论超高压变质的矿物学标志

The Mineralogical Criteria for Ultra-high Pressure Metamorphism

近20多年来,对超高压变质的研究日益深入。超高压变质的矿物学标志,已远远超出柯石英一种,结合实验矿物学的成果,发现许多新的矿物标志。可以归纳为以下3类:(1)矿物的多形转变,如柯石英和金刚石;(2)超高压矿物的出溶,如K-单斜辉石、majorite-镁铝榴石和高硅榍石;(3)超高压(高压)变质矿物或矿物组合,如多硅白云母、文石和菱镁矿等。文中介绍了这些矿物学标志的地质学和矿物学特征及应用前景。

In the past two decades, the study of ultra-high pressure metamorphism has been greatly advanced. The mineralogical criteria for the ultra-high pressure metamorphism have been increased far more than coesite alone. There are even more new mineralogical criteria of UHP metamorphism to be discovered in the combination with the new results of experimental mineralogy. The criteria hitherto recognized are of 3 categories ： （ 1 ） ultrahigh pressure polymorphism of minerals, such as, coesite and diamond ; （2） the exsolution of ultra-high pressure minerals, such as, K-clinopyroxene, majoritic-pyrope, high-silica sphene, and （3）ultrahigh pressure minerals and mineral association, such as, phengite, aragonite, magnesite etc. The present paper deals with the geological and mineralogical characteristics of these criteria and the perspective of their application.