Myanmar and Asia united, Australia left behind long ago

Detrital Zircons Dismember Sibumasu in East Gondwana

“…Taken together ( n = 922 from 10 samples), pre‐Triassic detrital zircons from Sumatra are dominated by two major age populations of circa 1,300–1,000 Ma (peaks at 1,170 and 1,070 Ma) and 590–510 Ma, along with a minor peak at circa 935 Ma (Figure a). This age pattern is comparable with that of West Burma (Figure c; Sevastjanova et al, ; Tang, ). By contrast, compiled detrital zircons from Sibusima (including Baoshan, Tengchong, East Burma, and Thailand; Burrett et al, ; Cai et al, ; G. W. Li et al, ; D. P. Li, Luo, et al, ) exhibit two major age populations of circa 980–860 Ma and 575–465 Ma, with circa 1,300–1,000 Ma zircons as a subordinate population (Figure e).…”

“…East Sumatra is characterized by a dominant late Mesoproterozoic age population along with a minor early Neoproterozoic age population (Figure a); clearly dissimilar to Sibusima (Sibumasu excluding East Sumatra) that is dominated by early Neoproterozoic zircons with minor late Mesoproterozoic grains (Figure e). These age distributions occur persistently in Cambrian (Burrett et al, ; G. W. Li et al, ), Ordovician to Silurian (Cai et al, ), Carboniferous to Permian (Cai et al, ; D. P. Li, Luo, et al, ), and even Triassic to Cenozoic (G. W. Li et al, ; Sevastjanova et al, ; Tang, ) strata in different localities of Sibusima, probably reflecting steady/long‐term source characteristics rather than sudden shifts in or mixing between sources. Therefore, such contrasting provenance signatures between East Sumatra and Sibusima indicate that their detrital materials are most probably derived from distinct sources.…”

“…New detrital zircon U‐Pb‐Hf isotopic data in this study and compiled detrital zircon U‐Pb data are available in the supporting information (Burrett et al, ; Cai et al, ; Cawood & Nemchin, ; Ding et al, ; Gardner et al, ; Gehrels et al, , , ; Hsu, ; Leier et al, ; G. W. Li et al, ; D. P. Li, Luo, et al, ; G. W Li, Sandiford, et al, ; McQuarrie et al, ; Myrow et al, , ; Pullen et al, ; Sevastjanova et al, ; Sircombe & Freeman, ; Tang, ; Veevers et al, ; Zhu et al, ). Special thanks to Shan Li in Institute of Geology, Chinese Academy of Geological Sciences, for helping collect samples during fieldtrips.…”

“…To determine the source terranes for East and West Sumatra, we compiled detrital zircon data from the Lhasa (Gehrels et al, ; Leier et al, ; G. W. Li et al, ; G. W Li, Sandiford, et al, ; Pullen et al, ; Zhu et al, ), South Qiangtang (C. Y. Dong et al, ; Gehrels et al, ; Pullen et al, , ; Zhu et al, ), Tethyan and High Himalayas (Ding et al, ; Gehrels et al, , ; McQuarrie et al, ; Myrow et al, , ; Zhu et al, ), West Burma (Sevastjanova et al, ; Tang, ), northern Sibumasu (Burrett et al, ; Cai et al, ; G. W. Li et al, ; D. P. Li, Luo, et al, ), and Western Australia (Cawood & Nemchin, ; Gardner et al, ; Sircombe & Freeman, ; Veevers et al, ; and Geoscience Australia data at http://www.ga.gov.au/geochron-sapub-web/geochronology/shrimp/search.htm). Detrital zircon data from Precambrian to early Paleozoic strata in the above regions, if available, were primarily used, supplemented by those from younger strata showing comparable age patterns.…”

Chapter 1 Introduction to the geology of Myanmar

“…Audley-Charles (1988) suggested that this block, together with other crustal blocks, separated from the northern margin of Gondwana in the region of north Australia during the Jurassic, and collided with eastern Myanmar in the Cretaceous. Sevastjanova et al (2016) have shown by U-Pb analysis of detrital zircons in the Triassic Pane Chaung Formation that the West Myanmar Block was already attached to Southeast Asia by Late Triassic times. Studies of detrital zircons from the Triassic Langjiexue Group in the Tethyan Himalaya have been found to have similar age spectra to that of the Pane Chaung Formation of Myanmar, suggesting that the latter unit was also deposited on the Indian Plate.…”