The Gascoyne Complex is divided into two parts, the 1840–1620 Ma northern and central Gascoyne Complex, and the 2005–1970 Ma Glenburgh Terrane in the southern Gascoyne Complex. The two are separated by a major east-southeast trending fault, the Chalba Shear Zone. Rocks of the Glenburgh Terrane do not outcrop at surface north of the Chalba Shear Zone, but it is unclear as to whether or not rocks of this terrane floor all or part of the central and northern Gascoyne Complex.