The structural geology of the Mount Burnett dolomite deposit, North-West Nelson

Abstract

At Mt Burnett in the Wakamarama Range of North-west Nelson, a thick layer of dolomite is intercalated with an Ordovician carbonate sequence associated with Cambrian schists. A map and cross section are presented. Mesoscopic structures have been used to elucidate the major structures, which consist of an antiform flanked on either side by synforms. These folds are shear and/or flow folds depending on the lithology involved, and a foliation is developed parallel to the axial plane. In most cases original bedding in the carbonate rocks has been transposed by the foliation. Later deformation has produced localised folding of the foliation and subsequently the Paleozoic rocks have been exposed by erosion following strong over-thrusting on the regional Wakamarama Fault. This movement probably continued into late Pleistocene times.