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All the data presented in this paper for the bulk compositions, mineral chemistry and trace element geochemistry of ultramafic inclusions suggest that the most lherzolite inclusions represent fertile mantle samples, and the black websterite inclusions represent granulite samples from the lower crust. The lherzolito inclusions equilibrate at the temperature in the restricted range from 980 to 1120℃ and have a considerable variation in equilibrium pressure (i. e. between 12.5 to 24 kb) at calculated temperatures, and the black websterite inclusions have the relatively low equilibrium P-T conditions (850-950℃. 8 kb). As compared with both ocean and shield geotherms, the paleogeotherm defined by the lherzolite inclusions has much steeper slope at depths less than 100 km. It may be inferred that the least depleted mantle is probably located immediately beneath the region studied.
All the data presented in this paper for the bulk compositions, mineral chemistry and trace element geochemistry of ultramafic inclusions suggest that the most lherzolite inclusions represent fertile mantle samples, and the black websterite inclusions represent granulite samples from the lower crust. The lherzolito inclusions equilibrate at the temperature in the restricted range from 980 to 1120 ° C and have a considerable variation in equilibrium pressure (ie between 12.5 and 24 kb) at the calculated temperatures, and the black websterite inclusions have the relatively low equilibrium PT conditions (850-950 ° C. 8 kb). As compared with both ocean and shield geotherms, the paleootherm defined by the lherzolite inclusions has much steeper slope at depths less than 100 km. It may be inferred that the least depleted mantle is probably located immediately beneath the region studied.