阿波罗-17(70017—291)高钛月海玄武岩的化学组成及其成因的探讨  

A PRELIMINARY STUDY ON CHEMICAL COMPOSITION AND GENESIS OF APOLLO 17 HIGH-Ti MARE BASALT

作　　者：王道德 欧阳自远 

出　　处：《地球化学》1981年第4期365-372,共8页Geochimica

摘　　要：Chemical, petrological and mineralogical studies on 70017-291 Mare basalt indicate that the mare basalt belongs to Type B of A-17 basalts with a texture of plagioclasepoikilitic ilmenite basalt. The mean chemical composition of this basalt is as follows:SiO2 39.01, TiO2 11.32, Al2O3 9.24, FeO 18.52, MgO 8.61, CaO 10.86 (%). INAA measurements were made on the basalt for major, minor and trace elements. Seven pyroxene grains in the Apollo 17 were also analyzed by microprobe. They show two compositions, one for pigeonite, and the other for augite-subcalicaugite. The mean composition of pigeonite is Wo10.85, En59.33 Fs30, and that of augite-subcalic augite Wo25 En41.5Fs38.3. Plagioclase grains have a composition ranging from An30 to An96. The plagioclase contains detectable iron (averaging 0.74%), potassium (0.089% in average) and titanium(averaging 0.16%). The mean composition of ihnenite is TiO2 53.98%, FeO 41.02%,Al2O3 0.21%, MgO 2.41%, Cr2O3 0.74%. The Ti-high mare basalt (70017-291) was formed by partial melting of the early cumulates through assimilation and migmatization. On the whole, mare basalts seem to be of multigenesis.Chemical, petrological and mineralogical studies on 70017-291 Mare basalt indicate that the mare basalt belongs to Type B of A-17 basalts with .a texture of plagioclase-poikilitic ilmenite basalt. The mean chemical composition of this basalt is as follows: Si02 39.01, Ti02 11.32, Al203 9.24, FeO 18.52, MgO 8.61, CaO 10.86 (%). INAA measurements were made on the basalt for major, minor and trace elements. Seven pyroxene grains in the Apollo 17 were also analyzed by microprobe. They show two compositions, one for pigeonite, and the other for augite-subcalicaugite. The mean com-position of pigeonite is Wo10.65 En59.35 Fs30, and that of augite-subcalic augite Wo25 En41.5 Fs33.5. Plagioclase grains have a composition ranging from An80 to An96. The plagioclase contains detectable iron (averaging 0.74%), potassium ,(0.089% in average) and titanium (averaging 0.16%). The mean composition, of; ilmenite is TiO2 53.98%, FeO 41-.02%, A1203 0.21%, MgO 2.41%, Cr2O3 0.74%. The Ti-high mare basalt (70017-291) was formed by partial melting of the early cumulates through assimilation and migmatiza-tion. On the whole, mare basalts seem to be of multigenesis.

关 键 词：玄武岩 化学组成 月球探测 微量元素 

分 类 号：P588.145[天文地球—岩石学] P184.5[天文地球—地质学]