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Ten spinel-lherzolite inclusions and one olivine-websterite inclusion, which were collectedfrom Fujian, Jiangsu, Hebei and Yunnan Provinces, consist of olivine (Fo_(87.7-91.2)), enstatite(En_(87.3-89.7)), Cr-diopside and spinel. According to the Mg/(Mg+Fe~(2+)) ratios in the rocksand their mineralogies, they are designated to the Cr-diopside type. The websterite is com-posed of bronzite (En_(71.9)) and augite, while the gabbro-norite consists of hypersthene (En_(68.9))and augite, belonging to the Al-augite type. The geothermos of spinel-lherzolites were calculated with four geothermometric methods,giving a temperature range of 925°-1,072℃. However, according to P. R. A. Wells’ method,temperatures range from 845° to 1,014℃, and by D. H. Lindsly’s approach, from 716°-974℃. Pressures range from 15.1 to 19.8 kb. Genetically, Spinel-lherzolites and olivine-websterite are thought to have been derived fromresidual mantle material by partial melting at approximately 1,000℃ and at a depth of about50--70 km. Websterite and gabbro-norite may be products of the crystallization-differentia-tion of alkali basaltic magma.
Ten spinel-lherzolite inclusions and one olivine-websterite inclusion, which were collected from Fujian, Jiangsu, Hebei and Yunnan Provinces, consist of olivine (Fo 87.7-91.2), enstatite (En 87.3-89.7) spinel. According to the Mg / (Mg + Fe ~ (2+)) ratios in the rocks and their mineralogies, they are designated to the Cr-diopside type. The websterite is com- posed of bronzite (En_ (71.9)) and augite , while the gabbro-norite consists of hypersthene (En_ (68.9)) and augite, belonging to the Al-augite type. The geothermos of spinel-lherzolites were calculated with four geothermometric methods, giving a temperature range of 925 ° -1,072 ° C. However, according to PRA Wells’ method, temperatures range from 845 ° to 1,014 ° C, and by DH Lindsly’s approach, from 716 ° -974 ° C. Pressures range from 15.1 to 19.8 kb. Genetically, Spinel-lherzolites and olivine-websterite are thought to have been derived fromresidual mantle material by partial melting at approximately 1,000 ℃ and at a Depth of about 50--70 km. Websterite and gabbro-norite may be products of the crystallization-differentia-tion of alkali basaltic magma.