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PETROMODELER (Petrological Modeler): a Microsoft (R) Excel (R) spreadsheet program for modelling melting, mixing, crystallization and assimilation processes in magmatic systems
No full textPETROMODELER (Petrologic Modeler) is a Microsoft (R) Excel (R) spreadsheet program which numerically and graphically models magmatic processes including melting, crystallization, assimilation and mixing by using trace elements and isotopic ratios. Melting models include (a) batch, (b) dynamic (continuous) and (c) fractional melting for (1) instantaneous and (2) cumulate melts, (3) residual solid and (4) total residue. These models can also be used to treat modal and non-modal melting. Crystallization processes modelled in the program include: (1) perfect equilibrium and (2) perfect fractional crystallization (PEC and PFC), (3) equilibrium crystallization-imperfect fractional crystallization (EC-IFC), (4) zoned crystallization-imperfect fractional crystallization (ZC-IFC), and (5) combined assimilation and fractional crystallization (AFC). Mixing between two end-member compositions can also be modelled by the program. The main advantages of the program are that; (1) crystallization and mixing processes can be performed on a starting composition which may be chosen from; (a) any melting model result, or (b) any sample composition entered into the "samples" tables, (2) the results of any model can be exported as a graphic file (GIF) and as tables, (3) changes in any parameters are simultaneously updated onto all diagrams and tables. PETROMODELER also calculates other useful parameters, such as normative mineralogy, Mg#, Eu/Eu*, epsilon Sr and epsilon Nd, sigma(DM) (depleted mantle Nd model ages) of a given sample. Some classification diagrams for volcanic rocks are also included in the program. Conversion of element abundances on the basis of wt% and ppm can also be performed
A review of the Eocene to Quaternary volcanic evolution of the Western Anatolia: implications for potassic magma generation in collisional to post-collisional regions
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FC-AFC-FCA and mixing modeler: A Microsoft (R) Excel (c) spreadsheet program for modeling geochemical differentiation of magma by crystal fractionation, crustal assimilation and mixing
No full textSeveral petrological processes, such as (1) fractional crystallization (FC), (2) combined and decoupled fractional crystallization and assimilation (AFC and FCA), and (3) mixing processes, which modify the geochemical composition of the magma, are graphically programmed using Microsoft (R) Excel (c) spreadsheet on the basis of differentiation equations. The FC-AFC-FCA and mixing modeler is an interactive program that models the consequent theoretical vectors of FC, AFC, FCA, and mixing processes, which are frequently used in modern petrology. The program enables the user to export outputs of linear- or logarithmic-scaled bivariate diagrams and also rare earth elements (REE)- and multi-element spider diagrams of the modeling results. It also plots some classification diagrams as well as bivariate Harker variation diagrams. Because the program is interactive in nature, changes in any parameters are simultaneously updated onto all diagrams. (C) 2009 Elsevier Ltd. All rights reserved
Gürün Ve Kangal Havzalarındaki (Sivas) Erken Miyosen-Pliyosen Bazaltlarının Petrolojisi Ve Tektonik Önemi
No full textGeochemistry and petrology of the lower Miocene bimodal volcanic units in the Tuncbilek-Domanic basin, western Anatolia
No full textThe lower Miocene (similar to 22-19Ma) volcanic units in the NE-SW-trending Tuncbilek-Domanic basin, located in the northeastern-most part of the Neogene successions in western Anatolia, are composed of (1) high-K, calc-alkaline dacitic to rhyolitic volcanic rocks of the Oklukda volcanics; (2) calc-alkaline low-MgO (evolved) basalts; and (3) high-MgO mildly alkaline basalts of the Karakoy volcanics. Sr isotopic ratios of the volcanic units increase from high-MgO (similar to 0.7055-0.7057) to low-MgO basaltic rocks (similar to 0.7066-0.7072) and then to dacitic-rhyolitic rocks (0.7081-0.7086). Geochemical features of the volcanic rocks reveal that the calc-alkaline evolved basalts were formed by mixing of basic and acidic magmas.Geochemical studies in the last decade show that the Miocene mafic volcanic rocks in western Anatolia are mainly composed of high-MgO shoshonitic-ultrapotassic rocks (SHO-UK), of which mantle sources were variably, but also intensely metasomatized with crustally derived materials during collisional processes in the region. However, geochemical comparison of the high-MgO basalts of the Karakoy volcanics with the SHO-UK rocks in this region reveal that that the former has too low Sr-87/Sr-86((i)) and high Nd-143/Nd-144((i)) ratios, with lower LILE and LREE abundances, which are firstly described here. These features are interpreted to be derived from more slightly enriched lithospheric mantle sources than that of the SHO-UK. Accepting the SHO-UK rocks in the region were derived from mantle sources that had been metasomatized by northward subduction of crustal slices during Alpine collisional processes, it is proposed that the imbrication and direct subduction of crustal slices were not reached to, and were limited in the mantle domains beneath the basin. The dacites of the Oklukda volcanics might be formed either by high-degree melting of the same sources with the SHO-UK, or by melting of the lower crustal mafic sources as previously proposed, and then evolved into the rhyolites via fractional crystallization with limited crustal contribution
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Kızılcaören (Eskişehir) Yöresindeki Alkali Silikat ve Karbonatit Kayaçların Birlikteliği: Karbonatit Magmatizması Kökeninde Sıvı Karışmazlığı Süreçlerine Dair Çıkarımlar
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