Structural geometry and controls on basement-involved deformation in the northern Flinders Ranges, Adelaide Fold Belt, South Australia

Abstract

In the northern Flinders Ranges, Neoproterozoic and Cambrian sedimentary rocks were deformed and variably metamorphosed during the ca 500 Ma Cambro-Ordovician Delamerian Orogeny. Balanced and restored structural sections across the northern Flinders Ranges show shortening of about 10-20%. Despite the presence of suitable evaporitic detachment horizons at the basement-cover interface, the structural style is best interpreted to be thick-skinned involving basement with only a minor proportion of the overall shortening accommodated along stratigraphically controlled detachments. Much of the contractional deformation was localised by the inversion of former extensional faults such as the Norwest..