Evidence for early extensional tectonics in the Proterozoic Mount Isa inlier, Australia

In the Proterozoic Mount Isa inlier, Queensland, Australia, structures belonging to an early brittle deformation event are overprinted and strongly disturbed by a phase of ductile east-west shortening. Many of these early structures have been attributed to thrusting, but data from the southern part of the inlier provide new evidence for extensional faulting. Analysis of the internal geometry of imbricates can provide a tool for the reconstruction of these strongly reworked Precambrian fault belts.