Antecedence of the Yarlung–Siang–Brahmaputra River, eastern Himalaya

摘要: Abstract At the eastern terminus of Himalayan orogen, distortion and capture southeast Asian drainage basins reflects regional patterns crustal strain due to indentation Indian Plate into Eurasia. After flowing eastward > 1000 km along southern margin Tibet, Yarlung–Siang–Brahmaputra River turns abruptly southward through syntaxis rapidly exhuming a scale antiform in an impressive 2 knickpoint. This conspicuous pattern coincidence focused fluvial incision rapid rock exhumation has been explained by ancestral, high-elevation Yarlung headward erosion tributary. However, recent observation Tibetan detritus Neogene foreland basin units complicates this explanation, requiring connection from Tibet prior estimated onset exhumation. We constrain sedimentary provenance deposited near Brahmaputra confluence using detrital zircon U–Pb geochronology. interpret significant presence Gangdese-age each unit indicate that was established during, or deposition Early Miocene. Our results precedes syntaxis, demonstrating potential for progressive coevolution uplift Namche Barwa massif.