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The Zhongshan Station of China is located in the Larsemann Hills, East Antarctica. Low pressure granulite facies gneisses together with late granites are outcroped in the region. Three biotite samples from a garnet segregation, a syenogranite and a granite-pegmetite were measured with ~(40)Ar/~(39)Ar incremental heating technique. Biotites from the garnet segregation give an ~(40)Ar/~(39)Ar plateau age of 504±1Ma. Biotites from the syenogranite yield an ~(40)Ar/~(39)Ar plateau age of 494±1 Ma. Biotites from the granite-pegmatite give an ~(40)Ar/~(39)Ar plateay age of 486±1Ma. They verify 500 Ma thermal event called “Pan African event” by previous K-Ar and Rb-Sr data. They are cooling ages of the biotites when the paleogeotherm of the area droped to the K-Ar closure temperature for biotite.
The Zhongshan Station of China is located in the Larsemann Hills, East Antarctica. Low pressure granulite facies gneisses together with late granites are outcroped in the region. Three biotite samples from a garnet segregation, a syenogranite and a granite-pegmetite were measured with ~ ( 40) Ar / ~ (39) Ar incremental heating technique. Biotites from the garnet segregation give an ~ (40) Ar / ~ (39) Ar plateau age of 504 ± 1 Ma. Biotites from the syenogranite yield an ~ ~ (39) Ar plateau age of 494 ± 1 Ma. Biotites from the granite-pegmatite give an ~ (40) Ar / ~ (39) Ar plateay age of 486 ± 1Ma. They verify 500 Ma thermal event called “Pan African event ”by previous K-Ar and Rb-Sr data. They are ages of the biotites when the paleootherm of the area droped to the K-Ar closure temperature for biotite.