| Ref ID: | 28388 |
|---|---|
| Ref Type: | Journal Article |
| Authors: | Nam, Tran Ngoc Sano, Yuji Terada, Kentaro Toriumi, Mitsuhiro Quynh, Phan Van Dung, Le Tien |
| Title: | First SHRIMP UPb zircon dating of granulites from the Kontum massif (Vietnam) and tectonothermal implications |
| Date: | 2001 |
| Source: | Journal of Asian Earth Sciences |
| DOI: | 10.1016/S1367-9120(00)00015-8 |
| Abstract: | The Kontum massif in Central Vietnam represents the largest continuous exposure of crystalline basement of the Indochina craton. The central Kontum massif is chiefly made of orthopyroxene granulites (enderbite, charnockite) and associated rocks of the Kannack complex. Mineral assemblages and geothermobarometric studies have shown that the Kannack complex has severely metamorphosed under granulite facies corresponding to PT conditions of 800850°C and 8±1 kbars. Twenty-three SHRIMP II UPb analyses of eighteen zircon grains separated from a granulite sample of the Kannack complex yield ca 254 Ma, and one analysis gives ca 1400 Ma concordant age for a zoned zircon core. This result shows that granulites of the Kannack complex in the Kontum massif have formed from a high-grade granulite facies tectonothermal event of Indosinian age (Triassic). The cooling history and subsequent exhumation of the Kannack complex during Indosinian times ranged from ∼850°C at ca 254 Ma to ∼300°C at 242 Ma, with an average cooling rate of ∼45°C/Ma. |
| Date Created: | 2/21/2012 |
| Volume: | 19 |
| Page Start: | 77 |
| Page End: | 84 |