Research output: Contribution to journal › Article › peer-review
Petrochemical Criteria of Staurolite Stability in Metapelites at Medium-Temperature Low- and Medium-Pressure Metamorphism. / Borisova, E. B.; Baltybaev, Sh K.
In: Petrology, Vol. 29, No. 4, 07.2021, p. 336-350.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Petrochemical Criteria of Staurolite Stability in Metapelites at Medium-Temperature Low- and Medium-Pressure Metamorphism
AU - Borisova, E. B.
AU - Baltybaev, Sh K.
N1 - Publisher Copyright: © 2021, Pleiades Publishing, Ltd.
PY - 2021/7
Y1 - 2021/7
N2 - Abstract: Staurolite stability in rocks of zonal metamorphic complexes and the subsequent decomposition of this mineral in the rocks at increasing temperature is a criterion for distinguishing the staurolite metamorphic zone. Along with other metamorphic zones, this zone reflects the temperature distribution configuration when the metamorphic zoning was formed. Staurolite-bearing mineral assemblages are formed in metapelites of appropriate chemical composition at metamorphic temperatures of ~500–650°C. The fact that staurolite is stable within a relatively narrow temperature range makes it possible to predict the presence or absence of this mineral in rocks if representative data on the composition of their protoliths are available. We propose a method for identifying potentially staurolite-bearing rocks using computational petrochemical modules, whose values are calibrated on natural rocks and modeled rock compositions that can occur in nature. Four petrochemical modules are proposed in the form of specified proportions of major chemical components in metamorphic rocks: Al2O3/SiO2, CaO/FM (where FM = FeOt + MgO), K2O/FM, and Na2O/FM. They can be used as criteria for estimating the possibility of staurolite crystallization in rocks when a suitable temperature (and pressure) is reached. These modules make it possible to select and more reliably specify the boundaries of the staurolite zone when, for example, maps of metamorphism are produced.
AB - Abstract: Staurolite stability in rocks of zonal metamorphic complexes and the subsequent decomposition of this mineral in the rocks at increasing temperature is a criterion for distinguishing the staurolite metamorphic zone. Along with other metamorphic zones, this zone reflects the temperature distribution configuration when the metamorphic zoning was formed. Staurolite-bearing mineral assemblages are formed in metapelites of appropriate chemical composition at metamorphic temperatures of ~500–650°C. The fact that staurolite is stable within a relatively narrow temperature range makes it possible to predict the presence or absence of this mineral in rocks if representative data on the composition of their protoliths are available. We propose a method for identifying potentially staurolite-bearing rocks using computational petrochemical modules, whose values are calibrated on natural rocks and modeled rock compositions that can occur in nature. Four petrochemical modules are proposed in the form of specified proportions of major chemical components in metamorphic rocks: Al2O3/SiO2, CaO/FM (where FM = FeOt + MgO), K2O/FM, and Na2O/FM. They can be used as criteria for estimating the possibility of staurolite crystallization in rocks when a suitable temperature (and pressure) is reached. These modules make it possible to select and more reliably specify the boundaries of the staurolite zone when, for example, maps of metamorphism are produced.
KW - metamorphic zoning
KW - metamorphism
KW - mineral assemblage
KW - petrochemical module
KW - staurolite
UR - http://www.scopus.com/inward/record.url?scp=85111289786&partnerID=8YFLogxK
U2 - 10.1134/S0869591121040020
DO - 10.1134/S0869591121040020
M3 - Article
AN - SCOPUS:85111289786
VL - 29
SP - 336
EP - 350
JO - Petrology
JF - Petrology
SN - 0869-5911
IS - 4
ER -
ID: 93113522