The Kontum block is poorly known. It contains Precambrian metamorphic rocks with minimum ages of about 2.3 billion years, although the oldest well-dated widespread thermal event falls into the middle Cambrian Period (about 500 million years ago) and indicates the time of its final consolidation. The…

…Sino-Korean) and Yangtze paraplatforms, the Kontum block (in Southeast Asia), and the North Tarim fragment (also called Serindia; in western China). The orogenic zones consist of large tectonic collages that were accreted around the continental nuclei. Recognized zones are the Altaids, the Tethysides (further subdivided into the Cimmerides and the…

The Yangtze paraplatform and the Kontum block are believed to have been parts of Gondwanaland during the early Paleozoic, but they rifted away from it sometime in the Devonian Period (about 419 to 359 million years ago). Two other fragments in southeastern China, the Huan’an and Dongnanya, have basements that…