Paleozoic–Mesozoic Geology of South Island, New Zealand: Subduction-related Processes Adjacent to SE Gondwana
CONTAINS OPEN ACCESS
This volume presents a set of research papers that provide new data and interpretations of the Permian–Triassic terranes of SE Gondwana, now exposed in South Island, New Zealand. Following an introduction for general readers, a historical summary and a review of biostratigraphy, the individual papers primarily focus on the Permian magmatic arc of the Brook Street Terrane, the classic Permian Dun Mountain ophiolite and the Permian–Triassic Maitai Group sedimentary succession. The new results emphasize the role of subduction and terrane displacement adjacent to the Permo-Triassic Gondwana margin, and present fundamental insights into three crustal processes: subduction initiation, supra-subduction zone oceanic crust genesis and forearc basin evolution. The volume concludes with a wide-ranging summary and synthesis of the regional Cambrian to Early Cretaceous tectonostratigraphy of New Zealand's South Island in relation to the wider areas of Zealandia, East Australia and West Antarctica. The volume will interest geoscientists, including stratigraphers, sedimentologists, palaeontologists, igneous petrologists, geochemists, geochronologists and economic geologists, and is aimed at professional geologists and advanced students of geology.
Chapter 2: The path to understanding the central terranes of Zealandia
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Published:May 08, 2019
Abstract
This chapter traces the history of understanding the central terranes of New Zealand: Drumduan, Brook Street, Murihiku, Dun Mountain–Maitai and Caples. The terranes, mostly exposed in the South Island, are named from stratigraphic units of Late Paleozoic–Late Mesozoic age, including the Murihiku Supergroup, Brook Street Volcanics and Maitai groups, and the Dun Mountain ophiolite. European geologists in the mid-nineteenth century determined the stratigraphy of these rocks in the extremities of the island but in the succeeding half-century much effort was devoted to understanding widespread poorly fossiliferous ‘greywackes’: the ‘Maitai Controversy’. This was resolved in 1917 by palaeontology and the recognition of major faulting. In the 1940s the Alpine Fault, with an apparent 460 km dextral offset of the rocks at either end of the island, was recognized. In the following two decades, New Zealand was interpreted in terms of the geosynclinal hypothesis and then paired metamorphic belts. With plate tectonics, the basement rocks were assigned to terranes with the implication of being conveyed over considerable distances. The identification of source areas, coupled with the definition of the Cordilleran Median Batholith, has progressed the understanding of the present arrangement of the central terranes in the New Zealand part of Zealandia.
