Determination of Equation of stato of manthe minerals by in situ X-ray dillraction study.

用高温高压原位X射线衍射法测定了地幔矿物的P-V-T关系(状态方程)。测量是用DIA型立方压力机(MAX80)和来自国家高能物理研究所光子工厂的同步辐射强X射线进行的。确定物态方程的地幔矿物有橄榄石、改性尖晶石和尖晶石的镁硅酸镁，以及成分为95Mg2SiO_3-5Al_2O_3的镁铝榴石固溶体。测量的压力和温度范围如下：橄榄石，5-12 Gpa和25-1000ﾟC；变质尖晶石，12-17.5 Gpa和25-1100ﾟC；尖晶石，18-24 Gpa和25-800ﾟC；马来石榴石，6-23 Gpa和20-500ﾟC。

We have determined the P-V-T relation (equation of state) of mantle minerals by in-situ X-ray diffraction at high pressure and high temperature. The measurement was made by using DIA type cubic press (MAX80) and intense X-ray from the synchrotron radiation at Photon factory, National Institute of High Energy Physics. The mantle minerals whick we determine the equation of state are olivine, modified spinel and spinel of Mg2SiO4, and majorite garnet solid solution with a composition of 95Mg2SiO3-5Al2O3. The pressure and temperature range of the measurement were as follows ; olivine, 5-12 GPa and 25-1000ﾟC ; modified spinel, 12-17.5 GPa and 25-1100ﾟC ; spinel, 18-24 GPa and 25-800ﾟC ; majorite garnet, 6-23 GPa and 20-500ﾟC.Using these data determined here, we estimated the density profile along the geotherm in the upper mantle and the transition zone.