TY - JOUR

T1 - Formation of High-Silica Leucocratic Granitoids on the Late Devonian Peraluminous Series of the Russian Altai: Mineralogical, Geochemical, and Isotope Reconstructions

AU - Kruk, Nikolay N.

AU - Gavryushkina, Olga A.

AU - Smirnov, Sergey Z.

AU - Kruk, Elena A.

AU - Rudnev, Sergey N.

AU - Semenova, Dina V.

N1 - The study was financially supported by the Russian Science Foundation (project 21-07-00175). Публикация для корректировки.

PY - 2023/4

Y1 - 2023/4

N2 - This paper presents data on the geological position, geochemical features, main mineral composition (micas, feldspars), and melt and fluid inclusions in quartz from Aba high-silica leucocratic granitoids in the western part of the Talitsa batholith, Russian Altai. According to these new geochemical data, the granitoids are classified as S-type, meaning they are formed via the partial melting of metasedimentary source rocks. Geological data and oxygen isotope composition analysis indicate that major-phase granitoid magma evolution took place at the level of intrusion formation, whereas the parent melt of late-phase leucogranite evolved in a deeper chamber. The geochemical features (HFSE and REE, and REE spectra) of the granitoids indicate significantly higher differentiation in the late leucocratic phase. The presence of coexisting syngenetic melt and fluid inclusions shows that leucogranite magma was already saturated with volatiles in the early crystallization stages. Based on the new data presented in this work, the Aba rock formation is associated with the volatile saturation of magmatic melts, the exsolution of a fluid phase, and magma degassing.

AB - This paper presents data on the geological position, geochemical features, main mineral composition (micas, feldspars), and melt and fluid inclusions in quartz from Aba high-silica leucocratic granitoids in the western part of the Talitsa batholith, Russian Altai. According to these new geochemical data, the granitoids are classified as S-type, meaning they are formed via the partial melting of metasedimentary source rocks. Geological data and oxygen isotope composition analysis indicate that major-phase granitoid magma evolution took place at the level of intrusion formation, whereas the parent melt of late-phase leucogranite evolved in a deeper chamber. The geochemical features (HFSE and REE, and REE spectra) of the granitoids indicate significantly higher differentiation in the late leucocratic phase. The presence of coexisting syngenetic melt and fluid inclusions shows that leucogranite magma was already saturated with volatiles in the early crystallization stages. Based on the new data presented in this work, the Aba rock formation is associated with the volatile saturation of magmatic melts, the exsolution of a fluid phase, and magma degassing.

KW - Altai

KW - geochemistry

KW - granitoids magmatism

KW - leucogranite

KW - mineralogy

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85156106924&origin=inward&txGid=251de8e133ff11eddbe152cbfccb1c11

UR - https://www.mendeley.com/catalogue/0a35b167-4caa-3f71-865a-f40a784b154e/

U2 - 10.3390/min13040496

DO - 10.3390/min13040496

M3 - Article

VL - 13

JO - Minerals

JF - Minerals

SN - 2075-163X

IS - 4

M1 - 496

ER -