Research output: Contribution to journal › Article › peer-review
Thermal equation of state of NaMg0.5Si2.5O6 and new data on the compressibility of clinopyroxenes. / Dymshits, A. M.; Sharygin, I. S.; Podborodnikov, I. V. et al.
In: Doklady Earth Sciences, Vol. 461, No. 1, 01.03.2015, p. 273-276.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Thermal equation of state of NaMg0.5Si2.5O6 and new data on the compressibility of clinopyroxenes
AU - Dymshits, A. M.
AU - Sharygin, I. S.
AU - Podborodnikov, I. V.
AU - Litasov, K. D.
AU - Shatskiy, A. F.
AU - Otani, E.
AU - Pushcharovskii, D. Yu
PY - 2015/3/1
Y1 - 2015/3/1
N2 - The results of studies of the P-V-T equations of state (EOS) of Na-pyroxene using the multi-anvil technique and synchrotron radiation at pressures up to 15.3 GPa and temperatures up to 1673 K are presented. By fitting the Birch-Murnaghan EOS, the following parameters were determined: V0 = 407.2 (5) Å3, the space group P2/n, KT0 = 103 (2) GPa, KT0 = 6.2 (7), ∂KT/∂T = −0.018 (7), α = 3.38(13) + 0.65(62)T. Thus, despite the small volume of the cell, Na-pyroxene has a sufficiently high bulk modulus. This can be caused by the appearance of antipathetic bonds in Na-polyhedron, Si-tetrahedra rotation, and the ordering of Mg and Si cations in the M1 position. Thus, it is substantiated that the phase transformations in the minerals accompanied by the presence of Si in octahedral coordination are characterized by a significant change in the physical characteristics, such as density (ρ) and bulk modulus (KT). Such transformations occurring in the minerals and deep Earth can lead to significant jumps in the seismic wave velocities. Therefore, the presence of phases with silicon in sixfold coordination, such as Na-Ca majoritic garnet is of fundamental importance for understanding the Earth’s upper mantle.
AB - The results of studies of the P-V-T equations of state (EOS) of Na-pyroxene using the multi-anvil technique and synchrotron radiation at pressures up to 15.3 GPa and temperatures up to 1673 K are presented. By fitting the Birch-Murnaghan EOS, the following parameters were determined: V0 = 407.2 (5) Å3, the space group P2/n, KT0 = 103 (2) GPa, KT0 = 6.2 (7), ∂KT/∂T = −0.018 (7), α = 3.38(13) + 0.65(62)T. Thus, despite the small volume of the cell, Na-pyroxene has a sufficiently high bulk modulus. This can be caused by the appearance of antipathetic bonds in Na-polyhedron, Si-tetrahedra rotation, and the ordering of Mg and Si cations in the M1 position. Thus, it is substantiated that the phase transformations in the minerals accompanied by the presence of Si in octahedral coordination are characterized by a significant change in the physical characteristics, such as density (ρ) and bulk modulus (KT). Such transformations occurring in the minerals and deep Earth can lead to significant jumps in the seismic wave velocities. Therefore, the presence of phases with silicon in sixfold coordination, such as Na-Ca majoritic garnet is of fundamental importance for understanding the Earth’s upper mantle.
UR - http://www.scopus.com/inward/record.url?scp=84928315940&partnerID=8YFLogxK
U2 - 10.1134/S1028334X15030113
DO - 10.1134/S1028334X15030113
M3 - Article
AN - SCOPUS:84928315940
VL - 461
SP - 273
EP - 276
JO - Doklady Earth Sciences
JF - Doklady Earth Sciences
SN - 1028-334X
IS - 1
ER -
ID: 25793431