzilli ◽

Giuseppe La Spina ◽

Margherita Polacci ◽

Biao Cai ◽

...

Keyword(s):

Lava Flow ◽

Basaltic Magma ◽

Crystallisation Kinetics ◽

Kinetics Of

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XXII.—The Petrology of Picritic Rocks in Minor Intrusions—a Hebridean Group

Transactions of the Royal Society of Edinburgh ◽

10.1017/s0080456800003112 ◽

1959 ◽

Vol 63 (3) ◽

pp. 459-499 ◽

Cited By ~ 28

Author(s):

H. I. Drever ◽

R. Johnston

Keyword(s):

Source Rock ◽

Rock Type ◽

Basaltic Magma ◽

Ultrabasic Rock ◽

Working Hypothesis ◽

Selective Fusion ◽

Rich Liquid ◽

Factual Data

SynopsisThe results are presented of a detailed petrological reconnaissance of a group of picritic minor intrusions in the Hebrides. A substantial amount of new factual data is subjected to a unified treatment as a basis for reference and discussion. Olivine phenocrysts are not appreciably zoned and there is no evidence that they have a reaction relation with the liquid represented by the groundmass. Variations in the size and amount of olivine in individual intrusions are examined in detail and attributed to composite intrusion of differentiated material. A distinctive non-porphyritic facies found in several sills and in one dyke is chemically analyzed. Four analyses from widely separated localities establish this facies as a remarkably invariant, eucritic rock-type. The composition of the groundmass of the picritic rocks is variable and there is no evidence whatever of the participation of basaltic magma in their formation. Although no attempt is made to explain the new data in detail, a comprehensive working hypothesis is formulated. The origin of such picritic intrusions is believed to be due to selective fusion of pre-existing ultrabasic rock. Liquid more basic than normal basalt magmas can be formed by this process. Some re-precipitation of olivine may have preceded final emplacement of a magnesia-rich liquid which contained xenocrysts, mainly of olivine, from the source rock.

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