Annamia block

geology

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Last updated

June 18, 2026

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The Annamia block is a geological formation in Southeast Asia that was enlarged during the Paleozoic Era through the collision of island arcs. The earlier island arc docked along what is now the Annamese Cordillera in northern Vietnam during the Devonian period. A subsequent collision occurred along the Ma River during the early Carboniferous, causing significant deformation and thrusting. Subduction along the western margin of the Annamia block during the Carboniferous to Permian periods resulted in magmatism and mineralization, extending into the Malay Peninsula.1

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Asia
Paleozoic events in the Tethysides
…to what is called the Annamia block. The earlier island arc docked along a suture that now coincides with the Annamese Cordillera in northern Vietnam in the Devonian or slightly earlier. The later one collided along a suture zone farther to the north, along the present-day Ma River, during the…
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…to what is called the Annamia block. The earlier island arc docked along a suture that now coincides with the Annamese Cordillera in northern Vietnam in the Devonian or slightly earlier. The later one collided along a suture zone farther to the north, along the present-day Ma River, during the…
Read More