Generation of ultra high pressure by the diamond-anvil cell and estimation of temperature of the Earth's core

我们对美国地球物理实验室毛博士等人的金刚石压腔进行了改进，研制了一种新型的金刚石压腔，它具有更稳定的活塞，适用于3000K以下的高温高压实验。使用这种金刚石对顶砧单元，我们得到了以下实验结果：高压熔融实验的软锰矿组合物进行。结果表明，其熔融曲线与MORB相似，支持外核温度超过4000 K的观点。我们发现更多的铁被分配到富镁钙钛矿在下地幔比早期的估计。这表明，地球的下地幔包括更多的镁钙钛矿。通过高温高压下的X射线衍射原位测量，确定了GeO2的相变。

We developped a new diamond-anvil cell by modification of that used by the group lead by Dr. Mao at the Geophysical Laboratory, US.The new cell has more stable piston, suitable for the very high temperature experiments up to 3000-K at high pressures. Using this diamond-anvil cell, we obtained the experimental results below ; High pressure melting experiments on the pyrolite composition were conducted. The results showed that its melting curve is similar to MORB, supporting that the temperature of outer core is over 4000-K.Subsolidus phase equilibria studies were also done on the pyrolite composition. We found more iron is partitioned into Mg-rich perovskite in the-lower mantle than the earlier estimates. It suggests that the Earth's lower mantle includes more Mg-perovskite. The phase transition in GeO2 was determined by the in-situ X-ray diffraction measurements at high pressure and high temperature.