42. South Tasman Basin and Borderlands: a Geophysical Summary R
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Hikurangi Plateau: Crustal Structure, Rifted Formation, and Gondwana Subduction History
Article Geochemistry 3 Volume 9, Number 7 Geophysics 3 July 2008 Q07004, doi:10.1029/2007GC001855 GeosystemsG G ISSN: 1525-2027 AN ELECTRONIC JOURNAL OF THE EARTH SCIENCES Published by AGU and the Geochemical Society Click Here for Full Article Hikurangi Plateau: Crustal structure, rifted formation, and Gondwana subduction history Bryan Davy Institute of Geological and Nuclear Sciences, P.O. Box 30368, Lower Hutt, New Zealand ([email protected]) Kaj Hoernle IFM-GEOMAR, Wischhofstraße 1-3, D-24148 Kiel, Germany Reinhard Werner Tethys Geoconsulting GmbH, Wischhofstraße 1-3, D-24148 Kiel, Germany [1] Seismic reflection profiles across the Hikurangi Plateau Large Igneous Province and adjacent margins reveal the faulted volcanic basement and overlying Mesozoic-Cenozoic sedimentary units as well as the structure of the paleoconvergent Gondwana margin at the southern plateau limit. The Hikurangi Plateau crust can be traced 50–100 km southward beneath the Chatham Rise where subduction cessation timing and geometry are interpreted to be variable along the margin. A model fit of the Hikurangi Plateau back against the Manihiki Plateau aligns the Manihiki Scarp with the eastern margin of the Rekohu Embayment. Extensional and rotated block faults which formed during the breakup of the combined Manihiki- Hikurangi plateau are interpreted in seismic sections of the Hikurangi Plateau basement. Guyots and ridge- like seamounts which are widely scattered across the Hikurangi Plateau are interpreted to have formed at 99–89 Ma immediately following Hikurangi Plateau jamming of the Gondwana convergent margin at 100 Ma. Volcanism from this period cannot be separately resolved in the seismic reflection data from basement volcanism; hence seamount formation during Manihiki-Hikurangi Plateau emplacement and breakup (125–120 Ma) cannot be ruled out. -
1. Leg 189 Summary1
Exon, N.F., Kennett, J.P., Malone, M.J., et al., 2001 Proceedings of the Ocean Drilling Program, Initial Reports Volume 189 1. LEG 189 SUMMARY1 Shipboard Scientific Party2 ABSTRACT The Cenozoic Era is unusual in its development of major ice sheets. Progressive high-latitude cooling during the Cenozoic eventually formed major ice sheets, initially on Antarctica and later in the North- ern Hemisphere. In the early 1970s, a hypothesis was proposed that cli- matic cooling and an Antarctic cryosphere developed as the Antarctic Circumpolar Current progressively thermally isolated the Antarctic continent. This current resulted from the opening of the Tasmanian Gateway south of Tasmania during the Paleogene and the Drake Pas- sage during the earliest Neogene. The five Leg 189 drill sites, in 2463 to 3568 m water depths, tested, refined, and extended the above hypothesis, greatly improving under- standing of Southern Ocean evolution and its relation with Antarctic climatic development. The relatively shallow region off Tasmania is one of the few places where well-preserved and almost-complete marine Cenozoic carbonate-rich sequences can be drilled in present-day lati- tudes of 40°–50°S and paleolatitudes of up to 70°S. The broad geological history of all the sites was comparable, although there are important differences among the three sites in the Indian Ocean and the two sites in the Pacific Ocean, as well as from north to south. In all, 4539 m of core was recovered with an excellent overall recov- ery of 89%, with the deepest core hole penetrating 960 m beneath the seafloor. The entire sedimentary sequence cored is marine and contains a wealth of microfossil assemblages that record marine conditions from the Late Cretaceous (Maastrichtian) to the late Quaternary and domi- nantly terrestrially derived sediments until the earliest Oligocene. -
Campbell Plateau: a Major Control on the SW Pacific Sector of The
Ocean Sci. Discuss., doi:10.5194/os-2017-36, 2017 Manuscript under review for journal Ocean Sci. Discussion started: 15 May 2017 c Author(s) 2017. CC-BY 3.0 License. Campbell Plateau: A major control on the SW Pacific sector of the Southern Ocean circulation. Aitana Forcén-Vázquez1,2, Michael J. M. Williams1, Melissa Bowen3, Lionel Carter2, and Helen Bostock1 1NIWA 2Victoria University of Wellington 3The University of Auckland Correspondence to: Aitana ([email protected]) Abstract. New Zealand’s subantarctic region is a dynamic oceanographic zone with the Subtropical Front (STF) to the north and the Subantarctic Front (SAF) to the south. Both the fronts and their associated currents are strongly influenced by topog- raphy: the South Island of New Zealand and the Chatham Rise for the STF, and Macquarie Ridge and Campbell Plateau for the SAF. Here for the first time we present a consistent picture across the subantarctic region of the relationships between front 5 positions, bathymetry and water mass structure using eight high resolution oceanographic sections that span the region. Our results show that the northwest side of Campbell Plateau is comparatively warm due to a southward extension of the STF over the plateau. The SAF is steered south and east by Macquarie Ridge and Campbell Plateau, with waters originating in the SAF also found north of the plateau in the Bounty Trough. Subantarctic Mode Water (SAMW) formation is confirmed to exist south of the plateau on the northern side of the SAF in winter, while on Campbell Plateau a deep reservoir persists into the following 10 autumn. -
Redalyc.Lost Terranes of Zealandia: Possible Development of Late
Andean Geology ISSN: 0718-7092 [email protected] Servicio Nacional de Geología y Minería Chile Adams, Christopher J Lost Terranes of Zealandia: possible development of late Paleozoic and early Mesozoic sedimentary basins at the southwest Pacific margin of Gondwanaland, and their destination as terranes in southern South America Andean Geology, vol. 37, núm. 2, julio, 2010, pp. 442-454 Servicio Nacional de Geología y Minería Santiago, Chile Available in: http://www.redalyc.org/articulo.oa?id=173916371010 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Andean Ge%gy 37 (2): 442-454. July. 2010 Andean Geology formerly Revista Geológica de Chile www.scielo.cl/andgeol.htm Lost Terranes of Zealandia: possible development of late Paleozoic and early Mesozoic sedimentary basins at the southwest Pacific margin of Gondwana land, and their destination as terranes in southern South America Christopher J. Adams GNS Science, Private Bag 1930, Dunedin, New Zealand. [email protected] ABSTRACT. Latesl Precambrian to Ordovician metasedimentary suecessions and Cambrian-Ordovician and Devonian Carboniferous granitoids form tbe major par! oftbe basemenl of soutbem Zealandia and adjacenl sectors ofAntarctica and southeastAustralia. Uplift/cooling ages ofthese rocks, and local Devonian shallow-water caver sequences suggest tbal final consolidation oftbe basemenl occurred tbrough Late Paleozoic time. A necessary consequence oftlris process would have been contemporaneous erosion and tbe substantial developmenl of marine sedimentary basins al tbe Pacific margin of Zealandia. -
Bathymetry of the New Zealand Region
ISSN 2538-1016; 11 NEW ZEALAND DEPARTMENT OF SCIENTIFIC AND INDUSTRIAL RESEARCH BULLETIN 161 BATHYMETRY OF THE NEW ZEALAND REGION by J. W. BRODIE New Zealand Oceanographic Institute Wellington New Zealand Oceanographic Institute Memoir No. 11 1964 This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/3.0/ Fromispiece: The survey ship HMS Penguin from which many soundings were obtained around the New Zealand coast and in the south-west Pacific in the decade around 1900. (Photograph by courtesy of the Trustees, National Maritime Museum, Greenwich.) This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/3.0/ NEW ZEALAND DEPARTMENT OF SCIENTIFIC AND INDUSTRIAL RESEARCH BULLETIN 161 BATHYMETRY OF THE NEW ZEALAND REGION by J. W. BRODIE New Zealand Oceanographic Institute Wellington New Zealand Oceanographic Institute Memoir No. 11 1964 Price: 15s. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/3.0/ CONTENTS Page No. ABSTRACT 7 INTRODUCTION 7 Sources of Data 7 Compilation of Charts 8 EARLIER BATHYMETRIC INTERPRETATIONS 10 Carte Gen�rale Bathymetrique des Oceans 17 Discussion 19 NAMES OF OCEAN FLOOR FEATURES 22 Synonymy of Existing Names 22 Newly Named Features .. 23 FEATURES ON THE CHARTS 25 Major Morphological Units 25 Offshore Banks and Seamounts 33 STRUCTURAL POSITION OF NEW ZEALAND 35 The New Zealand Plateau 35 Rocks of the New Zealand Plateau 37 Crustal Thickness Beneath the New Zealand Plateau 38 Chatham Province Features 41 The Alpine Fault 41 Minor Irregularities on the Sea Floor 41 SEDIMENTATION IN THE NEW ZEALAND REGION . -
Thurston Island
RESEARCH ARTICLE Thurston Island (West Antarctica) Between Gondwana 10.1029/2018TC005150 Subduction and Continental Separation: A Multistage Key Points: • First apatite fission track and apatite Evolution Revealed by Apatite Thermochronology ‐ ‐ (U Th Sm)/He data of Thurston Maximilian Zundel1 , Cornelia Spiegel1, André Mehling1, Frank Lisker1 , Island constrain thermal evolution 2 3 3 since the Late Paleozoic Claus‐Dieter Hillenbrand , Patrick Monien , and Andreas Klügel • Basin development occurred on 1 2 Thurston Island during the Jurassic Department of Geosciences, Geodynamics of Polar Regions, University of Bremen, Bremen, Germany, British Antarctic and Early Cretaceous Survey, Cambridge, UK, 3Department of Geosciences, Petrology of the Ocean Crust, University of Bremen, Bremen, • ‐ Early to mid Cretaceous Germany convergence on Thurston Island was replaced at ~95 Ma by extension and continental breakup Abstract The first low‐temperature thermochronological data from Thurston Island, West Antarctica, ‐ fi Supporting Information: provide insights into the poorly constrained thermotectonic evolution of the paleo Paci c margin of • Supporting Information S1 Gondwana since the Late Paleozoic. Here we present the first apatite fission track and apatite (U‐Th‐Sm)/He data from Carboniferous to mid‐Cretaceous (meta‐) igneous rocks from the Thurston Island area. Thermal history modeling of apatite fission track dates of 145–92 Ma and apatite (U‐Th‐Sm)/He dates of 112–71 Correspondence to: Ma, in combination with kinematic indicators, geological -
Pliocene-Pleistocene Evolution of Sea Surface and Intermediate Water
PUBLICATIONS Paleoceanography RESEARCH ARTICLE Pliocene-Pleistocene evolution of sea surface 10.1002/2016PA002954 and intermediate water temperatures Key Points: from the southwest Pacific • Reconstructed Tasman Sea surface and Antarctic Intermediate Water Erin L. McClymont1, Aurora C. Elmore1, Sev Kender2,3, Melanie J. Leng2,3, Mervyn Greaves4, and temperatures fi 4,5 • Long-term cooling trends from ~3.0 to Henry Elder eld 2.6 Ma and from 1.5 Ma to present 1 2 • Complex subtropical front displacement Department of Geography, Durham University, Durham, UK, Centre for Environmental Geochemistry, School of and subantarctic cooling trends since Geography, University of Nottingham, Nottingham, UK, 3British Geological Survey, Nottingham, UK, 4Department of Earth Pliocene Sciences, University of Cambridge, Cambridge, UK, 5Deceased 19 April 2016 Abstract Over the last 5 million years, the global climate system has evolved toward a colder mean state, Correspondence to: E. L. McClymont, marked by large-amplitude oscillations in continental ice volume. Equatorward expansion of polar waters [email protected] and strengthening temperature gradients have been detected. However, the response of the mid latitudes and high latitudes of the Southern Hemisphere is not well documented, despite the potential importance for Citation: climate feedbacks including sea ice distribution and low-high latitude heat transport. Here we reconstruct the McClymont, E. L., A. C. Elmore, S. Kender, Pliocene-Pleistocene history of both sea surface and Antarctic Intermediate Water (AAIW) temperatures on M. J. Leng, M. Greaves, and H. Elderfield orbital time scales from Deep Sea Drilling Project Site 593 in the Tasman Sea, southwest Pacific. We confirm (2016), Pliocene-Pleistocene evolution of sea surface and intermediate water overall Pliocene-Pleistocene cooling trends in both the surface ocean and AAIW, although the patterns are temperatures from the southwest complex. -
The Age and Origin of Miocene-Pliocene Fault Reactivations in the Upper Plate of an Incipient Subduction Zone, Puysegur Margin
RESEARCH ARTICLE The Age and Origin of Miocene‐Pliocene Fault 10.1029/2019TC005674 Reactivations in the Upper Plate of an Key Points: • Structural analyses and 40Ar/39Ar Incipient Subduction Zone, Puysegur geochronology reveal multiple fault reactivations accompanying Margin, New Zealand subduction initiation at the K. A. Klepeis1 , L. E. Webb1 , H. J. Blatchford1,2 , R. Jongens3 , R. E. Turnbull4 , and Puysegur Margin 5 • The data show how fault motions J. J. Schwartz are linked to events occurring at the 1 2 Puysegur Trench and deep within Department of Geology, University of Vermont, Burlington, VT, USA, Now at Department of Earth Sciences, University continental lithosphere of Minnesota, Minneapolis, MN, USA, 3Anatoki Geoscience Ltd, Dunedin, New Zealand, 4Dunedin Research Centre, GNS • Two episodes of Late Science, Dunedin, New Zealand, 5Department of Geological Sciences, California State University, Northridge, Northridge, Miocene‐Pliocene reverse faulting CA, USA resulted in short pulses of accelerated rock uplift and topographic growth Abstract Structural observations and 40Ar/39Ar geochronology on pseudotachylyte, mylonite, and other Supporting Information: fault zone materials from Fiordland, New Zealand, reveal a multistage history of fault reactivation and • Supporting information S1 uplift above an incipient ocean‐continent subduction zone. The integrated data allow us to distinguish • Table S1 true fault reactivations from cases where different styles of brittle and ductile deformation happen • Figure S1 • Table S2 together. Five stages of faulting record the initiation and evolution of subduction at the Puysegur Trench. Stage 1 normal faults (40–25 Ma) formed during continental rifting prior to subduction. These faults were reactivated as dextral strike‐slip shear zones when subduction began at ~25 Ma. -
Oceanography and Marine Zoology of the New Zealand Subantarctic
44 ECOLOGY OF SUBANTARCTIC ISLANDS The highest temperatures recorded at Auck- REFERENCES land Is. and at Campbell 1. are much the same, approximately 65°F., and are 12°F. DE LISLE, J. F., 1964. Weather and climate of Campbell higher than that at Macquarie 1. (Table 12). Island. Pacific Ins. Monograph 7: 34-44. The extreme minimum at Macquarie I. is 10°F. lower than that at Port Ross. FABRICIUS, A. F., 1957. Climate of the Subantarctic Islands. In Meteorology of the Antarctic, ed. Van Sea temperatures at Campbell 1. are about Rooy. Weather Bureau, South Africa. 3°F. warmer than the earth temperatures at 12 inches in mid winter and about I!OF. colder FALLA, R. A., 1948. The outlying islands of New Zea- in midsummer (Table 13). land. N.Z. Geographer 4; 127-154. HITCHINGS, M. G., 1949. Campbell Island. A subantarc- TABLE 13. Mean monthly earth and sea tic meteorological station. Weather 4: 389-92. temperatures. Earth temp. Sea temp. MARSHALL, 0., 1909. The Meteorology of Campbell at 1 foot Campbell Auckland Island. In The Subantarctic Islands of New Zea- Campbell L I. Is. land, ed. C. Chilton. Philosophical Institute of Jan. 51.0 49.5 50.8 Canterbury. 2 vols. Feb. 50.3 49.t 51.0 Mar. 48.5 48.5 50.5 MAWSON, D., 1915. The home of the blizzard. Heine- man, London. 2 vols. A~ ~ ~ ~ May 43.2 45.3 47.4 NEWMAN, W., 1929. Tabulated and reduced records of June 40.3 43.2 46.1 the Macquarie Island Station. In Aust. -
Exploration of New Zealand's Deepwater Frontier * GNS Science
exploration of New Zealand’s deepwater frontier The New Zealand Exclusive Economic Zone (EEZ) is the 4th largest in the world at about GNS Science Petroleum Research Newsletter 4 million square kilometres or about half the land area of Australia. The Legal Continental February 2008 Shelf claim presently before the United Nations, may add another 1.7 million square kilometres to New Zealand’s jurisdiction. About 30 percent of the EEZ is underlain by sedimentary basins that may be thick enough to generate and trap petroleum. Although introduction small to medium sized discoveries continue to be made in New Zealand, big oil has so far This informal newsletter is produced to tell the eluded the exploration companies. industry about highlights in petroleum-related research at GNS Science. We want to inform Exploration of the New Zealand EEZ has you about research that is going on, and barely started. Deepwater wells will be provide useful information for your operations. drilled in the next few years and encouraging We welcome your opinions and feedback. results would kick start the New Zealand deepwater exploration effort. Research Petroleum research at GNS Science efforts have identified a number of other potential petroleum basins around New Our research programme on New Zealand's Zealand, including the Pegasus Sub-basin, Petroleum Resources receives $2.4M p.a. of basins in the Outer Campbell Plateau, the government funding, through the Foundation of deepwater Solander Basin, the Bellona Basin Research Science and Technology (FRST), between the Challenger Plateau and Lord and is one of the largest research programmes in GNS Science. -
Geological Timeline - Tasmania
GEODIVERSITY Geological Timeline - Tasmania Tasmania’s spectacular geodiversity has contributed Chains of volcanoes form across Tasmania, including Mt directly to the islands’ biodiversity. The State’s Read Volcanic Belt, a highly significant mineralised belt. geodiversity is a result of continental drift, ice ages, humid, hot conditions and earthquakes occurring over 443 - 408 Million Years Ago more than a billion years. Extensive erosion and subsequent deposition form the sandstones and conglomerates of West Coast Range and A very brief and summarised account of Tasmania’s Denison Range. geological history is outlined below. Although Tasmania is referred to frequently, it was not until about 45 Tasmania partly covered by a warm tropical sea and part million years ago that Tasmania began to look anything of a much larger land mass of Gondwana situated near like it does today. the equator. Gordon Limestone formed from the debris of marine life. Today this limestone outcrops in parts of 4600 - 635 Million Years Ago the Franklin and Gordon River valleys and around Mole The Earth formed about 4600 million years ago. Creek, where subsequent disolving by water has formed many karst and cave systems. Little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth’s history. This is 408 - 360 Million Years Ago because traces of the geological heritage of Precambrian Warm shallow continental seas provide a hospitable times have been erased by relentless subsequent erosion. environment for marine life of all kinds. Coral reefs made First evidence of simple life forms, cyanobacteria, the their first appearance during this time, and first bony fish building blocks for stromatolites, are among the oldest appear. -
South-East Marine Region Profile
South-east marine region profile A description of the ecosystems, conservation values and uses of the South-east Marine Region June 2015 © Commonwealth of Australia 2015 South-east marine region profile: A description of the ecosystems, conservation values and uses of the South-east Marine Region is licensed by the Commonwealth of Australia for use under a Creative Commons Attribution 3.0 Australia licence with the exception of the Coat of Arms of the Commonwealth of Australia, the logo of the agency responsible for publishing the report, content supplied by third parties, and any images depicting people. For licence conditions see: http://creativecommons.org/licenses/by/3.0/au/ This report should be attributed as ‘South-east marine region profile: A description of the ecosystems, conservation values and uses of the South-east Marine Region, Commonwealth of Australia 2015’. The Commonwealth of Australia has made all reasonable efforts to identify content supplied by third parties using the following format ‘© Copyright, [name of third party] ’. Front cover: Seamount (CSIRO) Back cover: Royal penguin colony at Finch Creek, Macquarie Island (Melinda Brouwer) B / South-east marine region profile South-east marine region profile A description of the ecosystems, conservation values and uses of the South-east Marine Region Contents Figures iv Tables iv Executive Summary 1 The marine environment of the South-east Marine Region 1 Provincial bioregions of the South-east Marine Region 2 Conservation values of the South-east Marine Region 2 Key ecological features 2 Protected species 2 Protected places 2 Human activities and the marine environment 3 1.