Monazite, titanite and zircon LA-ICP-MS petrochronology of the northern Borborema Province

Abstract

Linking radiometric ages to petrogenetic conditions is fundamental to understand the significance of geochronological data obtained from metamorphic rocks. These rocks often show multiple ages that are related to different stages of their pressure-temperature-deformation evolution. Connecting the ages to the different stages of metamorphic evolution is not a straightforward task but that can be done using a combined approach involving geochronology, trace element mineral chemistry and metamorphic petrology which has been referred to as petrochronology. This is a new branch of geosciences that has been flourishing in the last two decades together with the in-situ mineral analysis techniques. The proposed project aims to use monazite, titanite and zircon LA-ICP-MS petrochronology to determine the pressure-temperature-time evolution of the metasedimentary rocks of the Seridó Group and associated basement gneisses, in the northern Borborema Province, northeast Brazil. The project will be carried out at the LA-ICP-MS laboratory of the Goethe-University Frankfurt which is equipped with state-of-the-art LA-ICP-MS instrumentation, under the supervision of Dr. Axel Gerdes, an expert in in-situ mineral analysis by LA-ICP-MS. The proposed project is expected to provide unique insights into the Neoproterozoic tectonic evolution of the northern Borborema Province and consequently of the West Gondwana using a cutting-edge approach.