Zircon as a monitor of crustal growth

Zircon has long played a key role in crustal evolution studies as the pre-eminent U-Pb geochronometer. Recent advances in ana now permit investigations of complex grains at high spatial resolution, where the goal is to link zircon ages to other petrographic a information. Zircon can provide time-stamped 'snapshots' of hafnium and oxygen isotope signatures of magmas throughout Earth's history, even at the scale of individual growth zones within a single grain. This information is an invaluable help to geochemists trying to distinguish magma added new, mantle-derived material to the continental crust that merely recycled existing crust.