scholarly journals Crystal Size Distribution of amphibole and plagioclase from Zanbil adakitic dacites, Urmia- Iran: Evidence for magma mixing and textural coarsening

2015 ◽  
pp. 89-101 ◽  
Author(s):  
Monir Modjarrad
Keyword(s):  
Size Distribution ◽  
Crystal Size ◽  
Magma Mixing ◽  
Crystal Size Distribution ◽  
Textural Coarsening

scholarly journals Crystal size and shape distribution systematics of plagioclase and the determination of crystal residence times in the micromonzogabbros of Qisir Dagh, SE of Sabalan volcano (NW Iran)

2015 ◽  
Vol 66 (4) ◽  
pp. 257-268 ◽  
Author(s):  
Hamed Pourkhorsandi ◽  
Hassan Mirnejad ◽  
Davoud Raiesi ◽  
Jamshid Hassanzadeh
Keyword(s):  
Chemical Composition ◽  
Size Distribution ◽  
Crystal Size ◽  
Magma Mixing ◽  
Crystal Size Distribution ◽  
Distribution Data ◽  
Near Surface ◽  
Shape Distribution ◽  
Size And Shape ◽  
Sabalan Volcano

AbstractThe Qisir Dagh igneous complex occurs as a combination of volcanic and intrusive rocks to the south-east of the Sabalan volcano, north-western Iran. Micromonzogabbroic rocks in the region consist of plagioclase, alkaline feldspar and clinopyroxene as the major mineral phases and orthopyroxene, olivine, apatite and opaque minerals as the accessory minerals. Microgranular and microporphyritic textures are well developed in these rocks. Considering the importance of plagioclase in reconstructing magma cooling processes, the size and shape distribution and chemical composition of this mineral were investigated. Based on microscopic studies, it is shown that the 2-dimensional size average of plagioclase in the micromonzogabbros is 538 micrometers and its 3-dimensional shape varies between tabular to prolate. Crystal size distribution diagrams point to the presence of at least two populations of plagioclase, indicating the occurrence of magma mixing and/or fractional crystallization during magma cooling. The chemical composition of plagioclase shows a wide variation in abundances of Anorthite-Albite-Orthoclase (An=0.31–64.58, Ab=29.26–72.13, Or=0.9–66.97), suggesting a complex process during the crystal growth. This is also supported by the formation of antiperthite lamellae, which formed as the result of alkali feldspar exsolution in plagioclase. The calculated residence time of magma in Qisir Dagh, based on 3D crystal size distribution data, and using growth rate G=10−10mm/s, varies between 457 and 685 years, which indicates a shallow depth (near surface) magma crystallization and subvolcanic nature of the studied samples.

Magma chamber evolution of the Ardestan pluton, Central Iran: evidence from mineral chemistry, zircon composition and crystal size distribution

2019 ◽  
Vol 83 (6) ◽  
pp. 763-780 ◽  
Author(s):  
Shahrouz Babazadeh ◽  
Tanya Furman ◽  
John M. Cottle ◽  
Davood Raeisi ◽  
Ianna Lima
Keyword(s):  
Size Distribution ◽  
Crystal Size ◽  
Magma Mixing ◽  
Mineral Chemistry ◽  
Crystal Size Distribution ◽  
Plagioclase Feldspar ◽  
Magmatic Origin ◽  
Field Evidence ◽  
History Of ◽  
Chemical Conditions

AbstractThe Oligo–Miocene Ardestan quartz diorite to tonalite is part of widespread Cenozoic magmatism within the Urumieh–Dokhtar Magmatic Assemblage of Iran. The Ardestan pluton is composed mainly of varying proportions of plagioclase feldspar (normally zoned from bytownite to andesine), amphibole (magnesio-hornblende) and biotite. Biotite exhibits a range of Al values (~2–2.8 apfu) over very restricted Fe# ratios (0.42–0.56) which are characteristic of continental arc magmatic suites. High Ti2O contents of biotite (<6.1 wt.%) suggest a magmatic origin. Ti-in-biotite geothermometery gives a mean crystallisation temperature of 730 ± 56°C, slightly higher than calculated TZr.Ti°C (716 ± 50°C) and similar to the average TZr.sat°C (735 ± 26°C). These results are consistent with the low bulk-rock SiO2 contents, which provide minimum estimates of temperature and indicate zircon crystallised from a fractionated magma. Zircons from the Ardestan pluton have high (Sm/La)N (>10) ratios suggesting a magmatic origin. T–$f_{{\rm O}_{\rm 2}}$ calculations of oxygen fugacity between –13.6 to –16.9 indicate oxidising crystallisation conditions between the Ni–NiO (NNO) and Fe2O3–Fe3O4 (HM) buffers. Tight linear trends of log (XF/XOH), log (XCl/XOH) and log (XCl/XOH) vs. XMg represent a narrow range of $f_{{\rm H}_2O}$, fHF and fHCl, clearly indicating that physico-chemical conditions were essentially constant throughout the formation of magmatic biotite. The shape of crystal size distribution curves along with the medium Al and Mg contents in amphibole and biotite, respectively, are consistent with a history of magma mixing involving injections of basic magma into the evolving felsic chamber. Calculated residence time for Ardestan plagioclase crystals of ~630 years support field evidence that these plutons were emplaced at shallow depths.

scholarly journals Geochemistry and Texture of Clinopyroxene Phenocrysts from Paleoproterozoic Picrobasalts, Karelian Craton, Fennoscandian Shield: Records of Magma Mixing Processes

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 434 ◽  
Author(s):  
Sergei A. Svetov ◽  
Svetlana Y. Chazhengina ◽  
Alexandra V. Stepanova
Keyword(s):  
Size Distribution ◽  
Crystal Size ◽  
Magma Mixing ◽  
Fennoscandian Shield ◽  
Crystal Size Distribution ◽  
Distribution Analysis ◽  
Trace Element Data ◽  
Magmatic System ◽  
Karelian Craton ◽  
Mixing Processes

This paper presents an integrated major and trace element data and crystal size distribution analysis for zoned clinopyroxene phenocrysts hosted in variolitic and massive picrobasalts of the Suisaari Formation, Karelian Craton, Eastern Fennoscandian Shield. Clinopyroxenes in variolitic and massive lavas occur as unzoned, reverse, and normally zoned crystal. Oscillatory-zoned clinopyroxenes are only observed in variolitic lavas. The obtained data were examined in order to evaluate the contribution of magmatic processes such as magma mixing, contamination and fractional crystallization to the formation of various zoning patterns of clinopyroxene phenocrysts. Clinopyroxene phenocrysts in both variolitic and massive lavas originate from similar primary melts from a single magmatic source. The obtained data on composition and texture of clinopyroxene phenocrysts together with the crystal size distribution (CSD) analysis suggest that crystallization of the massive lavas mainly involves fractionation in a closed magmatic system, whereas the crystallization of the variolitic lavas is determined by processes in an open magmatic system. The results provide novel information on the evolution of Paleoproterozoic magmatic systems in the Karelian Craton.

scholarly journals Tunable Protein Crystal Size Distribution via Continuous Slug-Flow Crystallization with Spatially Varying Temperature

CrystEngComm ◽  
2021 ◽  
Author(s):  
Nicholas Mozdzierz ◽  
Moo Sun Hong ◽  
Yongkyu Lee ◽  
Moritz Benisch ◽  
Mo Jiang ◽  
...  
Keyword(s):  
Product Quality ◽  
Size Distribution ◽  
Slug Flow ◽  
Crystal Size ◽  
Quality Attributes ◽  
Crystal Size Distribution ◽  
Protein Crystal ◽  
Manufacturing Cost ◽  
Spatially Varying

Accompanied with the growth of the biopharmaceuticals market has been an interest in developing processes with increased control of product quality attributes at low manufacturing cost, with one of the...

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