摘 要: | Granulite in eastern Shandong is mainly exposed in Laixi. Pingdu, Changyi and Anqiu, and the diagnosticmineral assemblage is Opx+Cpx+Hb+PI±Q±Sca. The appearance of orthopyroxene and Its coexistence withhornblende indicate that the reaction Hb+Q=Opx+Cpx+PI+H_2O did not proceed completely and thereforethese rocks belong to the amphibolite-granulite transition facies. i.e., belonging to hornblende-granulitesubfacics. According to the data obtained from such geothermometers and geobarometers as Opx-Cpx,Opx-Hb. Cpx-Hb, Hb-PI. Sca-PI and Fe-Ti oxides, it has been determined that the temperature of the mainmetamorphic stage was 720-810℃, the pressure 0.5 GPa and fo_210~(-15.5), showing a geothermal gradient of41-46℃/km, and thus the rocks belong to "low-temperature" and low-pressure granulite facies.
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