Uranium content, distribution, and migration in the Glendessarry syenite, Inverness-shire

1981 ◽  
Vol 44 (336) ◽  
pp. 443-448 ◽  
Author(s):  
M. B. Fowler
Keyword(s):  
Late Stage ◽  
Fission Track ◽  
Content Distribution ◽  
Fluid Phase ◽  
Uranium Content ◽  
Rich Phase ◽  
Accessory Minerals ◽  
Track Method ◽  
Metamorphic Fluids ◽  
And Migration

AbstractThe distribution of uranium in a suite of variably deformed and metamorphosed rocks from the leucocratic member of the Glendessarry syenite has been determined using the fission track method. The uranium content of the magma increased during crystallization and uranium was concentrated in accessory minerals such as monazite, zircon, sphene, allanite, apatite, and microinclusions of a Zr- and Ti-rich phase. Contamination of the magma by pelitic metasediment enhanced the uranium content and monazite and zircon formed instead of sphene, allanite, and apatite.Evidence of subsolidus uranium mobility in late stage magmatic or metamorphic fluids is presented here and shows: (a) Intracrystalline redistribution of uranium, especially in grains of sphene. (b) Intergranular mobility in a fluid phase, which affected the uraniferous accessory minerals in several ways.

Pétrologie du granite peralcalin du lac Brisson, Labrador central, Nouveau-Québec. II. Minéralogie et modalités de cristallisation

1993 ◽  
Vol 30 (12) ◽  
pp. 2423-2435 ◽  
Author(s):  
D. Pillet ◽  
M. Chenevoy ◽  
M. Bélanger
Keyword(s):  
Late Stage ◽  
Fluid Phase ◽  
Alkali Feldspar ◽  
Stability Field ◽  
Residual Liquid ◽  
Accessory Minerals ◽  
Mafic Mineral ◽  
Peralkaline Granite ◽  
Zirconium Silicate

Mineral zonation in the Québec–Labrador Brisson Lake peralkaline granite displays quartzose and feldspathic lithofacies arranged concentrically, the latter occupying the centre of the intrusion. The zonation is the result of successive magmatic pulses. In the feldspathic facies, agpaitic crystallization began under hypersolvus conditions around 720 °C with PF = 0.1 GPa. Subsolvus crystallization involving enrichment of the residual liquid in F continued to below 500 °C. The quartzose facies is more differentiated and its composition was controlled by feldspar fractionation. Early quartz crystallization is partly explained by the high content of F in the magma. The mafic mineral succession is, in both facies: Li- and Zn-rich arfvedsonite with an important ferrorichtérite component, which crystallized along with alkali feldspar under low [Formula: see text]; aenigmatite contemporary of amphibole or anterior, destabilized to form neptunite, astrophyllite, aegirine, or arfvedsonite; primary titaniferous aegyrine, contemporary with the amphibole and replaced by secondary aegyrine; neptunite and astrophyllite replacing aenigmatite. This succession is in accordance with the increase of Na and F in the fluid phase, and the increase of [Formula: see text] near the end of crystallization. Among the accessory minerals, euhedral zircon is indicative of the initial richness of the magma in Zr. Magmatic vlasovite, and elpidite formed from late fluid, are evidence that residual system entered the zirconium silicate stability field. Zircon with a fibrous, radiating texture, and gittinsite are indicative of the postmagmatic evolution of the pluton and the presence of a late stage residual fluid which was enriched in Ca and Sr.

scholarly journals Expression of wild-type and mutated rabbit osteopontin in Escherichia coli, and their effects on adhesion and migration of P388D1 cells

1995 ◽  
Vol 307 (1) ◽  
pp. 257-265 ◽  
Author(s):  
K Nasu ◽  
T Ishida ◽  
M Setoguchi ◽  
Y Higuchi ◽  
S Akizuki ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Fluid Phase ◽  
Intradermal Injection ◽  
Polymorphonuclear Leucocyte ◽  
Alpha Subunit ◽  
Wild Type ◽  
Alpha Subunits ◽  
Leucocyte Migration ◽  
And Migration ◽  
Chemotactic Effect

Recombinant wild-type rabbit osteopontin (rOP) and the protein with an aspartate-to-glutamate transposition induced by a point mutation in the rabbit OP cDNA within the Gly-Arg-Gly-Asp-Ser (GRGDS) sequence were expressed in Escherichia coli and purified to homogeneity. P388D1 cells bound rOP in a saturable manner. rOP induced adhesion and haptotaxis of P388D1 cells, whereas mutated rabbit OP (rOPmut) did not. Anti-rOP IgG F(ab′)2 and synthetic GRGDS peptide inhibited rOP-mediated adhesion and haptotaxis of P388D1 cells. Fibronectin (FN)-mediated adhesion of P388D1 cells was markedly inhibited in the presence of fluid-phase rOP. Adhesion of P388D1 cells to rOP was significantly inhibited by anti-[alpha-subunits of VLA4 (alpha 4) and VLA5 (alpha 5)] monoclonal antibodies (mAbs), but not by anti-[alpha-subunit of vitronectin (VN) receptor (alpha V) or Mac-1 (alpha M)] mAb. Adhesion of P388D1 cells to FN and VN was significantly inhibited by anti-alpha V mAb but not anti-alpha 4, -alpha 5 or -alpha M mAb. Haptotaxis of P388D1 cells to rOP was significantly inhibited by anti-alpha V mAb, but not by anti-alpha 4, -alpha 5 and alpha M mAbs, whereas that to FN showed no inhibition with all three mAbs. Haptotaxis of P388D1 cells to VN was significantly inhibited by anti-alpha 5 and -alpha V mAbs but not by anti-alpha 4 and -alpha M mAbs. Similar features of inhibition of adhesion and haptotaxis of P388D1 cells to human OP were observed by mAbs. rOP had no chemotactic effect on P388D1 cells. Significant polymorphonuclear leucocyte migration was observed 3-12 h after intradermal injection of rOP into rabbits.

Effects of Etching on Zircon Grains and its Implications for the Fission Track Method

2012 ◽  
Vol 66 (5) ◽  
pp. 545-551 ◽  
Author(s):  
Carlos Alberto Tello Sáenz ◽  
Eduardo Augusto Campos Curvo ◽  
Airton Natanael Coelho Dias ◽  
Cleber José Soares ◽  
Carlos José Leopoldo Constantino ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Crystal Lattice ◽  
Fission Track ◽  
Surface Characteristics ◽  
Optical Microscope ◽  
Etching Time ◽  
X Ray ◽  
Track Method ◽  
Zircon Fission Track ◽  
Natural Zircon

Studies of zircon grains using optical microscopy, micro-Raman spectroscopy, and scanning electron microscopy (SEM) have been carried out to characterize the surface of natural zircon as a function of etching time. According to the surface characteristics observed using an optical microscope after etching, the zircon grains were classified as: (i) homogeneous; (ii) anomalous, and (iii) hybrid. Micro-Raman results showed that, as etching time increases, the crystal lattice is slightly altered for homogeneous grains, it is completely damaged for anomalous grains, and it is altered in some areas for hybrid grains. The SEM (energy dispersive X-ray spectroscopy, EDS) results indicated that, independent of the grain types, where the crystallinity remains after etching, the chemical composition of zircon is approximately 33% SiO2:65% ZrO2 (standard natural zircon), and for areas where the grain does not have a crystalline structure, there are variations of ZrO2 and, mainly, SiO2. In addition, it is possible to observe a uniform surface density of fission tracks in grain areas where the determined crystal lattice and chemical composition are those of zircon. Regarding hybrid grains, we discuss whether the areas slightly altered by the chemical etching can be analyzed by the fission track method (FTM) or not. Results of zircon fission track and U-Pb dating show that hybrid and homogeneous grains can be used for dating, and not only homogeneous grains. More than 50 sedimentary samples from the Bauru Basin (southeast Brazil) were analyzed and show that only a small amount of grains are homogeneous (10%), questioning the validity of the rest of the grains for thermo-chronological evolution studies using zircon FTM dating.

U-Pb and Sm-Nd Evidence for Episodic Orogenic Gold Mineralization in the Kalgoorlie Gold Camp, Yilgarn Craton, Western Australia

2021 ◽  
Author(s):  
Jordan A. McDivitt ◽  
Steffen G. Hagemann ◽  
Anthony I.S. Kemp ◽  
Nicolas Thébaud ◽  
Christopher M. Fisher ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Western Australia ◽  
Late Stage ◽  
Gold Mineralization ◽  
Hydrothermal Systems ◽  
Orogenic Gold ◽  
Yilgarn Craton ◽  
Gold Telluride ◽  
Icp Ms ◽  
Metamorphic Fluids

Abstract Different genetic and timing models for gold mineralization in the Kalgoorlie gold camp (Yilgarn craton, Western Australia) suggest either broadly synchronous, late-stage mineralization related to metamorphic fluids at ca. 2640 Ma or a punctuated mineralization history from ca. 2675 to 2640 Ma with the involvement of early magmatic-hydrothermal systems (represented by the Fimiston, Hidden Secret, and Oroya gold-telluride lodes) and late metamorphic fluids (represented by the Mt. Charlotte gold stockwork veins). The results of U-Pb and Sm-Nd geochronological studies of zircon, apatite, and titanite from pre-ore dikes and syn-ore dikes constrain the absolute timing of mineralization and provide new evidence to this timing controversy. Emplacement ages constrained by U-Pb sensitive high-resolution ion microprobe (SHRIMP) zircon data are interpreted to be similar for both the pre-ore dikes (n = 10) and syn-ore dikes (n = 7) at ca. 2675 Ma. An inferred emplacement age of ca. 2675 Ma for the syn-ore dikes is supported by a Sm-Nd isochron age from apatite (laser ablation-inductively coupled plasma-mass spectrometry; LA-ICP-MS) of 2678 ± 15 Ma and by a U-Pb titanite age (LA-ICP-MS) of 2679 ± 6 Ma. The results of chemical abrasion-isotope dilution-thermal ionization mass spectrometry U-Pb zircon analysis from the pre- and syn-ore dikes are complicated by multistage Pb loss, reverse discordance, and potential inheritance. However, the data are compatible with the emplacement of Fimiston/Hidden Secret gold mineralization at ca. 2675 Ma and suggest a younger age for Oroya mineralization at ca. 2665 Ma. These results contrast with models for orogenic gold deposits that invoke broadly synchronous, late-stage mineralization related to metamorphic fluids at ca. 2640 Ma. The bulk of the Kalgoorlie gold camp’s estimated 2,300 t Au endowment was emplaced at ca. 2675 Ma as Fimiston/Hidden Secret Au mineralization. This early Au mineralization was deformed and overprinted twice by subordinate Au mineralization at ca. 2665 (Oroya mineralization) and ca. 2640 Ma (Mt. Charlotte mineralization). Gold mineralization in the Kalgoorlie gold camp was protracted in nature from ca. 2675 to 2640 Ma and reflects the interplay of early magmatic (Fimiston, Hidden Secret, Oroya) and late metamorphic (Mt. Charlotte) hydrothermal fluid systems in the formation of hybrid intrusion-related and metamorphic orebodies.

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