In situ U-Pb dating combined with SEM images on zircon crystals represent a powerful tool to reconstruct metamorphic and magmatic evolution of basements recording a long and complex geological history [1-3]. The development of high spatial and mass resolution microprobes (e.g., LA-ICP-MS, SIMS, SHRIMP) allows in-situ measurements of U–Pb ages in micro domains smaller than 30-50 microns [4, 5]. The growth of zircon crystals, evidenced by their internal microtextures, can be easily revealed by SEM imaging by Cathodoluminescence (CL) and Variable Pressure Secondary Electrons (VPSE) detectors on separated grains or in situ within a polished thin rock section [6,4,7]. Therefore it is possible to date different domains of single crystals, which may record magmatic or metamorphic events of the rock’s geological history [8,4]. In acidic magmatic rocks abundant zircon crystals provide precise age data about magma emplacement and origin of source indicating the geodynamic context and the pertinence of terranes forming the continental crust.
In situ U-Pb dating combined with SEM imaging on zircon - an analytical bond for effective geological reconstruction
FORNELLI, Annamaria;MICHELETTI, FRANCESCA
2014-01-01
Abstract
In situ U-Pb dating combined with SEM images on zircon crystals represent a powerful tool to reconstruct metamorphic and magmatic evolution of basements recording a long and complex geological history [1-3]. The development of high spatial and mass resolution microprobes (e.g., LA-ICP-MS, SIMS, SHRIMP) allows in-situ measurements of U–Pb ages in micro domains smaller than 30-50 microns [4, 5]. The growth of zircon crystals, evidenced by their internal microtextures, can be easily revealed by SEM imaging by Cathodoluminescence (CL) and Variable Pressure Secondary Electrons (VPSE) detectors on separated grains or in situ within a polished thin rock section [6,4,7]. Therefore it is possible to date different domains of single crystals, which may record magmatic or metamorphic events of the rock’s geological history [8,4]. In acidic magmatic rocks abundant zircon crystals provide precise age data about magma emplacement and origin of source indicating the geodynamic context and the pertinence of terranes forming the continental crust.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
