Initial opening of the Neotethyan Ocean in SE Asia: Constraints from Triassic magmatism and sedimentation

How the Neotethyan Ocean evolved and extended southwards into Southeast Asia remains controversial. The paleographical correlation between India SE Asian blocks and/or terranes before opening of Neotethys initial time is still unknown. lack this knowledge hampers our further understanding tectonic evolution global Neotethys. Here we present a combined study on Triassic magmatism in Tengchong Block sedimentation Myitkyina area, located two sides Tagaung-Myitkyina Ophiolite Belt northern Myanmar. Our results coupled with previous data demonstrate that continental magmatic arc developed sedimentary sequence was part Tethyan Himalayan Langjiexue Group India. Moreover, provided important detrital inputs to whole Such provenance best explanation for Permian−Triassic zircons Langjuexue Group. Together, propose Ophiolites Myanmar are relics rather than Mesotethyan (Bangong-Nujiang Ocean) Asia, Early Jurassic 200−190 Ma. Then, earliest (185−165 Ma) intra-oceanic akin Izu-Bonin-Mariana West Pacific, soon after Late