Viscosity of hydrous kimberlite and basaltic melts at high pressures. / Persikov, E. S.; Bukhtiyarov, P. G.; Sokol, A. G.
In: Russian Geology and Geophysics, Vol. 58, No. 9, 01.09.2017, p. 1093-1100.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Viscosity of hydrous kimberlite and basaltic melts at high pressures
AU - Persikov, E. S.
AU - Bukhtiyarov, P. G.
AU - Sokol, A. G.
N1 - Publisher Copyright: © 2017
PY - 2017/9/1
Y1 - 2017/9/1
N2 - New experimental data on the temperature and pressure dependences of the viscosity of synthetic hydrous kimberlite melts (82 wt.% silicate + 18 wt.% carbonate; degree of depolymerization: 100NBO/T = 313 for anhydrous melts and 100NBO/T = 247 for melts with 3 wt.% H2O) were obtained at a water pressure of 100 MPa and at lithostatic pressures of 5.5 and 7.5 GPa in the temperature range 1300-1950 °C. The temperature dependence of the viscosity of these melts follows the exponential Arrhenius-Frenkel-Eyring equation in the investigated range of temperatures and pressures. The activation energies of viscous flow for hydrous kimberlite melts were first shown to increase linearly with increasing pressure. Under isothermal conditions (T = 1800 °C), the viscosity of hydrous kimberlite melts increases exponentially by about an order of magnitude as the pressure increases from 100 MPa to 7.5 GPa. The new experimental data on the viscosity of hydrous kimberlite melts (error ± 30 rel.%) are compared with forecast viscosity data for anhydrous kimberlite and basaltic melts (100NBO/T = 51.5) and for hydrous basaltic melts (100NBO/T = 80). It is shown that at comparable temperatures, the viscosity of hydrous kimberlite melts at a moderate pressure (100 MPa) is about an order of magnitude lower than the viscosity of hydrous basaltic melts, whereas at a high pressure (7.5 GPa) it is more than twice higher. It is first established that water dissolution in kimberlite melts does not affect seriously their viscosity (within the measurement error) at both moderate (100 MPa) and high (7.5 GPa) pressures, whereas the viscosity of basaltic melts considerably decreases with water dissolution at moderate pressures (100 MPa) and remains unchanged at high pressures (P > 3.5 GPa).
AB - New experimental data on the temperature and pressure dependences of the viscosity of synthetic hydrous kimberlite melts (82 wt.% silicate + 18 wt.% carbonate; degree of depolymerization: 100NBO/T = 313 for anhydrous melts and 100NBO/T = 247 for melts with 3 wt.% H2O) were obtained at a water pressure of 100 MPa and at lithostatic pressures of 5.5 and 7.5 GPa in the temperature range 1300-1950 °C. The temperature dependence of the viscosity of these melts follows the exponential Arrhenius-Frenkel-Eyring equation in the investigated range of temperatures and pressures. The activation energies of viscous flow for hydrous kimberlite melts were first shown to increase linearly with increasing pressure. Under isothermal conditions (T = 1800 °C), the viscosity of hydrous kimberlite melts increases exponentially by about an order of magnitude as the pressure increases from 100 MPa to 7.5 GPa. The new experimental data on the viscosity of hydrous kimberlite melts (error ± 30 rel.%) are compared with forecast viscosity data for anhydrous kimberlite and basaltic melts (100NBO/T = 51.5) and for hydrous basaltic melts (100NBO/T = 80). It is shown that at comparable temperatures, the viscosity of hydrous kimberlite melts at a moderate pressure (100 MPa) is about an order of magnitude lower than the viscosity of hydrous basaltic melts, whereas at a high pressure (7.5 GPa) it is more than twice higher. It is first established that water dissolution in kimberlite melts does not affect seriously their viscosity (within the measurement error) at both moderate (100 MPa) and high (7.5 GPa) pressures, whereas the viscosity of basaltic melts considerably decreases with water dissolution at moderate pressures (100 MPa) and remains unchanged at high pressures (P > 3.5 GPa).
KW - basalt
KW - Earth's crust
KW - kimberlite
KW - mantle
KW - melt
KW - model
KW - pressure
KW - temperature
KW - viscosity
KW - water
KW - SYSTEM
KW - LIQUID
KW - MAGMATIC MELTS
KW - EARTHS CRUST
KW - PARAMETERS
KW - SILICATE MELTS
KW - ORIGIN
KW - GPA
KW - CONSTRAINTS
KW - WATER
UR - http://www.scopus.com/inward/record.url?scp=85031756439&partnerID=8YFLogxK
U2 - 10.1016/j.rgg.2017.08.005
DO - 10.1016/j.rgg.2017.08.005
M3 - Article
AN - SCOPUS:85031756439
VL - 58
SP - 1093
EP - 1100
JO - Russian Geology and Geophysics
JF - Russian Geology and Geophysics
SN - 1068-7971
IS - 9
ER -
ID: 9890469