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Encyclopedia of geology, five volume set, volume 1 5 (encyclopedia of geology series) ( PDFDrive ) 1846

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NEW ZEALAND Figure Palaeogeographical reconstructions of New Zealand at approximately (A) 100 Ma, (B) 65 Ma, (C) 30 Ma, and (D) 10 Ma Brown, inferred land including schematic island arc chains; black lines, present day coastlines of North and South Islands and the Alpine Fault On these reconstructions, the Alpine fault divides the South Island into eastern and western parts (Reproduced with permission from Lee DE, Lee WG, and Mortimer N (2001) Where and why have all the flowers gone? Depletion and turnover in the New Zealand Cenozoic angiosperm flora in relation to palaeogeography and climate Australian Journal of Botany 49: 341 356.) Maitai, Caples, Rakaia, and Pahau terranes Carboniferous conodonts are known from a limestone in the Rakaia Terrane, but the age range of clastic rocks in Eastern Province terranes is from Permian to Early Cretaceous (Figure 5) The Eastern Province terranes are thus entirely younger than the Western Province terranes and represent accretion of material to Gondwana in the Mesozoic The Brook Street Terrane is a Permian subductionrelated isotopically primitive pyroxene-rich basaltdominated volcanic pile and volcaniclastic apron, in places up to 14 km thick, which is intruded by Permian layered gabbros and trondhjemite plutons that are now part of the Median Batholith New Zealand’s only known Glossopteris, a Gondwanan leaf fossil, occurs in the Brook Street Terrane The Murihiku Terrane comprises a 9–13 km Late Permian to Late Jurassic volcaniclastic marine succession of sandstone with lesser conglomerates, mudstones, and tuffs It has the simplest internal structure of all the Mesozoic New Zealand terranes, a broad synclinorium that is traceable for 450 km through the North and South Islands The Maitai Terrane consists of the eastern Early Permian (285–275 Ma, according to uranium–lead dating of zircon) Dun Mountain Ophiolite Belt, which is unconformably overlain by km of wellstratified Late Permian to Middle Triassic volcaniclastic sedimentary rocks The ophiolite originated in a near-arc setting The Brook Street, Murihiku and Maitai terranes are adjacent to each other as a Permian–Triassic arc, fore-arc, and exhumed near-arc ophiolite, respectively The Caples, Bay of Islands, and Rakaia terranes contrast with the aforementioned Eastern Province terranes in that their Permian–Jurassic clastic sequences are tectonically imbricated with ocean-floor basalt, chert, and limestone associations; all three terranes grade into the pumpellyite–actinolite to amphibolite facies Haast Schist Deposition occurred as submarine-fan deposits in lower trench-slope basins, before juxtaposition in an accretionary

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