scholarly journals Caracterização Petrográfica e Geoquímica da Parte Leste do Granito Europa, Distrito Mineiro de Pitinga, AM

2007 ◽  
Vol 34 (1) ◽  
pp. 77 ◽  
Author(s):  
MAURÍCIO PRADO ◽  
JOSÉ TADEU MAXIMINO MIRRAS FERRON ◽  
EVANDRO FERNANDES DE LIMA ◽  
ARTUR CEZAR BASTOS NETO ◽  
VITOR PAULO PEREIRA ◽  
...  
Keyword(s):  
Fractional Crystallization ◽  
Genetic Relationship ◽  
Crystallization Process ◽  
Volcanic Rocks ◽  
Alkali Feldspar ◽  
Mineral Deposits ◽  
Geochemical Data ◽  
Principal Mechanism ◽  
Amazonian Region ◽  
Fractional Crystallization Process

The important mineral deposits of the Pitinga Mine, in the Amazonian region are related to A-type granites intruded in the Iricoumé Group. The Europa granite is one of these A-type rocks, intruded in the Iricoumé Group, which is represented by subaerial vulcanoclastic rocks (crystal-rich ignimbrites, thin massive tuffs and siltic tufaceous arenites) and minor hipabissal rhyolites. The volcanic rocks were probably generated in a caldera environment. The Europa granite is an alkali-feldspar peralkaline granite (hipersolvus) without genetic relationship with to the volcanic rocks of the Iricoumé Group, but it could have been generated during the resurgence stages. The petrographic and geochemical data attest that fractional crystallization process was the principal mechanism during the crystallization, which led to the generation of two different granitic facies. The Nb soil anomalies overprinted on the more differentiated facies are related to the astrophillite weathering.

Salt-forming regions of seawater type solution in the evaporation and fractional crystallization process

2014 ◽  
Vol 362 ◽  
pp. 281-287 ◽  
Author(s):  
Huan Zhou ◽  
Yanjuan Bao ◽  
Xiaoqin Bai ◽  
Ruoxin Ma ◽  
Lisha Huangfu ◽  
...  
Keyword(s):  
Fractional Crystallization ◽  
Crystallization Process ◽  
Type Solution ◽  
Fractional Crystallization Process

An early Proterozoic volcanic arc succession in southeastern Wyoming

1984 ◽  
Vol 21 (4) ◽  
pp. 415-427 ◽  
Author(s):  
Kent C. Condie ◽  
Craig A. Shadel
Keyword(s):  
Fractional Crystallization ◽  
Tectonic Setting ◽  
Volcanic Rocks ◽  
Geochemical Data ◽  
Alkaline Basalt ◽  
Calc Alkaline ◽  
Early Proterozoic ◽  
Enriched Mantle ◽  
Sierra Madre ◽  
Felsic Volcanic

The Green Mountain Formation of early Proterozoic age in the Sierra Madre Range of southeastern Wyoming comprises a bimodal mafic and felsic volcanic assemblage. The rocks, which are chiefly breccias, agglomerates, flows, and volcaniclastic sediments, represent both subaerial and submarine eruptions and in part were redeposited in fluvial and nearshore marine environments. Volcanic rocks are clearly calc-alkaline in character and share a large number of geochemical features in common with continental-margin arcs or evolved oceanic-arc systems.The low Mg numbers and Ni contents of the basalts require 30–40% olivine fractional crystallization, and the high contents of the most incompatible elements, high (La/Sm)N ratios, and low Zr/Nb ratios require an undepleted or enriched mantle source. Geochemical data are consistent with an origin for the felsic volcanics and associated Encampment River granodiorite by shallow fractional crystallization of calc-alkaline basalt in a tectonic setting similar to modern arc systems. The near absence of andesites may reflect the retention of andesitic magma in crustal reservoirs during fractional cyrstallization.

Proterozoic continental volcanism in the Belcher Islands: implications for the evolution of the Circum Ungava Fold Belt

1994 ◽  
Vol 31 (10) ◽  
pp. 1536-1549 ◽  
Author(s):  
F. Legault ◽  
D. Francis ◽  
A. Hynes ◽  
P. Budkewitsch
Keyword(s):  
Crystallization Process ◽  
Volcanic Rocks ◽  
Common Source ◽  
Chemical Compositions ◽  
Hudson Bay ◽  
Fold Belt ◽  
Segregation Process ◽  
Melt Segregation ◽  
Ree Patterns ◽  
Fractional Crystallization Process

The Belcher Islands of eastern Hudson Bay expose a continuous sequence of Early Proterozoic volcanics, and continental and shallow-marine sedimentary rocks. The volcanic rocks comprise two sequences of continental basalts: the older Eskimo Formation and the younger Flaherty Formation. The flows of both formations are composed of tholeiitic basalts (MgO < 9 wt.%) which, in each formation, are divided into two groups based on the concentrations of high field strength elements. Both groups of Eskimo flows have fractionated rare earth element (REE) patterns, with negative Nb anomalies. Relative to Eskimo flows, the Flaherty flows have flatter REE profiles and higher Nb contents. The chemical variations observed in the Eskimo flows are consistent with an assimilation – fractional crystallization process, involving a lower continental crust contaminant. The major and most trace element trends of the Flaherty flows are attributed to gabbroic crystal fractionation of two parental liquids, which are interpreted to represent varying degrees of partial melting of a common mantle source. An increase in La/Sm with increasing La, however, requires that the Flaherty flows evolved under open-system conditions, possibly in a replenished magma chamber or by selective contamination. The interbedding of low- and high-Zr flows in the upper portion of the Flaherty Formation combined with the possibility that their parental magmas originated from a common source require a complex melt segregation process in a partially molten ascending mantle.The chemical compositions of coeval basalts exposed along the eastern Hudson Bay coast and in the Cape Smith Fold Belt (western and eastern Povungnituk Group) indicate that they can be divided into two groups that are the chemical equivalents of the Eskimo and Flaherty Formations. Presently, the chemical stratigraphy of the Belcher Islands offers the most reliable means of correlating the isolated segments of Proterozoic supracrustal volcanics that rim the Superior Province of northern Quebec.

A geochemical study of two peraluminous granites from south-central Iberia: the Nisa-Albuquerque and Jalama batholiths

1999 ◽  
Vol 63 (1) ◽  
pp. 85-104 ◽  
Author(s):  
J. A. Ramirez ◽  
L. G. Menendez
Keyword(s):  
Fractional Crystallization ◽  
Magma Mixing ◽  
Geochemical Data ◽  
Magmatic Differentiation ◽  
Peraluminous Granite ◽  
South Central ◽  
Geochemical Study ◽  
Peraluminous Granites ◽  
Magma Pulses ◽  
Fractional Crystallization Process

AbstractIn this paper we present new petrological and geochemical data for two peraluminous granite batholiths (Nisa Alburquerque and Jalama batholiths) representative of the ‘Araya-type’ granites of the Central-Iberian Zone. Both granites are composite with several facies (monzogranites and leucogranites) that can be grouped into two main granite units: the external units and central units. Intrusive relationships and lack of geochemical coherence between the central and external units indicate that they are not comagmatic but represent different pulses. The central units of both batholiths are petrologically and geochemically different. On the other hand, external units show a lot of similarities and are the main object of this study. The main characteristics of the external granites can be interpreted in terms of an incomplete fractional crystallization process of early mineral phases (plg + Kf + bt) which probably took place at the level of emplacement. Other possible mechanisms of magmatic differentiation (magma mixing, restite unmixing, sequential melting) can be discarded based on field, petrography and geochemical data. We propose that the ‘Araya-type’ granites are formed by the intrusion of distinct magma pulses (central and external). Further evolution within each pulse can be due to incomplete fractional crystallization possibly taking place at the emplacement level.

Etude geochimique des elements en traces dans les series de roches volcaniques du rift d'Asal; identification et analyse des processus d'accretion

1980 ◽  
Vol S7-XXII (6) ◽  
pp. 851-861 ◽  
Author(s):  
J. L. Joron ◽  
M. Treuil ◽  
H. Jaffrezic ◽  
B. Villemant
Keyword(s):  
Partial Melting ◽  
Fractional Crystallization ◽  
Closed System ◽  
Mantle Source ◽  
Crystallization Process ◽  
Tectonic Activity ◽  
Dynamic Evolution ◽  
Mantle Material ◽  
Spreading Rates ◽  
Fractional Crystallization Process

Abstract Study of samples of the main volcanic units of the Afar rift, from margins to late axial series, have yielded the following conclusions: 1) the magmatic liquids are strongly differentiated by a fractional crystallization process in shallow chambers, the evolution of which is limited by injection of new primary liquids as shown in the latest axial series; 2) primary liquids are generated by melting of a homogeneous mantle source, a process whereby successive partial melting in a closed system is stopped by percolation of the generated liquid. The degrees of partial melting are closely related to spreading rates; 3) the magmatic processes involve a discontinuous dynamic evolution of spreading displayed by a pulsatory magmato-tectonic activity which is controlled by the speed of decompression of mantle material.

scholarly journals Effect of coolant temperature and cooling time on fractional crystallization of biodiesel and glycerol

2017 ◽  
Vol 13 (4) ◽  
pp. 676-679
Author(s):  
Shafirah Samsuri ◽  
Nurul Aini Amran ◽  
Loh Jia Zheng ◽  
Muhammad Muhaimin Mohd Bakri
Keyword(s):  
Methyl Ester ◽  
Fractional Crystallization ◽  
Crystallization Process ◽  
Current Method ◽  
Cooling Time ◽  
Coolant Temperature ◽  
Time Range ◽  
Separation And Purification ◽  
Wastewater Treatment Process ◽  
Fractional Crystallization Process

In the middle of the era of technology and fast-growing industry nowadays, biodiesel (methyl ester) has been identified as a sustainable fuel to replace petroleum. Hence, the separation and purification of the methyl ester after the trans-esterification process is essential since the purification of methyl ester is compulsory for the fuel industry in order to fulfill the strict global standard particulars for methyl ester. One of the current method used for separation and purification of methyl ester is called wet washing technology. However, this technology has its own drawbacks such as huge amount of water consumption as well as high cost for the wastewater treatment process. Due to these drawbacks, fractional crystallization process is proposed in order to save water and minimize the time consumed for the process of separation and purification of methyl ester. Fractional crystallization is a process that involved a solid-liquid separation where the process takes place in a crystallizer. In this process, methyl ester was separated from the glycerol based on their differences in term of melting point of the components. By observing the layer formation of the components, the effect of cooling time and coolant temperature on the performance of separation and purification of methyl ester by fractional crystallization process were studied. The purified methyl ester obtained was placed in a gas chromatographer in order to test the purity of methyl ester and to evaluate the efficiency of the process based on two parameters that has been investigated which are effective partition constant (K) and concentration efficiency (Eff). It was found that to achieve highest effectiveness of fractional crystallization system and highest concentration efficiency where K and Eff are 0.51 and 47.71%, respectively, the fractional crystallization must operate at coolant temperature range of -10 to -12ºC and cooling time range of 30 to 35 minutes.

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