Origin of the Northland Ophiolite, northern New Zealand: Discussion of new data and reassessment of the model

Abstract

This paper discusses new results from the Northland Ophiolite in northern New Zealand that indicate that it formed in a supra-subduction zone setting, c. 26-29 m.y. ago, and very near to its late Oligocene obduction site. This is in contrast to previous studies which have suggested that the ophiolite is a far-travelled igneous Cretaceous-Paleocene terrane. Cretaceous rocks formerly mapped as part of the ophiolite are minor and represent an autochthonous Late Cretaceous-Paleocene volcanic arc. The tectonic setting, age, and location of formation suggest that the ophiolite formed as part of the southernmost South Fiji Basin crust. Obduction of the Northland Ophiolite initiated subduction and volcanism resulting in the development of the Northland volcanic arc during the early Miocene. © The Royal Society of New Zealand 2004.