scholarly journals Geochemistry of garnet megacrysts from the Mir kimberlite pipe (Yakutia) and the nature of prothokimberlite melt

2019 ◽  
Vol 486 (5) ◽  
pp. 583-587
Author(s):  
A. M. Agashev
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Negative Correlation ◽  
Kimberlite Pipe ◽  
Major And Trace Elements ◽  
Major Elements ◽  
Incompatible Elements ◽  
Composition Study ◽  
Melt Composition

The paper presents the results of major and trace elements composition study of garnet megacrysts from Mir kimberlite pipe. On the major elements composition those garnets classified as low Cr and high Ti pyropes. Concentrations of TiO2 show a negative correlation with MgO и Cr2O3 contents in megacrysts composition. Fractional crystallization modeling indicates that the most appropriate melt to reproduce the garnet trace elements signatures is the melt of picritic composition. Composition of garnets crystallized from kimberlite melt do not correspond to observed natural garnets composition. Kimberlites contain less of Ti, Zr, Y and heavy REE (rare earth elements) but more of very incompatible elements such as light REE, Th, U, Nb, Ba then the model melt composition that necessary for garnet crystallization.

scholarly journals The distribution of the trace element contents in lignite and ash from Drama lignite deposit, using multivariate statistical analysis

2001 ◽  
Vol 34 (3) ◽  
pp. 1255
Author(s):  
S. PANILAS ◽  
G. HATZIYANNIS
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Statistical Analysis ◽  
Rare Earth Elements ◽  
Multivariate Statistical Analysis ◽  
Major And Trace Elements ◽  
Major Elements ◽  
Geochemical Data ◽  
Multivariate Statistical ◽  
Inorganic Matter

Multivariate statistical analysis was used on existing geochemical data of the Drama lignite deposit, eastern Macedonia, Greece. Factor analysis with varimax rotation technique was applied to study the distribution of major, trace and rare earth elements in the lignite and 850°C lignitic ash, to find a small set of factors that could explain most of the geochemical variability. The study showed that major elements AI, Na, Κ, contained in the lignite samples, presented high correlation with most of the trace and rare earth elements. In 850°C lignitic ashes major and trace elements present different redistribution. Only Al remained correlated with the trace elements Co, Cr, Rb, Ta, Th, Ti, Sc and rare earths related with inorganic matter in the lignite beds. Trace elements Fe, Mo, U, V, W, and Lu were associated with organic matter of lignite and had also been affected by the depositional environment.

Geochemistry of the Île Cadieux monticellite alnöite, Quebec, Canada

1991 ◽  
Vol 28 (7) ◽  
pp. 1050-1057 ◽  
Author(s):  
Luc Harnois ◽  
Raymond Mineau
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Mineral Chemistry ◽  
Major And Trace Elements ◽  
Major Elements ◽  
Chemical Compositions ◽  
Nickel Sulphide ◽  
Physicochemical Conditions ◽  
Iron Nickel

The Île Cadieux alnöite, a small Cretaceous intrusion, is a member of the Monteregian Hills Petrographic Province. Mineral chemistry was determined for olivine, spinel, clinopyroxene, melilite, and a potassium–iron–nickel sulphide akin to djerfisherite. Whole rocks were analysed for major elements and 24 trace elements (including rare-earth elements). The Île Cadieux alnöitic rocks have greater MgO/Al2O3 ratios than most alnöites but are otherwise similar to typical alnöites with respect to major and trace elements. Comparison of spinel and whole-rock chemical compositions from the Île Cadieux and Île Bizard (located 15 km to the northeast) alnöitic intrusions suggests that these magmas were generated under different physicochemical conditions of melting, or alternatively that they are fractions of a single magma which crystallized under different conditions.

scholarly journals Identifying Correlation of Coal Seams in the Tien Hai Area, Northern Vietnam by Using Multivariate Statistic Methods

2021 ◽  
Vol 1 (2) ◽  
Author(s):  
The Hung KHUONG ◽  
Phuong NGUYEN ◽  
Thi Cuc NGUYEN ◽  
Nhu Sang PHAM ◽  
Danh Tuyen NGUYEN
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Coal Seam ◽  
Rare Earth Elements ◽  
Major And Trace Elements ◽  
Coal Seams ◽  
Multivariate Statistic ◽  
Northern Vietnam ◽  
Coal Deposits ◽  
Indicator Elements

In northern Vietnam, the Tien Hai area is considered a high potential area of coal deposits. Twohundred fifty-six geochemical coal samples of 13 cores in the Tien Hai area investigate coal seams andcoal deposits to identify the correlation of coal seams. According to the statistical method and clusteranalysis of geochemical samples, the results indicate that the Mg, V, As, Ca, Zn, Cr, Co, K, Na, Sr, Fe,Ge, Re, U, Mo, Th, and Ga elements are good indicator elements of the major and trace elements in coal.Most of them comply with the normal or lognormal distribution rules. Besides, the Yb, Sc, Ho, Er, Tm,Lu, Y, Tb, Pr, Dy, and Sm elements are also good indicator elements for rare earth elements in the region.Therefore, the selected elements are used to identify the correlation of the coal seams in the Tien Hai area.Based on the similarity degree between studied objects, the results of grouping boreholes in coal seamsshow that the correlation of coal seam TV2-11 is suitable and acceptable, the coal seams TV3-6a, TV3-6b, and TV3-6c can be grouped into the coal seam TV3-6. These results present that the models can helpstudy geochemical coal samples and identify the correlation of the coal seams in the Tien Hai area.Additionally, the statistical analysis shows a remarkable degree to determine the correlation of the coalseams. Geochemical coal data can help to evaluate the indicator elements of the major, trace elements,and rare earth elements in coal seams and coal rashing of adjoining and pillar rocks in the Tien Hai area,northern Vietnam.

The Fate of Rare Earth Elements in Post-Fire Soils in the Pocono Mountains, Pennsylvania (USA)

2021 ◽  
Author(s):  
Gregory Pope ◽  
Jennifer Callanan ◽  
Jason Darley ◽  
Michael Flood ◽  
Jeffrey Wear ◽  
...  
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Forest Fires ◽  
Soil Profile ◽  
Major Elements ◽  
Wood Ash ◽  
Parent Material ◽  
Biomass Ash ◽  
Pocono Mountains

<p>The wood ash contribution to soils represents a unique and important part of soil organic carbon following fires.  Wood ash imparts chemical and physical changes to the soil, evident in elements other than carbon.  Our case studies are from recent wildfires and experimental burns in mixed hardwood forests in the Pocono Mountains of Pennsylvania, USA.  In these studies, we identified increases in most of the major elements and some minor elements in soils following forest fires, analyzed with ICP-MS. Elements such as Mn, Mg, Na, Ca, Na, K, Cu, and Ba, derive from an infusion of biomass ash, with variable contribution depending on, for instance, tree species. In the case of Ba and Cu, their presence is distinctly different from any mineral parent material contribution to the soil, and therefore unique signatures of fire contribution. Signature post-fire elements persist in some cases over one year following the fire, and are found in both topsoil horizons and into illuvial soil horizons.</p><p>In the course of these investigations, we also found a curious depletion of all rare earth elements (REEs) and certain trace elements from the soil following forest fires, and in adjacent stream and wetland sediments. The post-fire difference in REE concentration was statistically significant (p < 0.10, N=51) in all but Eu and U, with light REEs La, Ce and Pr showing the most significant decreases. Among other trace elements, Sc (which behaves similarly to REEs), V, Cr, Ga, and Rb also exhibited statistically significant decreases (though other elements Cu and Sr increase along with the ash input). The reasons for the depletions are unclear. Other authors report that REE dynamics in soils are poorly understood, but may be associated with phosphates, carbonates, and silicates in the soil. These are relatively enriched via post-fire biomass ash, yet the associated REEs are missing. It is unlikely that the elements would have preferentially translocated through and below the soil profile. Erosion is ruled out, otherwise the ash-associated major and trace elements would also be depleted. Two possible causes for post-fire REE loss are 1) volatilization from the soil during the fire, and 2) rapid uptake by post-fire succession plants, notably ferns, which are known to bioaccumulate REEs. Further research is warranted, following the ongoing post-fire vegetation recovery, and the dynamics of REEs within the soil profile.       </p>

Levels of major and trace elements, including rare earth elements, and 238U in Croatian tap waters

2014 ◽  
Vol 22 (9) ◽  
pp. 6789-6799 ◽  
Author(s):  
Željka Fiket ◽  
Martina Rožmarić ◽  
Matea Krmpotić ◽  
Ljudmila Benedik
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Major And Trace Elements

scholarly journals Partition coefficients of trace elements between carbonates and melt and suprasolidus phase relation of Ca-Mg-carbonates at 6 GPa

2020 ◽  
Vol 105 (6) ◽  
pp. 922-931 ◽  
Author(s):  
Melanie J. Sieber ◽  
Franziska Wilke ◽  
Monika Koch-Müller
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Partial Melting ◽  
Partition Coefficients ◽  
Divalent Cations ◽  
Major And Trace Elements ◽  
Element Distribution ◽  
Phase Relations ◽  
Trace Element Distribution

Abstract The presence of Ca-Mg-carbonates affects the melting and phase relations of peridotites and eclogites in the mantle, and (partial) melting of carbonates liberates carbon from the mantle to shallower depths. The onset and composition of incipient melting of carbonated peridotites and carbonated eclogites are influenced by the pure CaCO3-MgCO3-system making the understanding of the phase relations of Ca-Mg-carbonates fundamental in assessing carbon fluxes in the mantle. By performing high-pressure and high-temperature experiments, this study clarifies the suprasolidus phase relations of the nominally anhydrous CaCO3-MgCO3-system at 6 GPa showing that Ca-Mg-carbonates will (partially) melt for temperatures above ~1300 °C. A comparison with data from thermodynamic modeling confirms the experimental results. Furthermore, partition coefficients for Li, Na, K, Sr, Ba, Nb, Y, and rare earth elements between calcite and dolomitic melt, Ca-magnesite and dolomitic melt, and magnesite and dolomitic melt are established. Experiments were performed at 6 GPa and between 1350 to 1600 °C utilizing a rotating multi-anvil press. Rotation of the multi-anvil press is indispensable to establish equilibrium between solids and carbonate liquid. Major and trace elements were quantified with EPMA and LA-ICP-MS, respectively. The melting temperature and phase relations of Ca-Mg-carbonates depend on the Mg/Ca-ratio. For instance, Ca-rich carbonates with a molar Mg/(Mg+Ca)-ratio (XMg) of 0.2 will transform into a dolomitic melt (XMg = 0.33–0.31) and calcite crystals (XMg = 0.19–0.14) at 1350–1440 °C. Partial melting of Mg-rich carbonates (XMg = 0.85) will produce a dolomitic melt (XMg = 0.5–0.8) and Ca-bearing magnesite (XMg = 0.89–0.96) at 1400–1600 °C. Trace element distribution into calcite and magnesite seems to follow lattice constraints for divalent cations. For instance, the compatibility of calcite (XMg = 0.14–0.19) for Sr and Ba decreases as the cation radii increases. Ca-Mg-carbonates are incompatible for rare earth elements (REEs), whereby the distribution between carbonates and dolomitic melt depends on the Mg/Ca ratio and temperature. For instance, at 1600 °C, partition coefficients between magnesite (XMg = 0.96) and dolomitic melt (XMg = 0.8) vary by two orders of magnitudes from 0.001 to 0.1 for light-REEs to heavy-REEs. In contrast, partition coefficients of REEs (and Sr, Ba, Nb, and Y) between magnesite (XMg = 0.89) and dolomitic melt (XMg = 0.5) are more uniform scattering marginal between ~0.1–0.2 at 1400 °C.

scholarly journals Characteristics of Trace Elements in Volcanic ash of Kelud Eruption in East Java, Indonesia

2018 ◽  
Vol 18 (3) ◽  
pp. 457 ◽  
Author(s):  
Diah Dwiana Lestiani ◽  
Revi Apryani ◽  
Linda Lestari ◽  
Muhayatun Santoso ◽  
Eko Prabowo Hadisantoso ◽  
...  
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Volcanic Ash ◽  
Reference Data ◽  
Major Elements ◽  
X Ray ◽  
Wide Range ◽  
Volcanic Ashes ◽  
Good Agreement

The eruption of Mount Kelud that occurred on February 13, 2014, ejected a huge plume of ash and sand exceeding 26 km into the air which moved west over the island. The elements content in volcanic ash is important information for further study such as the possibility to utilize the ash. In this study, the volcanic ashes collected from four affected areas in Java were analyzed using neutron activation analysis (NAA) with HPGe detector and X-ray fluorescence. Method validation was applied using the standard reference material SRM NIST 2711a Montana Soil with recovery and accuracy in a good agreement for all elements. The analysis results of volcanic ashes showed a wide range of elements, major elements Al, Ca, Fe, K, Mg, Mn, Na, Si and Ti, trace elements As, Cd, Cu, Co, Cr, V, Zn, Hf, Th and U, and rare earth elements were identified. The results showed heavy metals As, Cd, Cu, Co, Cr, and Pb were ranged 3.23–4.42, 17.63–24.09, 49.26–77.10, 10.86–16.03, 11.19–17.79 and 31.4–42.7 mg/kg, respectively, while rare earth elements such as Ce, Eu, La, and Sm were 9.84–18.43, 0.73–1.02, 2.25–5.66 and 1.34–2.63 mg/kg respectively. Comparison with other volcanic ashes from Indonesia such as Merapi and Sinabung and world volcanic ashes were applied. The results of the characteristic of elements in Kelud volcanic ash would be valuable information as reference data for their potential utilization.

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