This paper studies the hydrous facies of mantle-derived megacrystclinopyroxenes and pyroxenes of xenoliths of pyroxenolite and spinel peridotite as well as garnetpyroxenolite in a kimberlitic lamprophyre pipe in Anyua...This paper studies the hydrous facies of mantle-derived megacrystclinopyroxenes and pyroxenes of xenoliths of pyroxenolite and spinel peridotite as well as garnetpyroxenolite in a kimberlitic lamprophyre pipe in Anyuan, Jiangxi, by Fourier Transform Infrared(FTIR). It explores the relationship between the water content of pyroxene on the one hand and itscomposition and source depths on the other hand. All the samples contain constitution water. Spectraof the clinopyroxene are dominated by two groups of bands: 3607-3630 cm^(-1) and 3522-3542 cm^(-1).Spectra of the orthopy-roxene are dominated by three groups of bands: 3410-3424 cm^(-1), 3510-3516cm^(-1) and 3560-3595 cm^(-1). The water content of the clinopyroxenes has a positive correlationwith their FeO and Al_2O_3 contents. The source depths of mantle-derived clinopyroxene megacrysts,pyroxenolite, spinel peritotite and garnet pyroxenelite increase gradually in order. The Al_2O_3 andwater contents of four pyroxenes have similar correlation with the source depths.展开更多
基金the National Natural Science Foundation of China(Grant No.49672105).
文摘This paper studies the hydrous facies of mantle-derived megacrystclinopyroxenes and pyroxenes of xenoliths of pyroxenolite and spinel peridotite as well as garnetpyroxenolite in a kimberlitic lamprophyre pipe in Anyuan, Jiangxi, by Fourier Transform Infrared(FTIR). It explores the relationship between the water content of pyroxene on the one hand and itscomposition and source depths on the other hand. All the samples contain constitution water. Spectraof the clinopyroxene are dominated by two groups of bands: 3607-3630 cm^(-1) and 3522-3542 cm^(-1).Spectra of the orthopy-roxene are dominated by three groups of bands: 3410-3424 cm^(-1), 3510-3516cm^(-1) and 3560-3595 cm^(-1). The water content of the clinopyroxenes has a positive correlationwith their FeO and Al_2O_3 contents. The source depths of mantle-derived clinopyroxene megacrysts,pyroxenolite, spinel peritotite and garnet pyroxenelite increase gradually in order. The Al_2O_3 andwater contents of four pyroxenes have similar correlation with the source depths.