DOCSLIB.ORG

REPORT of the SEAFO SCIENTIFIC COMMITTEE 30 September

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
REPORT of the SEAFO SCIENTIFIC COMMITTEE 30 September 9th SEAFO Scientific Committee Meeting Report SEAFO SC Report 11/2013 SOUTH EAST ATLANTIC FISHERIES ORGANISATION (SEAFO) REPORT OF THE SEAFO SCIENTIFIC COMMITTEE 30 September – 11 October 2013 Scientific Committee of SEAFO The SEAFO Secretariat Strand Street no. 1 Swakopmund P.O. Box 4296 Walvis Bay, Namibia Phone: +264-64-406885 __________________________________ Facsimile: +264-64-406884 Chairperson: SEAFO Scientific Committee Email: [email protected] Mr. Paul Kainge Website: www.seafo.org [email protected] South East Atlantic Fisheries Organization [SEAFO] Page 1 of 65 9th SEAFO Scientific Committee Meeting Report SEAFO SC Report 11/2013 1 Opening of the meeting The 9th Annual Meeting of the SEAFO Scientific Committee (SC) was convened on 30 September to 11 October 2013 at the National Marine Institute Research Centre, NatMIRC, Swakopmund, Namibia. The Chairperson, Mr. Paul Kainge, opened the meeting and welcomed delegates. He emphasized that this will be an informal discussion of scientific issues and that all delegates are expected to freely express their scientific views so that issues can be resolved and the best possible advice be forwarded to the Commission. 2 Adoption of agenda and meeting arrangements SC adopted the provisional agenda with only minor revisions. Members were informed of practical arrangements for the meeting by the Executive Secretary. 1 Opening of the meeting ............................................................................................................................... 2 2 Adoption of agenda and meeting arrangements .......................................................................................... 2 3 Appointment of Rapporteur ......................................................................................................................... 3 4 Introduction of Observers ............................................................................................................................ 3 5 Introduction of Participants ......................................................................................................................... 3 6 Review of submitted SEAFO working documents and any related presentations, allocation to the agenda items. Working documents should be circulated by 16 September and presentations should be limited to a maximum duration of 10 minutes ............................................................................................ 4 7 Review of the report by the Executive Secretary presenting all landings, incidental by-catch and discard tables updated to include all available data to date ......................................................................... 5 8 Working Document by the SEAFO Data Manager presenting a detailed overview of SEAFO Database and procedures for collecting, updating and analysing the data. ............................................... 13 9 Review results of the Japanese 2013 exploratory fishing survey, and proposal for 2014 exploratory fishing survey. ........................................................................................................................................... 13 10 Draft Status Reports for commercially important species ......................................................................... 14 10.1 Patagonian toothfish (Dissostichus eleginoides) .............................................................................. 15 10.2 Alfonsino (Beryx splendens) ............................................................................................................ 16 10.3 Deep-sea red crab (Chaceon erytheiae) ............................................................................................ 16 10.4 Orange roughy (Hoplostethus atlanticus) ......................................................................................... 17 10.5 Southern boarfish/pelagic armourhead (Pseudopentaceros richardsoni). ........................................ 17 10.6 Helicolenus spp. ............................................................................................................................... 18 11 Review research activity in the SEAFO CA (Sep 2011-Aug 2013) ......................................................... 18 12 Review landings, spatial and temporal distribution of fishing activity and biological data on by-catch species. ...................................................................................................................................................... 19 13 Review the spatial distribution of reported catches of benthic organisms (coral, sponges etc.). .............. 29 14 Examine, where appropriate, assessments and research done by neighbouring organisations to SEAFO (e.g. BCC and CCAMLR). .......................................................................................................... 32 15 Review Total Allowable Catches and related management conditions for Patagonian toothfish, Deep- sea Red Crab and Southern boarfish/Pelagic armourhead for 2014/2015. ................................................ 33 Patagonian toothfish (Dissostichus eleginoides) ...................................................................................... 33 Deep-sea red crab (Chaceon erytheiae) .................................................................................................... 33 Southern boarfish/pelagic armourhead (Pseudopentaceros richardsoni). ................................................ 33 Helicolenus spp. ....................................................................................................................................... 33 South East Atlantic Fisheries Organization [SEAFO] Page 2 of 65 9th SEAFO Scientific Committee Meeting Report SEAFO SC Report 11/2013 16 Review of progress regarding development of an ID guide for fish, crustaceans and incidental by- catch species. ............................................................................................................................................. 33 17 Review progress made on Korean Observer workshop. ........................................................................... 34 18 Review progress regarding development of a SEAFO series of Working Documents and the numbering thereof. .................................................................................................................................... 35 19 Discuss the [1] Report of the South-Eastern Atlantic regional workshop to facilitate the description of ecologically or biologically significant marine areas and [2] the report of the FAO Regional Workshop on Vulnerable Marine Ecosystem (VMEs) in the SA Atlantic Ocean and the implications for SEAFO. ................................................................................................................................................ 35 20 Invitation for SEAFO to contribute to and participate in an FAO Project: “Demonstration and pilot implementation in ABNJ areas of management and conservation tools for deep-sea fisheries, and conservation and sustainable use of VMEs and EBSAs. .......................................................................... 35 21 Feedback by Database Manager on the CWP/FIRMS meetings. .............................................................. 36 22 Review specific rules and guidelines for biological data sampling (e.g. maturity, sample size, weight and length frequency). ............................................................................................................................... 36 23 Advice and recommendations to the Commission on issues emanating from the meeting. ..................... 37 24 Future work program for the SC. .............................................................................................................. 38 25 Any other matters. ..................................................................................................................................... 39 26 Budget for 2014. ........................................................................................................................................ 39 27 Adoption of the report. .............................................................................................................................. 39 28 Date and place of the next meeting. .......................................................................................................... 39 29 Closure of the meeting. ............................................................................................................................. 39 30 References ................................................................................................................................................. 39 APPENDIX I – List of Participants .......................................................................................................... 40 APPENDIX II – Complete structure of the new SEAFO Observer Database ......................................... 42 APPENDIX III – 2013 Report on Japanese Exploratory Fishing in Division D0 ................................... 43 APPENDIX IV – Exploratory Fishing Proposal for 2014 ....................................................................... 57 APPENDIX V – SC Matrix of the FAO-ABNJ Project ........................................................................... 62 3 Appointment of Rapporteur After nomination and secondment, Mr. Erich Maletzky was appointed as rapporteur for the Scientific Committee meeting. 4 Introduction of Observers Observers
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]
  • Shona and Discovery Seamount Chains
    Goldschmidt Conference Abstracts 2009 A229 Shona and Discovery seamount Uranium-lead dating of speleothems: chains, South Atlantic: Prospects and limitations Superplume source constraints R.A. CLIFF 1 2 C. CLASS * AND A.P. LE ROEX School of Earth & Environment, University of Leeds 1Lamont-Doherty Earth Observatory of Columbia University, In recent year several studies have shown that U-Pb Palisades, NY 10964, USA isotopic dating is a promising option for dating speleothems (*correspondence: [email protected]) from the early Pleistocene and earlier which has otherwise 2University of Cape Town, Rondebosch 7701, South Africa presented a difficult challenge. ([email protected]) The integrity of the U-Pb system has been confirmed by comparison of U-Pb and U-Th data on a speleothem from the The effectively un-sampled major bathymetric anomalies Spannagel Cave in the Austrian Alps. Disequilibrium- of the Shona Ridge – Meteor Rise – Agulhas Ridge – Cape corrected U-Pb ages date growth from 340 ka to 267 ka. High Rise and Discovery seamounts in the South Atlantic have been resolution sampling of one short growth interval yielded U-Pb attributed to the activity of the Shona and Discovery mantle and U-Th ages in close agreement at 266 ka with ± 1 ka error plumes based solely on geochemical signatures measured in on the U-Pb age. These results confirm closed system Mid-Ocean Ridge basalts from the adjacent Mid-Atlantic behaviour throughout the uranium decay chain even in such Ridge and a single Discovery Seamount sample. Here we U-rich samples. present new Sr-Nd-Pb-Hf isotope data on dredge samples Speleothems from the Wilder Mann and Wildmahd caves from these seamount chains collected by the ANT XXIII/5 in the Allgäu Alps, western Austria encapsulate a detailed cruise of the FS Polarstern.
    [Show full text]
  • Insights Into the Origin and Evolution of Intraplate Magmatism in the Caribbean
    Insights into the origin and evolution of intraplate magmatism in the Caribbean (initial stage of the Galápagos hotspot) and the South Atlantic (Discovery and Shona hotspot tracks) DISSERTATION zur Erlangung des Doktorgrades der Mathematisch-Naturwissenschaftlichen Fakultät der Christian-Albrechts-Universität zu Kiel vorgelegt von Antje Dürkefälden Kiel, 2019 Erster Gutachter: ........................................................................................................Prof. Dr. Kaj Hoernle Zweiter Gutachter: .....................................................................................................Prof. Dr. Colin Devey Tag der mündlichen Prüfung: ..................................................................................................12.02.2019 Hiermit erkläre ich, dass die vorliegende Doktorarbeit, abgesehen von der Beratung durch den Betreuer, nach Inhalt und Form eine eigenständige und nur mit den angegebenen Hilfsmitteln verfasste Arbeit ist. Die Arbeit wurde noch nicht an einer anderen Stelle im Rahmen eines Prüfungsverfahrens vorgelegt, veröffentlicht oder zur Veröffentlichung eingereicht. Ferner versichere ich, dass die Arbeit unter Einhaltung der Regeln guter wissenschaftlicher Praxis der Deutschen Forschungsgemeinschaft entstanden ist. Es wurde kein akademischer Grad entzogen. Kiel, den ................................................................................................................................... AntJe Dürkefälden I Preface The following dissertation is composed of five independent
    [Show full text]
  • Report of SCUFN-11
    Distribution : limited IOC-IHO/GEBCO SCUFN-XI/3 English only Rev. 1, July 1995 INTERGOVERNMENTAL INTERNATIONAL OCEANOGRAPHIC HYDROGRAPHIC COMMISSION (of UNESCO) ORGANIZATION Eleventh Meeting of the GEBCO Sub-Committee on Undersea Feature Names (SCUM International Hydrographic Bureau Monaco, 11-13 May 1995 SUMMARY REPORT IOC-IHO/GEBCO-SCUFN-XI/3 Page i ALPHABETIC INDEX OF UNDERSEA FEATURE NAMES APPEARING IN THIS REPORT NAME Page NAME Page ALBUQUERQUE (Cayos de) 18 AUBERT DE LA RUE 10 Seamounts ALBUQUERQUE Valley 18 AUCKLANDS Escarpment 36 ALBUQUERQUE Spur 18 AWATEA Seamount 38 ALCOCK Rise 7 AXTHELM Seamount 37 ALICE Gap 14 BACATA Plateau 20 ALICE Shoal 13, 14 BACHUE Valley 20 ALICIA Gap 14 BALLENY Seamounts 37 ALICIA Shoal 13 BAO CHUAN Fracture Zone 2 ALICIA Spur 14 BARSUKOV Seamount 34 ALLEN Guyot 28 BARTLETT Seamounts 29 AMBALENA Gap 15 BATHYMETRISTS Seamounts 22 AMBALENA Valley 15 BENGAL Fan 10 ANTIOPE Reef 39 BERKNER Bank 4 ARACATACA Hill 17 BEVERIDGE Reef 39 ARAFURA Seachannel 24 BLAKE Canyon 4 ARAFURA Shelf 24 BLAKE Escarpment 4 ARAGO (Mont) 12 BLAKE Spur 4 ARAGO Reef 12 BOCHITA Basin 20 ARAGO Seamount 12 BOUNTY Seachannel 39 ARAWAC Hill 15 BOUSSOLE Seamount 26 ARAWAC Spur 16 BRANSFIELD Trough 4 ARGONAUT Seamount 25 CALARCA Pinnacle 17 ARJONA Spur 18 CALARCA Reef 17, 19 ARKHANGELSKY Ridge 23 CALIMA Seamount 16 ARU Seachannel 24 CAMPBELL Escarpment 36 ARUZI Hill 13 CAP HORN Seamount 8 ATLANTIC-INDIAN Basin 4 CAREX Valley 19 IOC-IHO/GEBCO-SCUFN-XI/3 Page ii NAME Page NAME Page CARRON Seamount 22 ELLSWORTH Bank 37 CARTER Seamount 32
    [Show full text]
  • Thirteenth Meeting of the GEBCO Sub-Committee on Undersea Feature Names (SCUFN)
    Distribution : limited IOC-IHO/GEBCO SCUFN-XIII/3 English only INTERGOVERNMENTAL INTERNATIONAL OCEANOGRAPHIC HYDROGRAPHIC COMMISSION (of UNESCO) ORGANIZATION Thirteenth Meeting of the GEBCO Sub-Committee on Undersea Feature Names (SCUFN) Halifax, Nova Scotia, Canada 22-25 June 1999 SUMMARY REPORT IOC-IHO/GEBCO SCUFN-XIII/3 Page intentionally left blank IOC-IHO/GEBCO SCUFN-XIII/3 Page i ALPHABETIC INDEX OF UNDERSEA FEATURE NAMES CONSIDERED AT SCUFN XIII AND APPEARING IN THIS REPORT (*=new name approved) Name Page ABROLHOS Shelf (Bank) Annex 5 AKADEMIK KURCHATOV Fracture Zone * 39 ALBACORA Caldera * 13 ALBUFEIRA, Planalto de 14 ALBUQUERQUE, Planalto de 14 ALMEIDA CARVALHO Seamounts * 14 ALMEIDA, Vale de 14 ALMIRANTE SALDANHA Guyot (Seamount) Annex 5 ALVARES CABRAL Seachannel * 14 AMAZON Canyon (Canyons) Annex 5 AMAZON Cone (Fan) Annex 5 AMIRANTE Banks 52 AMIRANTE Trench 52 ANAXIMANDER Mountains 58 ANDREW Guyot 52 ANDROMEDA Seamount * 14 ANNAN Seamount 36 ANTIPODES Fracture Zone 48 ANTON BRUUN Rise 52 ANTON LEONOV Seamount 39 ARGO Fracture Zone 52 ARGUIN Bank * 34 ARGUIN Canyon * 34 AROSA Canyon * 15 ARRIFANA, Mar da 15 & 31 ASHTON Seamount 14 ASQUITH Rise 53 AURIGA Seamount * 15 AURORA Bank * 45 AVEIRO Valley * 15 BAGRATION Seamount 13 IOC-IHO/GEBCO SCUFN-XIII/3 Page ii BALDAQUE DA SILVA Passage * 15 BARDIN Seamount 53 BARONIE Mountains 58 BARRACOUTA Shoal 6 BARTOLOMEU DIAS Terrace * 14, 16 & 20 BASSETT-SMITH Shoal 6 BATHYMETRISTS Seamounts * 35 BEIRAL DE VIANA Escarpment * 16 BELLINGSHAUSEN Trough 11 BERKNER Bank 3 & 8 BERLENGA, Vale da
    [Show full text]
  • Tenth Meeting of the GEBCO Sub-Committee on Geographical Names and Nomenclature of Ocean Bottom Features
    Distribution : limited IOC-IHO/GEBCO SCGN-X/3 English only INTERGOVERNMENTAL INTERNATIONAL OCEANOGRAPHIC HYDROGRAPHIC COMMISSION (of UNESCO) ORGANIZATION Tenth Meeting of the GEBCO Sub-Committee on Geographical Names and Nomenclature of Ocean Bottom Features Scripps Institution of Oceanography La Jolla, California, USA, 29 April - 3 May 1993 SUMMARY REPORT 250-VI-1993 Page i IOC-IHO/GEBCO SCGN-X/3 ALPHABETICAL INDEX OF UNDERSEA FEATURE NAMES APPEARING IN THIS REPORT NAME Page NAME Page ADIEU Canyon 7 BROWN Reef 18 ADVENTURE Trough 26 CANOPUS Bank 20, 22 AGUILA Fracture Zone 23 CAPE RANGE Canyon 9 AGULHAS Ridge 19 CAPE RANGE Escarpment 9 ALBATROSS Bank 18 CARDNO Guyot 19 ALTHORPE Canyon 8 CARDNO Seamount 19 AMAZON Fan 19 CARNARVON Terrace 6 AMAZON Canyons 20 CARNARVON Canyon 9 AMAZONAS Cone 19 CARPATHIA Knoll 27 ANEGADA Ridge 3 CAT Gap 4 ATLANTIC-INDIAN Basin 28 CEARA Abyssal Plain 19 BAHAMA Basin 3 CEARA Ridge 19 BAHAMA Escarpment 3 CEDUNA Terrace 11 BARANOV Seamount 17 CEDUNA Canyon 7 BATIZA Guyot 23 CHAGOS Seamount 15 BELOUSOV Seamount 14, 20 CHARLOTTE Reef 27 BERKNER Bank 28 CIRCE Peak 13 BERYX Guyot 2 CLOATES Canyon 9 BIRMA Knoll 27 COLON Seamount 5 BLAKE Abyssal Plain 3 COLUMBUS Seamount 5 BLAKE Basin 3 CONCEPTION Seamount 23 BOUCHARD Seamount 23 CONGO Cone 19 BOUDEUSE Ridge 23 CONGO Fan 19 BOWERS Canyon 18 CUVIER Abyssal Plain 9 BRANSFIELD Trough 28 CUVIER Plateau 6 BROKEN Ridge 12 CUVIER (WALLABY) Plateau 10 BROKEN Plateau 12 CUVIER Escarpment 6 BROWN Bank 18 DANILEVSKIJ Seamount 15 DE COVILHAO Trough 14 Page ii IOC-IHO/GEBCO SCGN-X/3
    [Show full text]
  • Béguelin, Paul; Bizimis, Michael; Beier, Christoph; Turner, Simon
    Béguelin, Paul; Bizimis, Michael; Beier, Christoph; Turner, Simon; Rift–plume interaction reveals multiple generations of recycled oceanic crust in Azores lavas, Geochimica et Cosmochimica Acta, 2017 Koffman, Bess G; Dowd, Eleanor G; Osterberg, Erich C; Ferris, David G; Hartman, Laura H; Wheatley, Sarah D; Kurbatov, Andrei V; Wong, Gifford J; Markle, Bradley R; Dunbar, Nelia W; Rapid transport of ash and sulfate from the 2011 Puyehue‐Cordón Caulle (Chile) eruption to West Antarctica, Journal of Geophysical Research: Atmospheres, 2017 Zhang, Daohan; Audétat, Andreas; What Caused the Formation of the Giant Bingham Canyon Porphyry Cu-Mo-Au Deposit? Insights from Melt Inclusions and Magmatic Sulfides, Economic Geology 112 (2017) 221-244 Clift, Peter D; Zheng, Hongbo; Carter, Andrew; Böning, Philipp; Jonell, Tara N; Schorr, Hannah; Shan, Xin; Pahnke, Katharina; Wei, Xiaochun; Rittenour, Tammy; Controls on erosion in the western Tarim Basin: Implications for the uplift of northwest Tibet and the Pamir, Geosphere 13 (2017) 1-9 Zhong, Yun; Liu, Wei-Liang; Xia, Bin; Liu, Jing-Nan; Guan, Yao; Yin, Zhen-Xing; Huang, Qiang-Tai; Geochemistry and geochronology of the Mesozoic Lanong ophiolitic mélange, northern Tibet: Implications for petrogenesis and tectonic evolution, Lithos 2017 Jang, Kwangchul; Huh, Youngsook; Han, Yeongcheol; Authigenic Nd isotope record of North Pacific Intermediate Water formation and boundary exchange on the Bering Slope, Quaternary Science Reviews 156 (2017) 150-163 Olierook, Hugo KH; Merle, Renaud E; Jourdan, Fred; Toward
    [Show full text]
  • South Atlantic Paleobathymetry Since Early Cretaceous Lucía Pérez-Díaz 1 & Graeme Eagles2
    www.nature.com/scientificreports OPEN South Atlantic paleobathymetry since early Cretaceous Lucía Pérez-Díaz 1 & Graeme Eagles2 We present early Cretaceous to present paleobathymetric reconstructions and quantitative uncertainty Received: 14 October 2016 estimates for the South Atlantic, ofering a strong basis for studies of paleocirculation, paleoclimate Accepted: 1 September 2017 and paleobiogeography. Circulation in an initially salty and anoxic ocean, restricted by the topography Published: xx xx xxxx of the Falkland Plateau, Rio Grande Ridge and Walvis Rise, favoured deposition of thick evaporites in shallow water of the Brazilian-Angolan margins. This ceased as seafoor spreading propagated northwards, opening an equatorial gateway to shallow and intermediate circulation. This gateway, together with subsiding volcano-tectonic barriers would have played a key role in Late Cretaceous climate changes. Later deepening and widening of the South Atlantic, together with gateway opening at Drake Passage would lead, by mid-Miocene (∼15 Ma) to the establishment of modern-style thermohaline circulation. A recent study1 suggests that the main control over ocean dynamics and, with it, paleoclimate and foral and fau- nal evolution, is imposed by changes in paleogeography. Tese controls are exerted in various ways, for example by the opening or closure of oceanic gateways or the uplif and subsidence of submarine ridges and plateaus. Reliable bathymetric models are thus important as datasets and boundary conditions for considerations of pale- oceanography and paleoclimate. Te South Atlantic ocean, with its long history of growth, diverse topography of tectonic and magmatic ridges and plateaus, long continental margins, northern and southern gateways and extreme variations in sediment thickness, is a case in point.
    [Show full text]
  • SCUFN-XVII English Only
    Distribution : limited IOC-IHO/GEBCO SCUFN-XVII English only INTERGOVERNMENTAL INTERNATIONAL OCEANOGRAPHIC HYDROGRAPHIC COMMISSION (of UNESCO) ORGANIZATION The Head Department of Navigation and Oceanography (HDNO) of the Russian Federation Ministry of Defense St. Petersburg, Russia 8-11 June 2004 SUMMARY REPORT IOC-IHO/GEBCO SCUFN-XVII Page 2 Page intentionally left blank IOC-IHO/GEBCO SCUFN-XVII Page 3 Notes: A list of actions arising from this meeting is in Annex 3. A list of acronyms, used in this report, is in Annex 4. An alphabetical index of all undersea feature names appearing in this report is in Annex 5. 1. INTRODUCTION – APPROVAL OF AGENDA The seventeenth meeting of the GEBCO Sub-Committee on Undersea Feature Names (SCUFN) met at The Head Department of Navigation and Oceanography (HDNO) of the Russian Federation of Defense in St. Petersburg, Russia under the Chairmanship of Dr. Hans Werner Schenke, Alfred Wegener Institute (AWI), Germany. Dr. Schenke opened the meeting by thanking the HDNO for their hospitality and expressing his appreciation for the beauty of St. Petersburg during the ‘white nights’. Admiral Anatoliy A. Komaritsyn, Head Department of Navigation and Oceanography of the Russian Federation welcomed the meeting participants and gave a brief history of Russian ocean exploration. Attendees included SCUFN members Dr. Galina V. Agapova (Geological Institute of the Russian Academy of Sciences, Russia), Ing. en chef Michel Huet, secretary (IHB, Monaco), Ms. Lisa A. Taylor (NGDC, USA), Captain Vadim Sobolev (HDNO, Russian Federation), Mr. Norman Z. Cherkis (Five Oceans Consultants, USA) and Dr. Yasuhiko Ohara (Hydrographic and Oceanographic Department of Japan) as an unofficial new member.
    [Show full text]
  • Becker, T. W., & Advance Our Understanding of Deep Mantle Reservoir Distributions, and We Discuss How Continental and Steinberger, B
    RESEARCH ARTICLE Spatial Characteristics of Recycled and Primordial 10.1029/2020GC009525 Reservoirs in the Deep Mantle Key Points: M. G. Jackson1 , T. W. Becker2 , and B. Steinberger3,4 • High-3He/4He signatures at hotspots are not confined to the Large Low 1Department of Earth Science, University of California, Santa Barbara, Santa Barbara, CA, USA, 2Department of Shear Wave Velocity Provinces 3 4 Geological Sciences, Institute for Geophysics, Jackson School of Geosciences, The University of Texas at Austin, Austin, (LLSVPs), because the high- He/ He 3 Yellowstone hotspot is not linked to TX, USA, Section 2.5 Geodynamic Modelling, GFZ German Research Centre for Geosciences, Potsdam, Germany, the LLSVPs 4Centre for Earth Evolution and Dynamics, University of Oslo, Oslo, Norway • Plume dynamics (i.e., buoyancy), not geography, determines whether a deep, dense, and possibly widespread 3 4 Abstract The spatial distribution of the geochemical domains hosting recycled crust and primordial high- He/ He domain is entrained 3 4 • Plume-fed EM (enriched mantle) (high- He/ He) reservoirs, and how they are linked to mantle convection, are poorly understood. Two hotspots are associated with the continent-sized seismic anomalies located near the core-mantle boundary—called the Large Low Shear southern regions of both LLSVPs; Wave Velocity Provinces (LLSVPs)—are potential geochemical reservoir hosts. It has been suggested that HIMU hotspots are not linked to the 3 4 LLSVPs high- He/ He hotspots are spatially confined to the LLSVPs, hotspots sampling recycled continental crust are associated with only one of the LLSVPs, and recycled continental crust shows no relationship with latitude. We reevaluate the links between LLSVPs and isotopic signatures of hotspot lavas using improved Supporting Information: mantle flow models including plume conduit advection.
    [Show full text]
  • 1 Plate Velocities in Hotspot Reference Frame
    1 Plate velocities in hotspot reference frame: electronic supplement W. Jason Morgan Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Jason Phipps Morgan Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, New York 14853, USA ABSTRACT We have made a table of 57 hotspots, giving the track azimuths of their present motions and track rates where there was age control. This electronic supplement (with 301 references) gives the supporting data for each entry in this table and has a discussion of the probable errors in azimuth/rate for each entry. It also contains a discussion of ‘hotspot-like-features’ considered not to show plate motion and omitted from the table. INTRODUCTION An important column in Table 1 is the weight ‘w’, a number between 1 and 0.2. It is our estimate of the accuracy of the azimuth of the track of a hotspot. The angular difference between the observed azimuth and modeled azimuth is multiplied by this weight when making the measure of goodness of fit that we minimize to solve for best-fit. The weight w has no meaning in regards to rate, only the rate error bars indicate that. The weight is based on the estimated error of the azimuth of the track (σazim), with 2 downward adjustment of the weight at some tracks based on qualitative criteria (e.g., influence of a nearby fracture zone). The general rule for assigning weight is: (σazim≤8°) ⇒ w=1.0 (8°<σazim≤10°) ⇒ w=0.8 (10°<σazim≤12°) ⇒ w=0.5 (12°<σazim≤15°) ⇒ w=0.3 (15°<σazim) ⇒ w=0.2.
    [Show full text]
  • The Crustal Structure of Walvis Ridge at 6° E
    Tectonophysics 716 (2017) 108–120 Contents lists available at ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto Interaction between a hotspot and a fracture zone: The crustal structure of Walvis Ridge at 6◦ E Tanja Fromm a,*, Wilfried Jokata, Jan H. Behrmann b aAlfred-Wegener-Institut für Polar- und Meeresforschung, Am Alten Hafen 26, Bremerhaven D-27568, Germany bGEOMAR, Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel D-24148, Germany ARTICLE INFO ABSTRACT Article history: The Walvis Ridge is one of the major hotspot trails in the South Atlantic and a classical example for volcanic Received 1 February 2016 island chains. Two models compete about the origin of the ridge: It is either the result of a deep mantle Received in revised form 2 March 2017 plume or active fracture zones above mantle inhomogeneities. Among other things crustal information is Accepted 3 March 2017 needed to constrain the models. Here, we provide such constraint with a 480 km long P-wave velocity model Available online 8 March 2017 of the deep crustal structure of the eastern Walvis Ridge at 6◦ E. According to our data the Walvis Ridge stretches across the Florianopolis Fracture Zone into the Angola Basin. Here, we observe a basement high Keywords: and thick basaltic layers covering the oceanic crust and the fracture zone. We found two crustal roots along Refraction seismic the profile: one is located beneath the ridge crest, the other one beneath the northern basement high in the Crustal structure Hotspot Angola Basin. The crustal thickness reaches 18 km and 12 km and the lower crustal velocities are 7.2 km/s South Atlantic Opening and 7.4 km/s, respectively.
    [Show full text]