INSIGHTS INTO CRUSTAL PROCESSES WITHIN ARCS FROM GRANITOID ROCKS

Granitoid rocks commonly constitute a significant proportion of the magmatic record exposed within collisional belts that have been interpreted as former arcs. Information these rocks can provide include: 1. a record of both relative and absolute (using precise geochronology) changes over time in many parameters (e.g. mineralogy, geochemistry, isotopes); 2. an understanding of complex magmatic processes that occurred at various crustal levels and stages during arc formation, including partial melting P-T conditions; 3. as lower crustal probes, they can map large scale crustal boundaries or sutures; and, 4. constraining large scale geodynamic, tectonic and metallogenic processes within arcs. Examples of Mesozoic to Paleoproterozoic granitoid suites will help illustrate these insights.