The Western Ailaoshan (WAL) Volcanic Belts mark the western boundary of the South China-Indochina Suture Zone along the Ailaoshan Fold Belt. Geochronological and geochemical evidence suggests that the WAL Volcanic Belts vary in ages and origins, and includes (1) L. Carboniferous-earliest M.-Permian (ca. 300-270. Ma) incipient backarc basin magmatism; (2) M. Permian (ca. 265. Ma) island arc/mature backarc basin magmatism; (3) early L. Permian (ca. 260-255. Ma) WAL-Indochina arc-continent collision and the associated syn-collisional granitic magmatism, as well as subsequent (4) E. Triassic (ca. 250-245. Ma) post-collisional magmatism. Regional geological comparison indicates that the post-L. Carboniferous WAL tectonic evolution was closely related to the Eastern Indochina Block. We present a new G-Plate geodynamic evolution model for the Ailaoshan Fold Belt and its surrounding South China-Indochina region, based on new and published U-Pb zircon ages, together with whole rock and Pb-isotope geochemical data.
- Western Ailaoshan (WAL) Volcanic Belts
- SE Asia
- Arc/backarc basin
- Arc–continent collision
- G-Plate tectonic reconstruction