The Western Gneiss Terrane is exposed along the western half of the northern margin of the Yilgarn Craton as the Narryer Gneiss Terrane, a composite of heavily polydeformed feldspathic metagranite and metasedimentary amphibolite-grade gneisses and migmatites, dated at greater than 3.3 Ga and up to 3.8 Ga in age, flanked by the Murgoo Gneiss Terrane (2.95 Ga), as well as sheets of 2.75 Ga to 2.6 Ga granite, obducted ophiolite sheets (the Trillbar Complex) and some 2.4 Ga to 2.0 Ga Proterozoic gneiss belts.