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

Mountain domes rising to approximate to 6600 m along Tibet's Tanggula range herald the Eocene intrusion of calcalkaline granites into terranes accrete d 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 m arked a former northern boundary of the plateau, testifying to S-directed s ubduction of the Asian mantle, Such subduction would have developed soon af ter India's collision but long before the rise of the plateau's present rim s, along one of central Tibet's Mesozoic sutures.