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1.
V. V. Gulbin 《Ocean Science Journal》2005,40(1):45-54
The history of investigation of the family Velutinidae from 1776 to the present day is briefly described in the last part
of this review; the contemporary system of the family, consisting of 39 species and subspecies, belonging to 17 genera and
subgenera, and three subfamilies, is presented here. A biogeographic analysis of the fauna has been made, the history of origin
and development of the family, vertical distribution and relation to substrates have been described in this work. 相似文献
2.
Yu. L. Gulbin 《Geology of Ore Deposits》2016,58(7):559-567
The objective of this study is to provide insights into the REE and Y behavior during garnet porphyroblast formation in staurolite-bearing schists as a constituent of Late Paleoproterozoic metapelites of the Ladoga Complex. The MnNCKFMASH P–T pseudosection for a single sample and Grt–Bt thermometry indicate that the garnet core grew at 520°C and under 7.0–7.2 kbar in the Grt–Bt–Pl–Chl–Ms–Zo field, whereas the garnet rim was equilibrated at 590–600°C and under 3.5–4.0 kbar. The measured zoning profiles are strongly depleted in REE + Y in the garnet core containing high Mn and Ca concentrations. The intermediate zone of garnet is enriched in La, Ce, Pr, and Nd (inner LREE + Nd annulus), as well as in Dy, Er, Yb, Lu, and Y (outer HREE + Y + Dy annulus). According to pseudosection analysis, these peaks were probably produced owing to breakdown of epidote-group minerals (allanite, REE-rich epidote) at T < 535°C and P > 6.5 kbar. Towards the rim, the HREE + Y contents gradually decrease, whereas MREE (Sm, Eu, Gd) display an inverse trend. The rim also exhibits a negative Eu anomaly. The former tendency reflects an increase in temperature during garnet crystallization and partitioning of elements between garnet and monazite. It is thought that the latter is linked to oppositely directed change in garnet-monazite partition coefficients for HREE and MREE with increasing temperature. 相似文献
3.
Yu. L. Gulbin 《Geology of Ore Deposits》2011,53(7):543-557
Calibrations of the garnet-biotite geothermometer are considered with allowance for the effect of the nonideality of the coexisting
garnet and biotite upon K
D
. The calibrations based on the model of an asymmetric subregular Prp-Alm-Grs-Sps solid solution with W
i−j
Grt (after Ganguly et al. (1996) and Holdaway (2000) and taking into account the experimental data published by Perchuk et al.
(1983)) are the most accurate. The same may be said about the equations additionally taking into consideration the model of
the symmetric regular Phl-Ann-Ms-(Ti-Bt) solution with W
i−j
Bt after Holdaway et al., (1997), Kaneko and Miano (2004), and the data published by Ferry and Spear (1978) and Perchuk et al.
(1983). These equations well reproduce the temperature at which the Prp + Ann = Alm + Phl equilibrium is reached in experiments,
and they are the least sensitive to the variation of the Ca and Mn contents in garnet and AlVI and Ti in biotite. The uncertainty of the temperature interval is 30–46°C (2σ). 相似文献
4.
Yu. L. Gulbin 《Geology of Ore Deposits》2012,54(8):602-615
The possibility of using a garnet-biotite geothermometer to estimate the nucleation temperature of zoned crystals is considered. The data on the temperature evolution of mineral systems in the course of porphyroblast growth estimated with different methods are compared for a number of metamorphic provinces. The temperatures for garnet core and rim growth calculated by the program THERMOCALC are systematically overestimated compared to those derived using the garnet-biotite geothermometer (Kaneko and Miyano, 2004; Gulbin, 2011a, 2011b). The discrepancy reaches 40–70°C for the isopleth method and 60–90°C for the average PT method. 相似文献
5.
Yu. L. Gulbin 《Geology of Ore Deposits》2011,53(7):528-542
With the purpose to improve the garnet-biotite geothermometer, the published data on the interaction parameters have been
compared for the components of garnet and biotite solid solutions. On the basis of the reference metapelitic series, it has
been shown that the temperatures determined using various calibration equations for garnets enriched in Ca and Mn are systematically
over- or underestimated. The difference between the estimated and expected temperatures may be as great as many tens of degrees. 相似文献
6.
Yu. L. Gulbin 《Geology of Ore Deposits》2013,55(8):625-636
Results from the modeling of compositional zoning patterns in garnet porphyroblasts from the medium-grade metapelitic schist of northern Ladoga area are considered. The P-T pseudosections in the model KMnFMASH system were calculated for this purpose using THERMOCALC software (Powell et al., 1998). Particular emphasis is placed upon the effect of garnet growth kinetics on the model zoning profiles for Mn (Gulbin, 2013). They fit the observed profiles if intergranular diffusion-controlled growth is assumed for porphyroblasts. Additionally, a model of metamorphic fractional crystallization is used to characterize the oscillations in both the garnet core and rim. Starting from the assumption that a reservoir, where garnet grows, consists of chlorite, and that this mineral is intensely replaced with biotite and staurolite at the onset of crystallization, a partial release of Mn from the chlorite structure and the concentration of this component in intergranular space is inferred. In terms of the model under consideration, the coefficient of the Mn partition between garnet and reservoir temporarily increases at the early stage of garnet growth, giving rise to the enrichment of the intermediate zone of porphyroblasts in Mn. In addition to the modeling of garnet growth zoning, its subsequent diffusion modification is estimated on the basis of intracrystalline diffusion profile simulation. The reverse zoned, Mn-rich and Mg-poor garnet rims are related to retrograde growth of garnet at the late stage of porphyroblast formation. The data obtained are used to constrain metamorphic evolution and the P-T-t path of staurolite-bearing rocks in the northern domain of the studied area. 相似文献
7.
Knowledge of mineral aggregate morphologies is of importance to analyze characteristic differences in rock-forming features. For quantifying these differences, the fractal geometry of quartz aggregate cuts digitized from polish sections of different types of granites has been studied. As an approach to measure fractal dimension (D), a power-law dependence of square of aggregate cuts on their linear size has been used. The D values thus calculated mainly increase from 1.48–1.62 for amazonite granites to 1.63–1.70 for alaskite granites and 1.75–1.81 for standard granites. To account for the data of morphometry, the model of nucleation and growth as applied to silicate melt freezing has been considered. For comparison between the nature and model textures, the fractal properties of cluster cuts in the system of overlapping spheres randomly distributed with random radii have been investigated through computer simulation. It has been demonstrated that the distributions of quartz aggregates in granites may be simulated by homogeneous or heterogeneous Poisson models, and both order of crystallization and metamorphic recrystallization should be taken for explaining textural variability. The results of the simulation have enabled the granitic texture to be discussed with respect to the random configuration of the spatial percolation cluster. 相似文献
8.
Geology of Ore Deposits - The composition and interrelations of oxides (minerals of the spinel supergroup, corundum, ilmenite, rutile) and silicates (garnet, sillimanite, orthopyroxene, cordierite)... 相似文献
9.
Akbarpuran Haiyati S. A. Gulbin Yu. L. Sirotkin A. N. Gembitskaya I. M. 《Geology of Ore Deposits》2021,63(7):634-653
Geology of Ore Deposits - Abstract—Accessory REE- and Ti-bearing minerals have been investigated in rocks of the northern part of the West Ny Friesland anticlinorium, Svalbard Archipelago.... 相似文献
10.
Geology of Ore Deposits - Diverse geological complexes that form the crystalline basement of the East Antarctic Platform crop out in the Prince Charles Mountains. The Ruker Group is a member of the... 相似文献