Tectono-stratigraphic evolution and significance of the boundary between the Youanmi and the South West Terranes in the Archean Yilgarn Craton of Western Australia

In the Neoarchean Yilgarn Craton of Western Australia, the boundary between the South West and Youanmi Terranes was recently shifted to be congruent with several regional geological and geophysical features that suggest a major crustal discontinuity. The boundary now aligns with the western deformation front of a high-grade gneissic terrain known as the Corrigin Tectonic Zone. As terrane boundaries must be tectonically significant, an investigation into the Corrigin Tectonic Zone can provide insight into the amalgamation of the Yilgarn Craton in addition to testing the validity of the new terrane boundary. Continuous exposure across the new terrane boundary in the northern portion of the Corrigin Tectonic Zone around Toodyay and Northam provides an ideal natural laboratory to conduct this investigation. This project will integrate structural, metamorphic, isotopic and geochronologic analyses of the high-grade gneisses around the Toodyay-Northam area to construct a holistic model for the accretion of the South West and Youanmi Terranes, both testing the new boundary and providing insight into the development of the Yilgarn Craton with implications for wider Archean tectonics.

Involvement

Project Coordinator:

• Nico Thébaud

Collaborators:

• Tim Ivanic
• Raphael Quentin de Grommard

Participating Staff:

• Tony Kemp
• Naomi Tucker

Participating Student:

• Cat Gill

Additional Information

Participating Partner Research Orgs: GSWA

Funding Agencies: GSWA

Industry Participants: GSWA Raphael Quentin de Grommard, Tim Ivanic