An Eocene magmatic belt across central Tibet: mantle subduction triggered by the Indian collision?

Mountain domes rising to ≈ 6600 m along Tibet’s Tanggula range herald the Eocene intrusion of calcalkaline granites into terranes accreted much earlier. Together with coeval, cogenetic volcanics, such intrusives, which have similar crystallization and cooling ages, may be part of an ESE‐trending belt cutting central Tibet in half. This magmatic belt may have marked a former northern boundary of the plateau, testifying to S‐directed subduction of the Asian mantle. Such subduction would have developed soon after India’s collision but long before the rise of the plateau’s present rims, along one of central Tibet’s Mesozoic sutures.