Study and Diagnostics of Convergent Rocks on the Example of Carbonated Fluid-Explosive Ultramaphic Dyke Complex (Middle Timan)

Fluid-explosive rocks of the dike complex are identified in the Middle Timan. The rocks have convergent properties due to a combination of explosive and metasomatic processes. The study of the petrographic features of the rocks revealed their explosive nature. Further study of the chemical composition of rock-forming minerals established the source of the mantle material and the paragenetic relationship with carbonatite magmatism. The fluid-explosive rocks of the dyke complex have a long-term multistage formation history. The fluids caused fenitization of the host strata and its disintegration. Solid-gas material of the mantle-crustal compound fills the cracks. At the last stage of formation of fluid-explosive rocks, the rare-metal, rare-earth, and sulfide mineralization took place.

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Finding of authigenous native gold in Novobobrovskoe rare-metal and rare-earth deposit (Chetlassky Kamen, Middle Timan)

Vestnik of Institute of Geology of Komi Science Center of Ural Branch RAS ◽

10.19110/2221-1381-2017-11-22-27 ◽

2017 ◽

Vol 11 ◽

pp. 22-27

Author(s):

Yu. V. Glukhov ◽

◽

O. V. Udotatina ◽

V. N. Filippov ◽

S. I. Isaenko ◽

...

Keyword(s):

Rare Earth ◽

Native Gold ◽

Rare Metal ◽

Middle Timan

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New Findings of Rare Minerals in Alkaline Rocks of Ukrainian Shield

Mineralogical Journal ◽

10.15407/mineraljournal.42.04.003 ◽

2020 ◽

Vol 42 (4) ◽

pp. 3-22

Author(s):

V.V. SHARYGIN ◽

S.G. KRYVDIK ◽

O.V. DUBYNA

Keyword(s):

Rare Earth ◽

Chemical Composition ◽

Ukrainian Shield ◽

Silicate Mineral ◽

Alkaline Rocks ◽

First Finding ◽

Azov Region ◽

New Findings ◽

Oxide Minerals

Over recent years, new rare minerals have been discovered in the alkaline rocks of the Ukrainian Shield. Agpaitic varieties of alkaline magmatic and metasomatic rocks turned out to be especially abundant in rare minerals. Numerous findings are related to alkaline metasomatites which are considered to be fenites and apofenite albitites of the Dmytrivka quarry. It is well known primarily by the presence of various accessory (Nb, REE, and Zr) minerals, as well as silicate and oxide minerals that are rare for Ukraine. The most common albite microcline fenites of this quarry are characterized by rare-earth mineralization, whereas the concentration of REE decreases in apofenite albitites and Zr and Nb increase. New rare minerals were also found in the essentially albite rock with astrophyllite, alkaline pyroxene and amphibole of the Malatersa massif and agpaitic phonolites of the Oktyabrsky massif. In the rocks of the mentioned massifs and occurrences of alkaline rocks the most interesting are the findings of the perraultite — jinshajiangite series. They were found in three points of the Azov area and include 1) perraultite and jinshajiangite in the alkaline metasomatites of the Dmytrivka quarry; 2) only perraultite in agpaitic phonolites of the Oktyabrsky massif (Kam’yana gully); 3) jinshajiangite in a veined albite rock among the gabbro of the Malatersa massif. Baotite and minerals of the hejtmanite — bafertisite series were also found in the metasomatites of the Dmytrivka quarry. The latter belong to intermediate varieties in terms of MnO (10-17 wt.%) and FeO (10-17 wt.%) which distinguishes them from Fe-rich bafertisite from other regions. A silicate mineral with high content of Na, Zr, Mn and elevated Ti and Nb is rarely observed as small inclusions in the kupletskite grains from alkaline metasomatite of the Dmytrivka quarry. According to the chemical composition it was previously diagnosed as janhaugite. Tainiolite was found in some occurrences of alkaline metasomatites in the Azov region. In addition small aggregates of the REE-enriched epidote were found in fenites of the Kaplany village, which is probably the first finding in Ukraine. Two new Zr minerals have been found in the aegirine syenites of the Korsun-Novomyrhorod pluton: elpidite and mineral with a high content of Y2O3 (13-14 wt.%) (Y-hagatalite ?).

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Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry

Journal of Glaciology ◽

10.1017/jog.2021.8 ◽

2021 ◽

pp. 1-27

Author(s):

H. Jay Zwally ◽

John W. Robbins ◽

Scott B. Luthcke ◽

Bryant D. Loomis ◽

Frédérique Rémy

Keyword(s):

Mass Balance ◽

Antarctic Peninsula ◽

East Antarctica ◽

Mantle Material ◽

West Antarctica ◽

Mantle Viscosity ◽

Grounding Line ◽

The Antarctic ◽

Total Gain

Abstract GRACE and ICESat Antarctic mass-balance differences are resolved utilizing their dependencies on corrections for changes in mass and volume of the same underlying mantle material forced by ice-loading changes. Modeled gravimetry corrections are 5.22 times altimetry corrections over East Antarctica (EA) and 4.51 times over West Antarctica (WA), with inferred mantle densities 4.75 and 4.11 g cm−3. Derived sensitivities (Sg, Sa) to bedrock motion enable calculation of motion (δB0) needed to equalize GRACE and ICESat mass changes during 2003–08. For EA, δB0 is −2.2 mm a−1 subsidence with mass matching at 150 Gt a−1, inland WA is −3.5 mm a−1 at 66 Gt a−1, and coastal WA is only −0.35 mm a−1 at −95 Gt a−1. WA subsidence is attributed to low mantle viscosity with faster responses to post-LGM deglaciation and to ice growth during Holocene grounding-line readvance. EA subsidence is attributed to Holocene dynamic thickening. With Antarctic Peninsula loss of −26 Gt a−1, the Antarctic total gain is 95 ± 25 Gt a−1 during 2003–08, compared to 144 ± 61 Gt a−1 from ERS1/2 during 1992–2001. Beginning in 2009, large increases in coastal WA dynamic losses overcame long-term EA and inland WA gains bringing Antarctica close to balance at −12 ± 64 Gt a−1 by 2012–16.

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Weathering mineral facies in altered granites: The importance of local small-scale equilibria

Mineralogical Magazine ◽

10.1180/minmag.1979.043.326.08 ◽

1979 ◽

Vol 43 (326) ◽

pp. 261-268 ◽

Cited By ~ 23

Author(s):

A. Meunier ◽

B. Velde

Keyword(s):

Chemical Composition ◽

Alkaline Earth ◽

Clay Mineralogy ◽

Small Scale ◽

Chemical Potentials ◽

Silica Activity ◽

Section Size ◽

Alkaline Earths ◽

Last Stage ◽

Rock Alteration

SummaryClassical clay mineralogy determinations and electron microprobe analyses of weathering minerals developed in altered two-mica granites indicate that the chemical forces that produce new minerals are often constrained to small volumes, frequently on the scale of a mineral grain or contact between two grains in the granite.Chemical potentials such as pH, alkali and alkaline earth and silica activity in the altering aqueous solutions provoke a destabilization of pre-existing minerals, which recrystallize locally to give a new multimineral product. The chemical composition of the new phases is largely governed by the relative concentrations of the elements present in the former minerals.Three mineral facies were observed in the weathered granites: initially a sericite-beidellitic type, then a beidellite-kaolinitic type, and finally a last stage kaolinite-oxide facies assemblage. The position of each facies is not restricted to a given depth in the profile but the relative proportions of each facies found in a thin-section size sample change towards the kaolinite-oxide facies.The global rock chemistry reflects the type facies predominant in each sample. The first two facies are roughly silica conservative while the kaolinite-oxide facies loses silica as well as alkali and alkaline earths.Geochemical and clay mineral studies of rock alteration should consider problems of mineral genesis at very localized sites.

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Monitoring the Chemical Composition of Air in Case of Interplanetary and Long-Term Space Flights: Problems, Approaches, and Solutions

Russian Journal of Physical Chemistry B ◽

10.1134/s1990793119040122 ◽

2019 ◽

Vol 13 (4) ◽

pp. 685-713

Author(s):

Sh. Sh. Nabiev ◽

G. Yu. Grigor’ev ◽

A. S. Lagutin ◽

L. A. Palkina ◽

A. A. Vasil’ev ◽

...

Keyword(s):

Chemical Composition ◽

Space Flights

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Oxygen embrittlement of Zircaloy-2 on long-term exposure to alkaline earth and rare earth oxides

Journal of Materials Science Letters ◽

10.1007/bf00730942 ◽

1982 ◽

Vol 1 (4) ◽

pp. 141-144 ◽

Cited By ~ 1

Author(s):

Rajiv Kohli

Keyword(s):

Rare Earth ◽

Alkaline Earth ◽

Rare Earth Oxides

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Modification of Non-Metallic Inclusions by Rare-Earth Elements in Microalloyed Steels

Archives of Foundry Engineering ◽

10.2478/v10266-012-0050-9 ◽

2012 ◽

Vol 12 (2) ◽

pp. 129-134 ◽

Cited By ~ 13

Author(s):

M. Opiela ◽

A. Grajcar

Keyword(s):

Rare Earth ◽

Chemical Composition ◽

Rare Earth Elements ◽

Mechanical Treatment ◽

Induction Furnace ◽

Microalloyed Steels ◽

Metallurgical Process ◽

Metallic Inclusions ◽

Mean Size ◽

Thermo Mechanical Treatment

Modification of Non-Metallic Inclusions by Rare-Earth Elements in Microalloyed Steels The modification of the chemical composition of non-metallic inclusions by rare-earth elements in the new-developed microalloyed steels was discussed in the paper. The investigated steels are assigned to production of forged elements by thermo-mechanical treatment. The steels were melted in a vaccum induction furnace and modification of non-metallic inclusions was carried out by the michmetal in the amount of 2.0 g per 1 kg of steel. It was found that using material charge of high purity and a realization of metallurgical process in vacuous conditions result in a low concentration of sulfur (0.004%), phosphorus (from 0.006 to 0.008%) and oxygen (6 ppm). The high metallurgical purity is confirmed by a small fraction of non-metallic inclusions averaging 0.075%. A large majority of non-metallic inclusions are fine, globular oxide-sulfide or sulfide particles with a mean size 17 μm2. The chemical composition and morphology of non-metallic inclusions was modified by Ce, La and Nd, what results a small deformability of non-metallic inclusions during hot-working.

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Lithogeochemical characteristics of metasandstones of the Chetlas series (Chetlassky Kamen, Middle Timan)

Vestnik of Geosciences ◽

10.19110/geov.2021.7.1 ◽

2021 ◽

pp. 3-12

Author(s):

N. Y. Nikulova ◽

◽

O. V. Udoratina ◽

I. V. Kozyreva

Keyword(s):

Inductively Coupled Plasma ◽

Volcanic Rocks ◽

Rare Metal ◽

Weathering Crust ◽

Terrigenous Material ◽

Inductively Coupled ◽

Coastal Marine ◽

Icp Ms ◽

Middle Timan ◽

Destruction Of Rocks

The lithological and geochemical features of the metasandstones of the Svetlinskaya and Vizingskaya formations of the Middle Late Riphean Chetlas series in the Middle Timan, which are a substrate of rare-metal-rare-earth mineralization in several ore occurrences of the Kosyus ore cluster, have been investigated. The interpretation of the results of traditional weight chemical and mass spectrometric inductively coupled plasma (ICP MS) analyses allowed us to identify differences in the material composition of metapesanics, mainly due to changes in the degree of sedimentation maturity of terrigenous material coming from the demolition areas. The composition of metasandstones in various ratios includes both weakly weathered products of destruction of volcanic rocks of intermediate/basic composition, and altered, including under conditions of the weathering crust, metaterrigenous formations. The accumulation of sediments took place in a shallow coastal-marine environment with changing hydrodynamics, which affected the rate of destruction of rocks in paleo-catchments.

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