碱金属元素对山东蓝宝石结晶的促进作用研究

A study on the mechanism that the alkali elements promote the crystal of sapphire

目的研究碱金属元素对山东蓝宝石结晶的促进作用。方法对山东蓝宝石寄主玄武岩的主量、微量、稀土元素以及蓝宝石包裹体中的主量元素进行分析,再对碱金属氧化物在岩浆网络中的化学行为进行研究。结果晶出山东蓝宝石的母岩浆源于富集地幔的低度熔融,并在蓝宝石结晶前或者结晶过程中与下地壳发生过强烈的壳—幔交互作用,这种交互作用为母源岩浆提供了充足的硅铝质和碱金属氧化物;其中的铝质为蓝宝石的结晶提供了物质基础,而碱金属氧化物则极大地促进了蓝宝石的结晶。结论碱金属元素对山东蓝宝石的结晶有积极的推动作用。

Aim To study the promotion action by alkali elements to the crystal of sapphire. Methods Analyse the main trace and rare earth elements content of Shandong sapphire-hosted basalt and the main elements content of the inclusions in sapphire,then study the chemical action of the alkali elements in magma net. Results Shandong sapphire may have crystalized in a kind of magma which originated from the small-extent melting of enrichment mantle, and this magma must have undergone the violent interaction with under crust before or during the crystal of sapphire, which supplied mother magma a mass of Al, Si and alkali elements. Alkali is perhaps the essential matter for the crystal of sapphire, and the alkali elements can promote the crystal of sapphire on a great extent. Conclusion Alkali elements have the positive effect on the crystal of sapphire.