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The high pressure pelitic granulite with peak assemblage of garnet + kyanite + ternary feldspar + musco-vite + rutile was discovered in Qixia area in the Precambrian Jiaobei massif, where high pressure basic granulites are widely distributed. The metamorphic peak conditions for the pelitic granulite were calculated as T = 800—840℃ and P = 1.0—1.25 GPa on the basis of P-T pseudosection. The post peak P-T path is characterized first by an isothermal de-compression (ITD) pattern and then by an isobaric cooling (IBC) pattern, indicating a geodynamic process related to thinning of thickened continental crust.