喀喇沁玻基橄辉岩中的磷酸盐质熔体及磷灰石

磷酸盐在本文讨论的坡基橄辉岩中以多种形式产生,有早期结晶的磷灰石斑晶;有熔离的磷酸盐质熔浆液滴;也有晚期穿入橄榄石斑晶的磷酸盐质细脉,表明元素磷活跃在岩浆演化的每一个阶段。磷酸盐质熔浆液滴的存在,说明磷酸盐质熔体可能是由于岩浆的熔离作用而形成的。沿着橄榄石晶格生长石出现的磷酸盐质玻璃细脉则进一步证实地幔中含磷流体不但存在,而且具有很强的活动性。

Phosphatic melt and apatite of the limburgite in Harqin

In the limburgite studied in this paper the phosphorus occurs in many types, such as early-stage crystallizing apatite phenocrysts, unmixing phosphatic molten lava drops, and late-stage phosphatic glassy stringers penetrating oliven phenocryst, indicating that element phosphorus is active in every stage of the magmatic evolution. The occurrence of phosphatic molten lava drop shows that the phosphatic melt can be formed by magmatic liquation. Phosphatic glassy stringers appeared along the lattice planes of olivine phenocrysts further demonstrate that phosphatic fluid is not only existing, but also very active in the mantle.