摘要
利用同步辐射和金刚石压腔(DAC)技术对天然矿物榍石进行原位高压能散模式X射线实验研究,结果表明榍石在3.9 GPa和10.9 GPa分别发生P 21/a→A 2/a和A 2/a→A 1结构相变,并首次确定10.9 GPa→25.1 GPa榍石结构很可能稳定保持A 1相。基于此认为榍石能在地球较深部位稳定存在,此外,本研究对探索地球深部T i和S i元素的地球化学行为也有一定帮助作用。
By using synchrotron radiation energy dispersive X-ray diffraction and diamond-anvilcell technology at room temperature,the in-situ high pressure structure of natural titanite had been studied experimentally. In the experiment,with increasing pressure,titanite transforms from P21/a to A2/a at the pressure of 3.9 GPa and another phase transition A2/a→ occurs at the pressure of 10. 9 GPa. It is quite possible that titanite possesses the same stable phase between 10. 9 GPa and 25.1 GPa. Based on the result of experiment and the P-T phase boundary reported in lit- erature,it is concluded that titanite could behave stably within some range of depth in the upper mantle,which corresponds to the existence of aluminous titanite in eclogite-zone. This research is helpful for the understanding of the geochemical behavior of titanium and silicon in the depth of Earth.
出处
《矿物岩石》
CAS
CSCD
北大核心
2006年第3期6-11,共6页
Mineralogy and Petrology
基金
国家自然科学基金(40272023)
关键词
榍石
高压
结构
同步辐射
high pressure
structure
titanite
synchrotron radiation
