Title of article :
P–V–T relation of MgO derived by simultaneous elastic wave velocity and in situ X-ray measurements: A new pressure scale for the mantle transition region
Author/Authors :
Kono، نويسنده , , Yoshio and Irifune، نويسنده , , Tetsuo and Higo، نويسنده , , Yuji and Inoue، نويسنده , , Toru and Barnhoorn، نويسنده , , Auke، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2010
Pages :
16
From page :
196
To page :
211
Abstract :
Simultaneous elastic wave velocity and in situ synchrotron X-ray measurements on polycrystalline MgO were carried out with a V/V0 between ∼0.9 and 1.0, which corresponds to the pressures up to 23.6 GPa in our P–V–T relation of MgO, and temperatures up to 1650 K using a multi-anvil apparatus. The experimentally observed adiabatic bulk modulus and unit-cell volume led to the first pressure-scale-independent P–V–T relation of MgO. We obtained a pressure derivative of the isothermal bulk modulus ( K ′ T 0 = 4.35 ( 10 ) ) and a volume dependent Grüneisen parameter (q0 = 1.5(5)), which reproduces the existing pressure-scale-independent data set (temperature dependence of elastic properties at ambient pressure and shock compression). Thus the present experimental and analytical procedure based on simultaneous elastic wave velocity and in situ X-ray diffraction measurements can give strong constraints on P–V–T equations of states (EoS) of minerals without any pressure scale. The present P–V–T EoS of MgO determined at pressure and temperature conditions comparable to the mantle transition region should be an important pressure scale to accurately determine the phase transition boundaries in this region. Application of the present pressure scale to the post-spinel transition boundary yields a transition pressure of 23.0 GPa at 1873 K, which is only marginally lower than that of the 660 km discontinuity.
Keywords :
MGO , Mantle transition region , equation of state , Elastic wave velocity
Journal title :
PHYSICS OF THE EARTH AND PLANETARY INTERIORS
Serial Year :
2010
Journal title :
PHYSICS OF THE EARTH AND PLANETARY INTERIORS
Record number :
2305945
Link To Document :
بازگشت