scholarly journals Primary Melt Inclusions in Eclogite Diamonds and their Genetic Implication

2019 ◽  
Keyword(s):  
Melt Inclusions ◽  
Genetic Implication ◽  
Primary Melt

scholarly journals Silicate Melt Inclusions in Diamonds of Eclogite Paragenesis from Placers on the Northeastern Siberian Craton

Minerals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 412 ◽  
Author(s):  
Vladislav Shatsky ◽  
Dmitry Zedgenizov ◽  
Alexey Ragozin ◽  
Viktoriya Kalinina
Keyword(s):  
Melt Inclusions ◽  
Silicate Melt ◽  
Aggregation State ◽  
Cooling Stage ◽  
Spectroscopic Analyses ◽  
New Findings ◽  
High Degree ◽  
Raman Spectral ◽  
Raman Spectral Analysis ◽  
Primary Melt

New findings of silicate-melt inclusions in two alluvial diamonds (from the Kholomolokh placer, northeastern Siberian Platform) are reported. Both diamonds exhibit a high degree of N aggregation state (60–70% B) suggesting their long residence in the mantle. Raman spectral analysis revealed that the composite inclusions consist of clinopyroxene and silicate glass. Hopper crystals of clinopyroxene were observed using scanning electron microscopy and energy-dispersive spectroscopic analyses; these are different in composition from the omphacite inclusions that co-exist in the same diamonds. The glasses in these inclusions contain relatively high SiO2, Al2O3, Na2O and, K2O. These composite inclusions are primary melt that partially crystallised at the cooling stage. Hopper crystals of clinopyroxene imply rapid cooling rates, likely related to the uplift of crystals in the kimberlite melt. The reconstructed composition of such primary melts suggests that they were formed as the product of metasomatised mantle. One of the most likely source of melts/fluids metasomatising the mantle could be a subducted slab.

Near-primary melt inclusions in anorthite phenocrysts from the Galapagos Platfrom

1993 ◽  
Vol 119 (4) ◽  
pp. 527-537 ◽  
Author(s):  
Chris W. Sinton ◽  
David M. Christie ◽  
Valerie L. Coombs ◽  
Roger L. Nielsen ◽  
Martin R. Fisk
Keyword(s):  
Melt Inclusions ◽  
Primary Melt

scholarly journals Formation Mechanism of the Velyka Vyska Syenite Massif (Korsun-Novomyrhorod Pluton, Ukrainian Shield) Derived from Melt Inclusions in Zircon

2021 ◽  
Vol 43 (1) ◽  
pp. 3-15
Author(s):  
D.K. VOZNYAK ◽  
E.V. ., LEVASHOVA ◽  
S.G. SKUBLOV ◽  
S.G. KRYVDIK ◽  
O.A. VYSHNEVSKYI ◽  
...  
Keyword(s):  
High Pressure ◽  
Melt Inclusions ◽  
Ore Deposits ◽  
Partial Replacement ◽  
Type I ◽  
High Grade ◽  
Ree Distribution ◽  
The Matrix ◽  
Homogenization Temperatures ◽  
Primary Melt

The formation of leucosyenites in the Velyka Vyska syenite massif was provoked by the liquation layering of magmatic melt. This assumption is based on the presence of two primary melt inclusions of different chemical composition in zircon crystals from Velyka Vyska leucosyenites. They correspond to two types of silicate melts. Type I is a leucosyenite type that contains high SiO2 concentrations (these inclusions dominate quantitatively); type II is a melanosyenite type that contains elevated Fe and smaller SiO2 concentrations. The liquation layering of magmatic melt was slow because the liquates are similar in density; leucosyenite melt, which is more abundant than melt of melanosyenite composition, displays greater dynamic viscosity; the initial sizes of embryos of melanosyenite composition are microscopic. Sulphide melt, similar in composition to pyrrhotite, was also involved in the formation of the massif. Zircon was crystallized at temperatures over 1300°С, as indicated by the homogenization temperatures of primary melt inclusions. The REE distribution spectra of the main parts (or zones,) of zircon crystals from the Velyka Vyska massif are identical to those of zircon from the Azov and Yastrubets syenite massifs with which high-grade Zr and REE (Azov and Yastrubets) ore deposits are associated. They are characteristic of magmatically generated zircon. Some of the grains analyzed contain rims that are contrasting against the matrix of a crystal, look dark-grey in the BSE image and display flattened REE distribution spectra. Such spectra are also typical of baddeleyite, which formed by the partial replacement of zircon crystals. The formation of a dark-grey rim in zircon and baddeleyite is attributed to the strong effect of high-pressure СО2-fluid on the rock. The formation patterns of the Velyka Vyska and Azov massifs exhibit some common features: (а) silicate melt liquation; (b) high ZrO2 concentrations in glasses from hardened primary melt inclusions; (c) the supply of high-pressure СО2-fluid flows into Velyka Vyska and Azov hard rocks. Similar conditions of formation suggest the occurrence of high-grade Zr and REE ores in the Velyka Vyska syenite massif.

Tin and associated metal and metalloid geochemistry by femtosecond LA-ICP-QMS microanalysis of pegmatite–leucogranite melt and fluid inclusions: new evidence for melt–melt–fluid immiscibility

2012 ◽  
Vol 76 (1) ◽  
pp. 91-113 ◽  
Author(s):  
A. Y. Borisova ◽  
R. Thomas ◽  
S. Salvi ◽  
F. Candaudap ◽  
A. Lanzanova ◽  
...  
Keyword(s):  
Fluid Inclusions ◽  
Inductively Coupled Plasma ◽  
Melt Inclusions ◽  
Saturation Index ◽  
Femtosecond Laser Ablation ◽  
Type A ◽  
Inductively Coupled ◽  
Melt And Fluid Inclusions ◽  
Layer Effect ◽  
Primary Melt

AbstractGranitic pegmatites are exceptional igneous rocks and the possible role of an immiscibility process in their origin is strongly debated. To investigate metal and metalloid behaviour in hydrous peraluminous systems (aluminium saturation index, ASI >1), we analysed 15 quartz-hosted primary melt and fluid inclusions from pegmatites in the Ehrenfriedersdorf Complex (Erzgebirge, Germany) and 26 primary melt inclusions from leucogranites of the Ehrenfriedersdorf district (Germany), Kymi (Finland) and Erongo (Namibia) by femtosecond laser ablation inductively coupled plasma quadrupole mass spectrometry. The results presented here for 32 elements provide evidence for metal and metalloid fractionation between two types of immiscible melts (A and B) and NaCl – HCl-rich brine in the pegmatite system. No evidence for the boundary layer effect was observed in the 40 – 500 μm size melt inclusions that were investigated. The data on the Ehrenfriedersdorf pegmatites allow quantification of the metal and metalloid partitioning between natural NaCl-rich brine and the two types of melt (e.g. KAsbrine/type-A,B melts = 0.01 – 1.7; KSbbrine/type-A,B melts = 10 – 285; KZnbrine/type-A,B melts ≥ 50; KPbbrine/type-A melt ≥ 50; KAgbrine/type-A melt = 46). These data are in accord with existing natural and experimental data on equilibrium fluid – melt partitioning as well as spectroscopic data on the metal and metalloid complexation in hydrous aluminosilicate melts and NaCl – HCl-rich fluids.

A siliceous komatiitic source of Bushveld magmas revealed by primary melt inclusions in olivine

Lithos ◽  
2021 ◽  
Vol 388-389 ◽  
pp. 106094
Author(s):  
I.P. Solovova ◽  
M.A. Yudovskaya ◽  
J.A. Kinnaird ◽  
A.H. Wilson ◽  
N.G. Zinovieva
Keyword(s):  
Melt Inclusions ◽  
Primary Melt

scholarly journals Two Contrasting H2O-rich Components in Primary Melt Inclusions from Mount Shasta

2010 ◽  
Vol 51 (7) ◽  
pp. 1571-1595 ◽  
Author(s):  
M. Le Voyer ◽  
E. F. Rose-Koga ◽  
N. Shimizu ◽  
T. L. Grove ◽  
P. Schiano
Keyword(s):  
Melt Inclusions ◽  
Primary Melt

scholarly journals Three-dimensional distribution of primary melt inclusions in garnets by X-ray microtomography

2018 ◽  
Vol 103 (6) ◽  
pp. 911-926 ◽  
Author(s):  
Matteo Parisatto ◽  
Alice Turina ◽  
Giuseppe Cruciani ◽  
Lucia Mancini ◽  
Luca Peruzzo ◽  
...  
Keyword(s):  
Melt Inclusions ◽  
Three Dimensional ◽  
X Ray ◽  
Dimensional Distribution ◽  
Primary Melt

Crustal anatexis and melt extraction during deformation in the restitic xenoliths at El Joyazo (SE Spain)

1997 ◽  
Vol 61 (404) ◽  
pp. 15-27 ◽  
Author(s):  
B. Cesare ◽  
E. Salvioli Mariani ◽  
G. Venturelli
Keyword(s):  
Melt Inclusions ◽  
Crustal Anatexis ◽  
Se Spain ◽  
Widespread Occurrence ◽  
Melt Extraction ◽  
Mineral Phases ◽  
Interstitial Glass ◽  
High Grade Metamorphism ◽  
Representative Samples ◽  
Primary Melt

AbstractThe dacite of El Joyazo contains abundant metapelitic xenoliths. These can be divided into two main types: garnet-biotite-sillimanite and spinel-cordierite xenoliths. In the xenoliths the widespread occurrence of rhyolitic glass as interstitial films, foliation-parallel layers and primary melt inclusions in all mineral phases indicates that these assemblages developed in the presence of a melt phase, i.e. during anatexis. The composition of the interstitial glass is comparable to that of the melt inclusions, suggesting that melt was locally produced. Phase equilibria indicate that anatexis occurred at P-T conditions of 5–7 kbar and 850±50°C.Several microstructural lines of evidence show that melt extraction was assisted by deformation during foliation development, and that on the scale of the xenoliths (up to 50 cm) melt escaped mainly by flow along foliation planes. The development of a syn-anatectic foliation also suggests that metapelitic rocks were involved in high-grade metamorphism and partial melting prior to fragmentation and dispersion in the host dacite.Mass balance calculations, based on the chemical composition of interstitial glass and melt inclusions in minerals, the bulk xenoliths and representative samples of potential pelitic sources support a model wherein the xenoliths represent restites after the extraction of 30 to 55 wt.% melt from graphitic metapelite protoliths similar to the rocks constituting the surrounding Alpujarride metamorphic complex.

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