| Abstract: |
Precambrian granulite facies rocks occur over an area of 100km in the eastern part of the Kontum Massif of Vietnam. This unusual occurrence of Precambrian high grade metamorphic rocks is separated from the closest similar rocks to the west in the Indian Eastern Ghats by over 2000km. The intervening area is occupied by the Mesozoic-Cenozoic Burma-Malay orogen. In the reconstruction of Precambrian Gondwanaland a granulite facies mobile belt can be traced from Sri Lanka, India, Antarctica through to Australia. However a considerable gap remains between the Indian-Eastern Ghats section and the Albany-Fraser Belt of S. W. Australia. This gap has been suggested to be, in part, filled by similar rocks found in the Shillong Plateau, Assam. High grade metamorphic rock of uncertain age also occur in the Mogok area in central Burma. The tectonic history of the Indochina Block in the Precambrian is debatable, however some latest Precambrian paleotectonic interpretations join this block and the Tibetan, Chinese, and Iranian Blocks with Precambrian Gondwanaland. If the Kannack Complex is proved to be Archaean/Proterozoic, preliminary and incomplete information suggest that it could have been placed adjacent to the Eastern Ghats of India in the earliest Precambrian.
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