Research output: Contribution to journal › Article › peer-review
Conditions of crystallization, composition, and sources of rare-metal magmas forming ongonites in the Kalba—Narym zone, Eastern Kazakhstan. / Sokolova, E. N.; Smirnov, S. Z.; Khromykh, S. V.
In: Petrology, Vol. 24, No. 2, 01.03.2016, p. 153-177.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Conditions of crystallization, composition, and sources of rare-metal magmas forming ongonites in the Kalba—Narym zone, Eastern Kazakhstan
AU - Sokolova, E. N.
AU - Smirnov, S. Z.
AU - Khromykh, S. V.
PY - 2016/3/1
Y1 - 2016/3/1
N2 - This paper presents a study of ongonites from the Chechek and Akhmirovo dike belts located within the Kalba—Narym batholith in Eastern Kazakhstan. The obtained conclusions are based on the investigations of melt and fluid inclusion in quartz phenocrysts, supplemented by mineralogical and geochemical data. It was established that the dike rocks were formed by crystallization of volatile-rich rare-metal melts in the presence of an aqueous fluid phase with subordinate amounts of carbon dioxide and methane. The ongonites crystallized from three geochemically different melts. Porphyritic phenocrysts in the ongonites of the Chechek and Akhmirovo dike belts crystallized at close temperatures 560–605°C and pressure of 3.6–5.3 kbar. Ongonite magmas that formed the Chechek and Akhmirovo dike belts had a high ore potential. However, degassing dynamics was not favorable for the development of metasomatism and formation of hydrothermal mineralization at the level of dike emplacement. The area of the rare-metal magmatism represented by ongonite dikes and rare-metal granite pegmatites has been distinguished in the northern part of the Kalba—Narym zone. The formation of rare-metal magmas was related to the differentiation in large granitoid chambers under the effect of juvenile fluids derived from the Tarim mantle plume.
AB - This paper presents a study of ongonites from the Chechek and Akhmirovo dike belts located within the Kalba—Narym batholith in Eastern Kazakhstan. The obtained conclusions are based on the investigations of melt and fluid inclusion in quartz phenocrysts, supplemented by mineralogical and geochemical data. It was established that the dike rocks were formed by crystallization of volatile-rich rare-metal melts in the presence of an aqueous fluid phase with subordinate amounts of carbon dioxide and methane. The ongonites crystallized from three geochemically different melts. Porphyritic phenocrysts in the ongonites of the Chechek and Akhmirovo dike belts crystallized at close temperatures 560–605°C and pressure of 3.6–5.3 kbar. Ongonite magmas that formed the Chechek and Akhmirovo dike belts had a high ore potential. However, degassing dynamics was not favorable for the development of metasomatism and formation of hydrothermal mineralization at the level of dike emplacement. The area of the rare-metal magmatism represented by ongonite dikes and rare-metal granite pegmatites has been distinguished in the northern part of the Kalba—Narym zone. The formation of rare-metal magmas was related to the differentiation in large granitoid chambers under the effect of juvenile fluids derived from the Tarim mantle plume.
UR - http://www.scopus.com/inward/record.url?scp=84963773027&partnerID=8YFLogxK
U2 - 10.1134/S0869591116020065
DO - 10.1134/S0869591116020065
M3 - Article
AN - SCOPUS:84963773027
VL - 24
SP - 153
EP - 177
JO - Petrology
JF - Petrology
SN - 0869-5911
IS - 2
ER -
ID: 25762520