DOCSLIB.ORG

32-1 Arculus.Pdf

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
32-1 Arculus.Pdf OceTHE OFFICIALa MAGAZINEn ogOF THE OCEANOGRAPHYra SOCIETYphy CITATION Arculus, R.J., M. Gurnis, O. Ishizuka, M.K. Reagan, J.A. Pearce, and R. Sutherland. 2019. How to cre- ate new subduction zones: A global perspective. Oceanography 32(1):160–174, https://doi.org/ 10.5670/oceanog.2019.140. DOI https://doi.org/10.5670/oceanog.2019.140 PERMISSIONS Oceanography (ISSN 1042-8275) is published by The Oceanography Society, 1 Research Court, Suite 450, Rockville, MD 20850 USA. ©2019 The Oceanography Society, Inc. Permission is granted for individuals to read, download, copy, distribute, print, search, and link to the full texts of Oceanography articles. Figures, tables, and short quotes from the magazine may be republished in scientific books and journals, on websites, and in PhD dissertations at no charge, but the materi- als must be cited appropriately (e.g., authors, Oceanography, volume number, issue number, page number[s], figure number[s], and DOI for the article). Republication, systemic reproduction, or collective redistribution of any material in Oceanography is permitted only with the approval of The Oceanography Society. Please contact Jennifer Ramarui at [email protected]. Permission is granted to authors to post their final pdfs, provided byOceanography , on their personal or institutional websites, to deposit those files in their institutional archives, and to share the pdfs on open-access research sharing sites such as ResearchGate and Academia.edu. DOWNLOADED FROM HTTPS://TOS.ORG/OCEANOGRAPHY SPECIAL ISSUE ON SCIENTIFIC OCEAN DRILLING: LOOKING TO THE FUTURE HOW TO CREATE NEW SUBDUCTION ZONES A Global Perspective By Richard J. Arculus, Michael Gurnis, Osamu Ishizuka, Mark K. Reagan, Julian A. Pearce, and Rupert Sutherland Sand and gravel shed by turbidite flows from volcanoes of the nascent Izu-Bonin-Mariana island arc, recovered at Site U1438 of IODP Expedition 351, in the Amami- Sankaku Basin. Photo credit: Richard Arculus 160 Oceanography | Vol.32, No.1 ABSTRACT. The association of deep-sea trenches—steeply angled, planar zones where INTRODUCTION earthquakes occur deep into Earth’s interior—and chains, or arcs, of active, explosive In the late nineteenth century, surveying volcanoes had been recognized for 90 years prior to the development of plate tectonic expeditions discovered that there were theory in the 1960s. Oceanic lithosphere is created at mid-ocean ridge spreading cen- great depths in the ocean. Their mea- ters and recycled into the mantle at subduction zones, where down-going lithospheric surements included spot soundings by plates dynamically sustain the deep-sea trenches. Study of subduction zone initiation is HMS Challenger in 1873 in the Puerto a challenge because evidence of the processes involved is typically destroyed or buried Rico Trench (7,087 m) and in 1875 in by later tectonic and crust-forming events. In 2014 and 2017, the International Ocean the Mariana Trench (8,184 m). The deep- Discovery Program (IODP) specifically targeted these processes with three back-to- est sounding at that time (8,500 m) was back expeditions to the archetypal Izu-Bonin-Mariana (IBM) intra-oceanic arcs and reported by Captain George Belknap one expedition to the Tonga-Kermadec (TK) system. Both subduction systems were on USS Tuscarora; it marks the first rec- initiated ~52 million years ago, coincident with a proposed major change of Pacific ognition of a linear deep, the Kurile- plate motion. These expeditions explored the tectonism preceding and accompany- Kamchatka Trench. By the 1930s and ing subduction initiation and the characteristics of the earliest crust-forming magma- 1940s, it was realized that trenches are tism. Lack of compressive uplift in the overriding plate combined with voluminous associated with all of the volcanic arcs basaltic seafloor magmatism in an extensional environment indicates a large com- encircling the Pacific, plus those of ponent of spontaneous subduction initiation was involved for the IBM. Conversely, Indonesia, the Mediterranean, and the a complex range of far-field uplift and depression accompanied the birth of the TK Atlantic (Antilles and South Sandwich; system, indicative of a more distal forcing of subduction initiation. Future scientific Figure 1). The association of these volca- ocean drilling is needed to target the three-dimensional aspects of these processes nic island chains with ocean deeps, and at new converging margins. their positions parallel to one another, had FIGURE 1. Global distribution of island arcs based on the Global Topography base (https://topex.ucsd.edu/marine_topo/). Main panel is centered on the Pacific, with inset showing the Mediterranean and the Middle East. Oceanography | March 2019 161 previously attracted attention. For exam- Earth processes is considerable. It has even destroyed through tectonic erosion, ple, Sollas (1903) demonstrated that an been shown, for example, that most of the burial, thermal and volcanic overprint- arc of islands could represent the outcrop driving force behind global plate tecton- ing, and other processes at convergent trace of a planar fault at Earth’s spherical ics derives from subducted plate (“slab”) plate boundaries (e.g., Stern, 2004). surface. Continentward-dipping zones of pull rather than “ridge push” (Forsyth The surge in ocean floor exploration earthquake foci beneath Japan (Wadati, and Uyeda, 1975; Conrad and Lithgow- of the 1950s–1960s, concurrent with the 1931), the Andes, and Tonga-Kermadec Bertelloni, 2002). The surface of a litho- development of plate tectonic theory, was (Benioff, 1949) were recognized as huge spheric plate carries a carapace of sedi- accompanied by the realization that the thrust faults (Lake, 1931). Benioff (1954) ment and fluid into Earth’s interior that compositions of oceanic and continen- further suggested that the frictional heat reflects the interactions of rocks with the tal crust are fundamentally different. The generated along these faults was respon- atmosphere, hydrosphere, and biosphere. assemblage of rock types (chert- basalt- sible for the volcanism of the island Some of these components are returned diabase- gabbro- variably serpentinized and continental arcs developed above to the exterior as wedges of sediment that peridotite) collectively called an ophiolite earthquake zones. have been scraped off at the trenches, became key for understanding the origin In the 1920s to 1930s, submarine- through forearc vents (Fryer, 2012), or and development of much more inaccessi- borne gravity measurements in the via magma genesis within or above the ble in situ oceanic crust (e.g., Gass, 1968). Indonesian region led by Dutch geo- downgoing slab. Improvements in analytical techniques physicist F. Vening Meinesz revealed All major plate boundaries are ephem- for petrological, geochemical, and isoto- major negative gravity anomalies along eral; they may lengthen or shorten, move pic studies of magma types led to the real- the Sumatra-Java-Banda trenches relative to one another, or be created and ization that subduction zone inputs result (Umbgrove, 1945) similar to those sub- destroyed through time (Dewey, 1975). in trace element and mineralogical char- sequently recognized to also exist over Subduction zones can vanish, as evident acteristics in convergent margins magmas other deep-sea trenches. Understanding in the Cenozoic demise of the trench asso- that are distinct from those of magmas at the significance of radioactive heating ciated with the subduction of the Farallon divergent margins (e.g., Pearce and Cann, of Earth, earthquake and igneous activ- Plate below North America (Atwater, 1973). Convergent margin characteris- ity, and the characteristics of arc-trench 1970). By using records of paleomag- tics derive from the input of subducted systems was critical in development of a netic reversals preserved in oceanic crust, slab-sourced fluids into the regions of arc convective hypothesis to account for con- observations of seafloor fabric, and a vari- magma generation in the wedge of man- tinental drift (Holmes, 1928). However, ety of other onshore and offshore data, tle lying between a subducted slab and it was not until the development of the these events have been reconstructed for the overriding plate. plate tectonic theory (Hess, 1962; Wilson, the geologic past, with confidence for The seminal proposition by Miyashiro 1965; McKenzie and Parker, 1967) that periods where we have records of the his- (1973) that suggested the Troodos the significance of deep-sea trenches tory of plate motions (e.g., back to the Complex of western Cyprus, an arche- and associated earthquakes and volca- Jurassic; Seton et al., 2012), and less so typal ophiolite, formed in an island nism became generally understood to for older times (Matthews et al., 2016a). arc rather than at a mid-ocean ridge mark the return (subduction) of tec- Knowledge of the processes by which prompted a torrent of criticism but also a tonic plates (portions of lithosphere) into plate boundaries initiate and die is crit- re-examination of the concepts of crustal Earth’s interior. Subduction zones can ical to gaining a fuller understanding of formation at convergent boundaries. now be defined as locations where two how plate tectonics works and how it has Miyashiro’s hypothesis was founded on plates converge, as one sinks below the shaped our planet through geologic time. the similarity of the major element geo- other into Earth’s interior. At Earth’s sur- And while we have a good understand- chemistry of the Troodos Complex with face, the interface between the two plates ing of the initiation and development island arcs rather than that of mid-ocean is typically marked by a deep-sea trench; of divergent plate boundaries (i.e., mid- ridges. In particular, the presence of with increasing depth, subduction zones ocean ridges) and straightforward obser- glassy volcanic rocks containing unusu- can be recognized and traced by dipping vational opportunities for their study, the ally high MgO (>10 wt%) with inter- and planar groupings of earthquakes that same is not true for convergent boundar- mediate (i.e., andesitic) silica (~55 wt% are associated both with rocks and sedi- ies and their associated subduction zones.
Load more

Recommended publications
  • Vulnerable Marine Ecosystems – Processes and Practices in the High Seas Vulnerable Marine Ecosystems Processes and Practices in the High Seas
    ISSN 2070-7010 FAO 595 FISHERIES AND AQUACULTURE TECHNICAL PAPER 595 Vulnerable marine ecosystems – Processes and practices in the high seas Vulnerable marine ecosystems Processes and practices in the high seas This publication, Vulnerable Marine Ecosystems: processes and practices in the high seas, provides regional fisheries management bodies, States, and other interested parties with a summary of existing regional measures to protect vulnerable marine ecosystems from significant adverse impacts caused by deep-sea fisheries using bottom contact gears in the high seas. This publication compiles and summarizes information on the processes and practices of the regional fishery management bodies, with mandates to manage deep-sea fisheries in the high seas, to protect vulnerable marine ecosystems. ISBN 978-92-5-109340-5 ISSN 2070-7010 FAO 9 789251 093405 I5952E/2/03.17 Cover photo credits: Photo descriptions clockwise from top-left: Acanthagorgia spp., Paragorgia arborea, Vase sponges (images courtesy of Fisheries and Oceans, Canada); and Callogorgia spp. (image courtesy of Kirsty Kemp, the Zoological Society of London). FAO FISHERIES AND Vulnerable marine ecosystems AQUACULTURE TECHNICAL Processes and practices in the high seas PAPER 595 Edited by Anthony Thompson FAO Consultant Rome, Italy Jessica Sanders Fisheries Officer FAO Fisheries and Aquaculture Department Rome, Italy Merete Tandstad Fisheries Resources Officer FAO Fisheries and Aquaculture Department Rome, Italy Fabio Carocci Fishery Information Assistant FAO Fisheries and Aquaculture Department Rome, Italy and Jessica Fuller FAO Consultant Rome, Italy FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS Rome, 2016 The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.
    [Show full text]
  • Proposal to Study Subduction Initiation in Northern Zealandia Tim Stern1
    Proposal to study subduction initiation in northern Zealandia Tim Stern1, Rupert Sutherland2 1 Victoria University of Wellington; 2 GNS Science, Lower Hutt [email protected] Back-arc regions of subduction zones contain sedimentary records that hold clues to the subduction initiation process, and provide complementary insights to fore-arc studies (e.g. Izu-Bonin-Mariana and Tonga). The basins and sedimentary platforms northwest of New Zealand record onset of the Tonga –Kermadec (TK) system during the Eocene- Oligocene (see Gurnis et al. white paper). We propose (mainly) marine geophysical studies that will reveal clues as to how and why TK, and Hikurangi, subduction started. Key features that require study are: Norfolk Ridge (NR); New Caledonia Trough (NCT); Taranaki-Wanganui basins; and Three Kings Ridge (TKR). The NR is where surface convergence was associated with initial subduction. What was the vergence and timing of thrusting, what vertical motions took place, and how do these observations compare and discriminate alternate geodynamic model predictions? The New Caledonia Trough lies adjacent to Norfolk Ridge, was deformed in the subduction initiation event and subsided with large magnitude (Sutherland and al., 2010) that is precisely quantified (1.5 km) at its southern end near the north end of Taranaki Basin (Baur et al., 2013). What was the regional timing of NCT subsidence in relation to other aspects of subduction initiation, and what is its significance? Does the 1.5 km of Oligocene “platform subsidence” seen in oil company drill hole data from South Taranaki Basin at ~ 30 Ma (Stern and Holt, 1994) have a common cause as that in the NCT ? If so, the process occurs on a ~1000 km scale and is clearly geodynamically significant.
    [Show full text]
  • Avian Evolution, Gondwana Biogeography and the Cretaceous
    doi 10.1098/rspb.2000.1368 Avian evolution, Gondwana biogeography and the Cretaceous±Tertiary mass extinction event Joel Cracraft Department of Ornithology, American Museum of Natural History, Central Park West at 79th Street, NewYork, NY 10024, USA ( [email protected]) The fossil record has been used to support the origin and radiation of modern birds (Neornithes) in Laurasia after the Cretaceous^Tertiary mass extinction event, whereas molecular clocks have suggested a Cretaceous origin for most avian orders.These alternative views of neornithine evolution are examined using an independent set of evidence, namely phylogenetic relationships and historical biogeography. Phylogenetic relationships of basal lineages of neornithines, including ratite birds and their allies (Palaeognathae), galliforms and anseriforms (Galloanserae), as well as lineages of the more advanced Neoaves (Gruiformes, Caprimulgiformes, Passeriformes and others) demonstrate pervasive trans- Antarctic distribution patterns.The temporal history of the neornithines can be inferred from fossil taxa and the ages of vicariance events, and along with their biogeographical patterns, leads to the conclusion that neornithines arose in Gondwana prior to the Cretaceous^Tertiary extinction event. Keywords: Neornithes; avian evolution; biogeography; Gondwana; Cretaceous^Tertiary extinction marker of neornithine beginnings.The fact that the 1. INTRODUCTION preponderance of the fossils are found in North America The relationships of modern birds, or Neornithes, to non- and Europe is taken as evidence that most higher taxa of avian theropods and Mesozoic pre-neornithine avian birds diversi¢ed on the Laurasian landmass and had lineages, is now well established (Chiappe 1995; Padian little, if anything, to do with Gondwana (Feduccia 1995). & Chiappe 1998; Chiappe et al.
    [Show full text]
  • Morphology and History of the Kermadec Trench–Arc–Backarc
    Marine Geology 159Ž. 1999 35±62 www.elsevier.nlrlocatermargeo Morphology and history of the Kermadec trench±arc±backarc basin±remnant arc system at 30 to 328S: geophysical profile, microfossil and K±Ar data Peter F. Ballance a,), Albert G. Ablaev b, Igor K. Pushchin b, Sergei P. Pletnev b, Maria G. Birylina b, Tetsumaru Itaya c, Harry A. Follas a,1, Graham W. Gibson a,2 a UniÕersity of Auckland, PriÕate Bag 92019, Auckland, New Zealand b Pacific Oceanological Institute, 43 Baltiyskaya Street, VladiÕostok 690041, Russian Federation c Research Institute of Natural Sciences, Okayama UniÕersity of Science, 1-1 Ridai-cho, Okayama 700, Japan Received 8 January 1998; accepted 27 November 1998 Abstract Knowledge of the time span of arc activity, essential for correct tectonic reconstructions, has been lacking for the Kermadec arc system, but is supplied in this paper through study of microfossils contained in dredge samples, and K±Ar ages on dredged basalt clasts. The Kermadec system at south latitudes 30 to 328 in the southwest Pacific comprises from west to east the Colville RidgeŽ. remnant arc , Havre Trough Ž backarc basin . , Kermadec Ridge Ž. active arc and Kermadec TrenchŽ site of west-dipping subduction of Pacific plate lithosphere beneath the Australian plate. Data are presented from two traversesŽ. dredge, magnetic, single-channel seismic across the whole system. An important transverse tectonic boundary, the 328S Boundary, lies between the two traverse lines and separates distinct northernŽ. 32±258S and southern Ž.32±368S sectors. The northern sector is shallower and well sedimented with broad ridges and a diffuse backarc basin.
    [Show full text]
  • Oceanography of the Coral and Tasman Seas*
    Oceanogr. Mar. Biol. Ann. Rev., 1967,5,49-97 Harold Barnes, Ed. Publ. George Auen and UnWin Ltd., London OCEANOGRAPHY OF THE CORAL AND TASMAN SEAS* H. ROTSCHI AND L. LEMASSON Ofice de la Recherche Scientijque et Technique Outre-Mer, Centre de Nouméa BATHYMETRY AND TOPOGRAPHY OF THE COR_-L AND TASMAN SEAS The Coral Sea extends between the Solomon Islands on the northeast, New Caledonia and the New Hebrides Islands on the east, and the coast of Queensland on the west while to the south it is limited by the Tasman Sea. To the northwest it communicates with the Arafura Sea by the shallow Torres Strait; at the Solomon Archipelago it opens on to the equatorial zone of the Pacifìc Ocean and comes under the influence of the central and tropical Pacific both in crossing the Archipelago of the New Hebrides and to the south of New Caledonia. The Coral Sea has a mean depth of the order of 2400 m with a maximum of 9140 m in the New Britain Trench. The Tasman Sea is limited to the north by the Coral Sea, to the east by New Zealand, to the west by the coast of New South Wales and to the south by Tasmania; in the south it is largely under the influence of the Antarctic Ocean and in the west under that of the central South Pacific. The maximum depth is 5943 m. BATHYMETRY As is apparent from the most recent bathymetric chart of these oceans (Menard, 1964) they have a complicated structure which is particularly evident in the Coral Sea.
    [Show full text]
  • “SEAMOUNT” Database: Recent Updates and Its Potential Use for Ecological Risk Assessment
    New Zealand Aquatic Environment and Biodiversity Report No. 27 2008 ISSN 1176-9440 New Zealand’s “SEAMOUNT” database: recent updates and its potential use for ecological risk assessment A. A. Rowden M. Oliver M. R. Clark K. Mackay New Zealand's "SEAMOUNT" database: recent updates and its potential use for ecological risk assessment A. A. Rowden M. Oliver M. R. Clark K. Mackay NIWA Private Bag 14901 Wellington 6241 New Zealand Aquatic Environment and Biodiversity Report No. 27 2008 Published by Ministry of Fisheries Wellington 2008 ISSN 1176-9440 © Ministry of Fisheries 2008 Citation: Rowden, A.A.; Oliver, M.; Clark, M.R.; Mackay, K. (2008). New Zealand's "SEAMOUNT" database: recent updates and its potential use for ecological risk assessment. New Zealand Aquatic Environment and Biodiversity Report No. 27. 49 p. This series continues the Marine Biodiversity Biosecurity Report series which ceased with No.7 in February 2005. EXECUTIVE SUMMARY Rowden, A.A.; Oliver, M.; Clark, M.R.; Mackay, K (2008). New Zealand's "SEAMOUNT" database: recent updates and its potential use for ecological risk assessment. New Zealand Aquatic Environment and Biodiversity Report No. 27. 49 p. I) NIWA's SEAMOUNT database was enhanced in order to improve its utility for fisheries managers addressing issues around the effects of bottom trawling on "seamounts". 2) Forty-one additional data fields were erected and populated to create a second version of the database (now with a total of 72 data fields). 3) Access to the updated database is restricted at present to NIW A and MFish. Broader public access is planned by 2010.
    [Show full text]
  • Eocene–Miocene Volcanoes Near Zealandia's Rifted Continental Margin
    1 Australian Journal of Earth Sciences Archimer 2021, Volume 68, Issue 3, Pages 368-380 https://doi.org/10.1080/08120099.2020.1805007 https://archimer.ifremer.fr https://archimer.ifremer.fr/doc/00646/75834/ The Norfolk Ridge seamounts: Eocene–Miocene volcanoes near Zealandia’s rifted continental margin Mortimer N. 1, * , Patriat Martin 2, Gans P. B. 3, Agranier Arnaud 4, Chazot Gilles 4, Collot Julien 5, Crundwell M. P. 6, Durance P. M. J. 6, Campbell H. J. 6, Etienne S. 5 1 GNS Science, Dunedin, New Zealand 2 IFREMER, Unité Géosciences Marines, Plouzané, France 3 Geological Sciences, University of California, Santa Barbara, USA 4 dLaboratoire Domaines Océaniques UMR/CNRS 6538, IUEM, Université de Bretagne Occidentale, Technopôle Brest-Iroise, Plouzané, France 5 Service Géologique de Nouvelle-Calédonie, Nouméa, New Caledonia 6 GNS Science, Lower Hutt, New Zealand * Corresponding author : N. Mortimer, email address : [email protected] Abstract : New age and geochemical data are used to investigate the origin of a ∼670 km-long line of eight seamount volcanoes along the western side of the Norfolk Ridge between New Caledonia and New Zealand. Altered lavas and limestones were dredged from three volcanoes during the 2015 Volcanic Evolution of South Pacific Arcs cruise of N/O l’Atalante, so a total of four, including the northernmost and southernmost, have now been directly sampled and analysed. Dating of lava and volcanic breccia clasts by Ar–Ar methods gives north-to-south ages from these sites of 31.3 ± 0.6, 33 ± 5, 21.5 ± 1.0 and 26.3 ± 0.1 Ma.
    [Show full text]
  • Protea Seamount Cluster 2020
    Front cover image credits: ACEP, Linda Harris, Steve Benjamin, Geoff Spiby, Melanie Wells Protea Seamount Cluster Proposed EBSA Description Abstract The Protea Seamount Cluster is in the south Atlantic abyss off the SSW flank of the Agulhas continental shelf, within the South African EEZ. It is a unique feature in that it is the only seamount cluster in the south Atlantic abyss in South Africa’s EEZ. The seamounts support more productivity and diversity compared to adjacent sites, and offer a site for migratory species to aggregate around. Notably, the Protea Seamount Cluster contains vulnerable and sensitive ecosystems and species, some of which are threatened, e.g. the site is visited by regionally Critically Endangered leatherback turtles. It is in good condition given the currently low anthropogenic pressure in the area, promoting the importance of its protection. This EBSA is particularly relevant for its: Uniqueness and rarity; Importance for threatened or declining species and habitats; Vulnerability and sensitivity; and Naturalness. Introduction The Protea Seamount Cluster focus area lies on the SSW flank of the Agulhas continental shelf: an oceanic plateau that extends several hundreds of kilometres south of South Africa. The focus area is south west of the Browns Bank EBSA, entirely within the South African EEZ. The site includes the base of the lower slope, but falls mainly within the south Atlantic abyss. Late Eocene volcanism created the seamount cluster in this focus area, including Protea and Argentina Seamounts (among others). The Agulhas Current, which flows south-westward along the eastern coast of South Africa, has its retroflection in this area.
    [Show full text]
  • Western South Pacific Regional Workshop in Nadi, Fiji, 22 to 25 November 2011
    SPINE .24” 1 1 Ecologically or Biologically Significant Secretariat of the Convention on Biological Diversity 413 rue St-Jacques, Suite 800 Tel +1 514-288-2220 Marine Areas (EBSAs) Montreal, Quebec H2Y 1N9 Fax +1 514-288-6588 Canada [email protected] Special places in the world’s oceans The full report of this workshop is available at www.cbd.int/wsp-ebsa-report For further information on the CBD’s work on ecologically or biologically significant marine areas Western (EBSAs), please see www.cbd.int/ebsa south Pacific Areas described as meeting the EBSA criteria at the CBD Western South Pacific Regional Workshop in Nadi, Fiji, 22 to 25 November 2011 EBSA WSP Cover-F3.indd 1 2014-09-16 2:28 PM Ecologically or Published by the Secretariat of the Convention on Biological Diversity. Biologically Significant ISBN: 92-9225-558-4 Copyright © 2014, Secretariat of the Convention on Biological Diversity. Marine Areas (EBSAs) The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the Convention on Biological Diversity concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of Special places in the world’s oceans its frontiers or boundaries. The views reported in this publication do not necessarily represent those of the Secretariat of the Areas described as meeting the EBSA criteria at the Convention on Biological Diversity. CBD Western South Pacific Regional Workshop in Nadi, This publication may be reproduced for educational or non-profit purposes without special permission from the copyright holders, provided acknowledgement of the source is made.
    [Show full text]
  • Seal Quality and Distribution in the Southern Taranaki Basin Late Cretaceous to Eocene Section and Implications for Hydrocarbon Trapping
    SEAL QUALITY AND DISTRIBUTION IN THE SOUTHERN TARANAKI BASIN LATE CRETACEOUS TO EOCENE SECTION AND IMPLICATIONS FOR HYDROCARBON TRAPPING ________________________________________________________________ A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geology in the University of Canterbury by J. Coyle University of Canterbury 2018 ________________________________________________________________ Contents Abstract ................................................................................................................................................... V Acknowledgments .................................................................................................................................. VI 1. Introduction .................................................................................................................................... 1 1.1 Project Aims and Outline ........................................................................................................ 1 1.2 Geological Overview ............................................................................................................... 4 1.3 Seals ........................................................................................................................................ 5 1.4 Previous and Current Exploration ........................................................................................... 6 2. Overview of the Taranaki Basin .....................................................................................................
    [Show full text]
  • Breathing New Life Into Postmortem Analysis: the Testing And
    BREATHING NEW LIFE INTO POSTMORTEM ANALYSIS: THE TESTING AND FORMALIZATION OF A METHODOLOGY FOR THE IDENTIFICATION OF KEY FAILURE MODES IN DRY HOLES by Jack M. Samis A thesis submitted to the Faculty and the Board of Trustees of the Colorado School of Mines in partial fulfillment of the requirements for the degree of Master of Science (Geology). Golden, Colorado Date __________________________ Signed: __________________________ Jack M. Samis Signed: __________________________ Alexei V. Milkov Thesis Advisor Golden, Colorado Date __________________________ Signed: __________________________ Dr. Steve Enders Professor and Head Department of Geology and Geological Engineering ii ABSTRACT The petroleum exploration industry relies on various subsurface data and interpretations to minimize risk and uncertainties and maximize gains. Dry holes provide a wealth of useful subsurface information. However, far too often a company drills a dry hole and either does not conduct a postdrill analysis (postmortem), or incorrectly determines the failure mode. The purpose of this study is to formalize and test the applicability of a postdrill methodology (a decision tree) that helps identify the main failure mode for dry segments tested by conventional wells. Use of this decision tree allows the interpreter to evaluate and identify specific failure modes such as reservoir presence, reservoir deliverability, structure, seal, source maturity, and migration. The decision tree was tested on three exploration wells drilled in the Taranaki Basin, offshore New Zealand. Each segment’s key failure mode was identified based on the comprehensive, integrated evaluation of both pre- and postdrill reports, seismic data, well logs, geochemical analysis of gases and source rocks, and other materials freely available through the New Zealand government.
    [Show full text]
  • Southwest Pacific Absolute Plate Kinematic Reconstruction Reveals
    Tectonics RESEARCH ARTICLE Southwest Pacific Absolute Plate Kinematic 10.1029/2017TC004901 Reconstruction Reveals Major Cenozoic Key Points: Tonga-Kermadec Slab Dragging • Tonga-Kermadec subduction zone is likely only ~30 Ma old Suzanna H. A. van de Lagemaat1 , Douwe J. J. van Hinsbergen1 , Lydian M. Boschman1 , • Northward Australian absolute plate 2 1,3 motion is illustrated by 1,500 km Peter J. J. Kamp , and Wim Spakman offset between South Loyalty Basin 1 2 slab and New Caledonian suture Department of Earth Sciences, Utrecht University, Utrecht, Netherlands, School of Science, University of Waikato, • Tonga-Kermadec slab was dragged Hamilton, New Zealand, 3Center for Earth Evolution and Dynamics (CEED), University of Oslo, Oslo, Norway 1,200 km northward through the mantle, alongside eastward rollback Abstract Tectonic plates subducting at trenches having strikes oblique to the absolute subducting plate fi “ Supporting Information: motion undergo trench-parallel slab motion through the mantle, recently de ned as a form of slab • Supporting Information S1 dragging.” We investigate here long-term slab-dragging components of the Tonga-Kermadec subduction • Data Set S1 system driven by absolute Pacific plate motion. To this end we develop a kinematic restoration of • Data Set S2 Tonga-Kermadec Trench motion placed in a mantle reference frame and compare it to tomographically Correspondence to: imaged slabs in the mantle. Estimating Tonga-Kermadec subduction initiation is challenging because S. H. A. van de Lagemaat and D. J. J. van another (New Caledonia) subduction zone existed during the Paleogene between the Australia and Pacific Hinsbergen, plates. We test partitioning of plate convergence across the Paleogene New Caledonia and Tonga-Kermadec [email protected]; [email protected] subduction zones against resulting mantle structure and show that most, if not all, Tonga-Kermadec subduction occurred after ca.
    [Show full text]