Age limits for the Ubendian metamorphic episode in Northern Malawi

Abstract
Summary: The Nyika granite gives a U-Pb zircon age of 1970±30 Ma, which is a minimum age for the high-grade Ubendian metamorphism in Northern Malawi. Cordierite gneisses from the same region yield an Rb-Sr whole-rock isochron age of 1815±260 Ma. Because this age is believed to reflect the high-grade Ubendian metamorphism, the latter cannot be significantly older than about 2100 Ma.