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7483856 
Journal Article 
Mineral chemical constraints on the petrogenesis of mafic and intermediate volcanic rocks from the Erciyes and Hasandag volcanoes, Central Turkey 
Koprubasi, N; Guctekin, A; Celebi, D; Kirmaci, MZ 
2014 
Yes 
Chemie der Erde: Geochemistry
ISSN: 0009-2819
EISSN: 1611-5864 
74 
4 
585-600 
English 
CCC:000347502700006 
Hasandag and Erciyes stratovolcanoes, which produced both calc-alkaline and alkaline eruptive products, are the two important volcanic complexes in Central Anatolia. There are three geochemical evolution stages in the history of the Hasandag strato volcanic complex: (1) Kecikalesi tholeiitic, (2) Hasandag calc-alkaline and (3) Hasandag alkaline. Volcanologic and petrologic characteristics of the Hasandag and Erciyes calc-alkaline series show that water played an important role on the genesis of these rocks. These rocks are phenocryst-rich with vesicular texture, and contain hydrous mineral phases. The approximate pressure and temperature estimates obtained from the mineral chemistry studies of the Hasandag strato volcanic complex indicate crystallization temperature of 1100 degrees C with 2.5-3.4 kbar pressure interval for the first stage of Kecikalesi tholeiitic volcanism, and about 850 degrees C temperatures with 4.3-9.6 kbar pressure intervals for the second stage of Hasandag calc-alkaline volcanism. The geochemical evolution of Erciyes volcanic complex also exhibits three distinct evolutionary stages: (1) Kocdag alkaline, (2) Kocdag calc-alkaline and (3) Erciyes calc-alkaline. The temperature of Kocdag alkaline volcanism is 1097-1181 degrees C and in a range of 5.1-6.7 kbar pressure, for Kocdag calc-alkaline volcanism 850-1050 degrees C temperature to 2.0-6.6 kbar pressure interval, and for Erciyes calc-alkaline volcanism about 950 degrees C temperature, to 3.2-7.9 kbar pressure intervals were calculated. Polybaric origin of magma chambers for calc-alkaline and alkaline rocks and disequilibrium parameters observed in phenocrysts indicate that the rocks were affected by magma mixing processes in crustal magma chambers. The disequilibrium features of amphibole and plagioclase phenocrysts in these rocks point the latent heat in magma chambers and periodic recharging with mafic magma chambers and also show that magmas reequilibrate before the eruption. (C) 2013 Elsevier GmbH. All rights reserved. 
Physical Sciences - Other Topics; Stratovolcanoes, Magma evolution, Magma mixing, Hasandag-Erciyes,; Central Anatolia; calc-alkaline differentiation, ferric-ferrous ratio, mn-ti oxides,; central anatolia, oxygen fugacity, magma, plagioclase, origin,; amphibole, stratovolcano