The Burma Terrane or West Burma block was an isolated
Gondwana-derived
island arc within the
Tethys Ocean. The
terrane was in the upper plate of the
subduction zone since early
Cretaceous. It collided with
Insular India during the
Paleocene and continued to be pushed northwards, eventually colliding with mainland Asia. Much of western
Myanmar consists of the former Burma Terrane, hence the name "West Burma block".[1][2]
For a long time it was assumed that it was part of
Eurasia since
Mesozoic, but more recent
geochronology research suggest that it was located near the northwestern
Australia margin in the
Late Triassic, and
paleomagnetic data suggest that the block was at equatorial latitudes on a plave separate from Eurasia from the Cretaceous until the late
Eocene.[2]
Many of the small animals and plants that inhabited the Burma Terrane during the mid-Cretaceous are well-documented due to their exquisite preservation in
Burmese amber. Many of these animals were likely
endemic to the archipelago due to its isolation at the time, providing a rare comprehensive example of an insular fauna from the Mesozoic.[3] It has been inferred that most of these animals had Gondwanan origins, and that the Burma Terrane may have played an important biogeographic role by serving as a connection by transporting Gondwanan lineages northwards.[4]
See also
Hațeg Island, another Cretaceous island with a well-documented insular fauna