Chapter 2 Regional Tectonic Context
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Program and Abstracts
The Atlantic Geoscience Society (AGS) La Société Géoscientifique de l’Atlantique 45th Colloquium and Annual Meeting Special Sessions: • Special Session: In Memory of Dr. Trevor MacHattie (1974 - 2018) • Paleontology and Sedimentology in Atlantic Canada: In Memory of Dr. Ron Pickerill (1947 – 2018) • Current Research in Carboniferous Geology in the Atlantic Provinces • Minerals, metals, melts, and fluids associated with granitoid rocks: new insights from fundamental studies into the genesis, melt fertility, and ore-forming processes • Earth Science Outreach in the Maritime Provinces • Geohazards: Recent and Historical General Sessions: Current Research in the Atlantic Provinces February 7-9, 2019 Fredericton Inn, Fredericton, New Brunswick PROGRAM WITH ABSTRACTS We gratefully acknowledge sponsorship from the following companies and organizations: Department of Energy and Resource Development Geological Surveys Branch Department of Energy and Mines Department of Energy and Mines Geological Surveys Division Petroleum Resources Division Welcome to the 45th Colloquium and Annual Meeting of the Atlantic Geoscience Society in Fredericton, New Brunswick. This is a familiar place for AGS, having been a host several times over the years. We hope you will find something to interest you and generate discussion with old friends and new. AGS members are clearly pushing the boundaries of geoscience in all its branches! Be sure to take in the science on the posters and the displays from sponsors, and don’t miss the after-banquet jam and open mike on Saturday night. For social media types, please consider sharing updates on Facebook and Twitter (details in the program). We hope you will be able to use the weekend to renew old acquaintances, make new ones, and further the aims of your Atlantic Geoscience Society. -
Connecting the Deep Earth and the Atmosphere
In Mantle Convection and Surface Expression (Cottaar, S. et al., eds.) AGU Monograph 2020 (in press) Connecting the Deep Earth and the Atmosphere Trond H. Torsvik1,2, Henrik H. Svensen1, Bernhard Steinberger3,1, Dana L. Royer4, Dougal A. Jerram1,5,6, Morgan T. Jones1 & Mathew Domeier1 1Centre for Earth Evolution and Dynamics (CEED), University of Oslo, 0315 Oslo, Norway; 2School of Geosciences, University of Witwatersrand, Johannesburg 2050, South Africa; 3Helmholtz Centre Potsdam, GFZ, Telegrafenberg, 14473 Potsdam, Germany; 4Department of Earth and Environmental Sciences, Wesleyan University, Middletown, Connecticut 06459, USA; 5DougalEARTH Ltd.1, Solihull, UK; 6Visiting Fellow, Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia. Abstract Most hotspots, kimberlites, and large igneous provinces (LIPs) are sourced by plumes that rise from the margins of two large low shear-wave velocity provinces in the lowermost mantle. These thermochemical provinces have likely been quasi-stable for hundreds of millions, perhaps billions of years, and plume heads rise through the mantle in about 30 Myr or less. LIPs provide a direct link between the deep Earth and the atmosphere but environmental consequences depend on both their volumes and the composition of the crustal rocks they are emplaced through. LIP activity can alter the plate tectonic setting by creating and modifying plate boundaries and hence changing the paleogeography and its long-term forcing on climate. Extensive blankets of LIP-lava on the Earth’s surface can also enhance silicate weathering and potentially lead to CO2 drawdown (cooling), but we find no clear relationship between LIPs and post-emplacement variation in atmospheric CO2 proxies on very long (>10 Myrs) time- scales. -
Aula 4 – Tipos Crustais Tipos Crustais Continentais E Oceânicos
14/09/2020 Aula 4 – Tipos Crustais Introdução Crosta e Litosfera, Astenosfera Crosta Oceânica e Tipos crustais oceânicos Crosta Continental e Tipos crustais continentais Tipos crustais Continentais e Oceânicos A interação divergente é o berço fundamental da litosfera oceânica: não forma cadeias de montanhas, mas forma a cadeia desenhada pela crista meso- oceânica por mais de 60.000km lineares do interior dos oceanos. A interação convergente leva inicialmente à formação dos arcos vulcânicos e magmáticos (que é praticamente o berço da litosfera continental) e posteriormente à colisão (que é praticamente o fechamento do Ciclo de Wilson, o desparecimento da litosfera oceânica). 1 14/09/2020 Curva hipsométrica da terra A área de superfície total da terra (A) é de 510 × 106 km2. Mostra a elevação em função da área cumulativa: 29% da superfície terrestre encontra-se acima do nível do mar; os mais profundos oceanos e montanhas mais altas uma pequena fração da A. A > parte das regiões de plataforma continental coincide com margens passivas, constituídas por crosta continental estirada. Brito Neves, 1995. Tipos crustais circunstâncias geométrico-estruturais da face da Terra (continentais ou oceânicos); Característica: transitoriedade passar do Tempo Geológico e como forma de dissipar o calor do interior da Terra. Todo tipo crustal adveio de um outro ou de dois outros, e será transformado em outro ou outros com o tempo, toda esta dança expressando a perda de calor do interior para o exterior da Terra. Nenhum tipo crustal é eterno; mais "duráveis" (e.g. velhos Crátons de de "ultra-longa duração"); tipos de curta duração, muitas modificações e rápida evolução potencial (como as bacias de antearco). -
The Western North Atlantic Region
THE WESTERN NORTH ATLANTIC REGION The Geology of North America Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/4149319/9780813754642_frontmatter.pdf by guest on 02 October 2021 Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/4149319/9780813754642_frontmatter.pdf by guest on 02 October 2021 The Western North Atlantic Region Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/4149319/9780813754642_frontmatter.pdf by guest on 02 October 2021 Frontispiece 1. Examples of principal lithofacies in the western North Atlantic Ocean basin. All are core samples from the Deep Sea Drilling Project. Each is identified in parentheses below according to cruise leg, site number (with hole number, A., B., etc., if applicable), core number, core-section number, and depth interval in core section (in centimeters). 1. Un-named formation, Blake-Bahama Basin. Upper Callovian to lower Oxfordian dark claystone with coarser radiolarian siltstone lenses, capped at top by lighter pelmicritic limestone that is graded and laminated (76, 534A, 120,1,48-65 cm). These and 63 m of underlying Callovian sedimen- tary rocks at Site 534A represent the oldest strata cored to date in the western North Atlantic basin. 2. Cat Gap Formation, lower continental rise off New Jersey. Upper Oxfordian to lower Kim- meridgian clayey limestone, well laminated to burrowed (11, 105, 37, 5, 82-113 cm). Colors which reflect the oxidation state of iron in the sediment (reddish = oxidized, grayish = reduced) are separated by diffuse boundaries. 3. Blake-Bahama Formation, lower continental rise off New Jersey. Upper Berriasian to lower Valanginian limestone and chalky limestone (11,105,28,1,92-141 cm). -
Template for Submission of Scientific Information to Describe Areas Meeting Scientific Criteria for Ecologically Or Biologically Significant Marine Areas
Template for Submission of Scientific Information to Describe Areas Meeting Scientific Criteria for Ecologically or Biologically Significant Marine Areas Title/Name of the area: Canyons and Seamounts of the Northwest Atlantic Ocean within and beyond national jurisdiction Presented by: Lisa Speer, Director, International Oceans Program, Natural Resources Defense Council Peter Auster, Senior Research Scientist, Sea Research Foundation and Research Professor Emeritus, University of Connecticut. Introduction: Submarine canyons and seamounts off the Atlantic coast of the United States and Canada provide foraging, breeding, and/or nursery habitats for hundreds of fish and crustacean species, including swordfish, tuna, and sharks; marine mammals including endangered sperm whale, beaked whales, and dolphins; and isolated invertebrate communities including those dominated by deep sea corals and sponges. Location: Submarine canyons off the Atlantic coast of the United States and Canada occur mostly within the zones of national jurisdiction. Four of the New England Seamounts are within the jurisdiction of the United States. The remaining New England Seamounts and all of the Corner Rise Seamounts are located in ABNJ. See maps (links below). Feature description of the proposed area The varied seafloor topography and complex oceanographic influences of canyons and seamounts combine to create unique habitat for many species of corals, sponges and other invertebrates on the benthos and fish, marine mammals and birds in the pelagic realm. Deepwater canyons are a striking feature of the continental margin off the east coast of the United States and Canada. There are 15 major canyons in the United States alone, ranging in depth from about 200 meters to about 3,500 meters. -
Northward Drift of the Azores Plume in the Earth’S Mantle
ARTICLE https://doi.org/10.1038/s41467-019-11127-7 OPEN Northward drift of the Azores plume in the Earth’s mantle Maëlis Arnould 1,2,3, Jérôme Ganne4, Nicolas Coltice1 & Xiaojun Feng 5 Mantle plume fixity has long been a cornerstone assumption to reconstruct past tectonic plate motions. However, precise geochronological and paleomagnetic data along Pacific continuous hotspot tracks have revealed substantial drift of the Hawaiian plume. The 1234567890():,; question remains for evidence of drift for other mantle plumes. Here, we use plume-derived basalts from the Mid-Atlantic ridge to confirm that the upper-mantle thermal anomaly associated with the Azores plume is asymmetric, spreading over ~2,000 km southwards and ~600 km northwards. Using for the first time a 3D-spherical mantle convection where plumes, ridges and plates interact in a fully dynamic way, we suggest that the extent, shape and asymmetry of this anomaly is a consequence of the Azores plume moving northwards by 1–2 cm/yr during the past 85 Ma, independently from other Atlantic plumes. Our findings suggest redefining the Azores hotspot track and open the way for identifying how plumes drift within the mantle. 1 Laboratoire de Géologie, École Normale Supérieure, CNRS UMR 8538, PSL Research University, 75005 Paris, France. 2 Laboratoire de Géologie de Lyon, Terre, Planètes, Environnement, École Normale Supérieure de Lyon, Université de Lyon, Université Claude Bernard, CNRS UMR 5276, 2 rue Raphaël Dubois, 69622 Villeurbanne, France. 3 EarthByte Group, School of Geosciences, Madsen Building F09, University of Sydney, Sydney 2006 NSW, Australia. 4 IRD, CNRS, GET, Université Toulouse III, 14 Avenue Edouard Belin, 31400 Toulouse, France. -
SPOTLIGHT 4 New England and Corner Rise Seamounts
CORE Metadata, citation and similar papers at core.ac.uk or collective redistirbution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The approval Oceanography portionthe ofwith any articlepermitted only photocopy by is of machine, reposting, this means or collective or other redistirbution This article has This been published in Provided Mby WoodsOU HoleNT OpenAI AccessNS ServerIN THE Sea SPOTLIGHT 4 New England and Corner Rise Seamounts Oceanography By Timothy M. Shank , Volume 23, Number 1, a quarterly journal of The 23, NumberOceanography 1, a quarterly , Volume One of the longest seamount tracks in with ~ 75 morphotypes unique to the for understanding the changes in North the Atlantic Ocean was formed by the Corner Rise and ~ 60 unique to the Atlantic open-ocean circulation through Great Meteor or New England hotspot. New England Seamounts (Cho, 2008). time and the impact these changes have This more than 3000-km-long hotspot Interestingly, a variety of invertebrates on population connectivity. For example, track formed both the New England and are revealing differing levels of specificity corals in the northern North Atlantic Corner Rise seamounts, with a pause to their host corals, ranging from “facul- prospered during past interglacial in volcanism 83 million years ago as tative” to “obligate” (see Shank, 2010). periods and in particular throughout evidenced by the morphological gap For example, the galatheid Uroptychus the past 11,000 years, yet apparently between chains (Figure 1). The New has been observed only on the antipatha- disappeared during glacial times England and Corner Rise seamounts rian Parantipathes sp., and the ophiuroid (above 50°N). -
Page 1Of 12 OCEANOGRAPHY the ATLANTIC OCEAN by PROF
OCEANOGRAPHY THE ATLANTIC OCEAN BY PROF. A. BALSUBRAMANIAN Objectives 1.0 Introduction 1.1 One water body in the Globe 2.0 Geographic Setting of the Atlantic 2.1 Bordering regions of Atlantic 2.2 Areal Extent 2.3 Depth 2.4 Bays and Seas 2.5 Volume of water mass 3.0 Atlantic Ocean Explorations 3.1 Discovery of Trade routes 3.2 Beginning of Voyaging for Science 3.3 Modern Oceanographic Exploration 4.0 Crustal plates and the Atlantic 4.1 Widening Atlantic Ocean 5.0 Profile of the ocean floor 5.1 Continental shelf 5.2 Continental Slope 5.3 Submarine canyons 5.4 Deep ocean floor 5.5 Abyssal plains/hills 5.6 Features of Abyssal plains 6.0 Ocean basins 6.1 Mid ocean ridges 6.2 Notable Ridges 6.3 Rift valleys 6.4 Deep Ocean Trenches 6.5 Seamounts 6.6 Notable Seamounts of Atlantic 6.7 Guyots 6.8 Icebergs 7.0 Atlantic Coastal Plains 7.1 Islands or island arcs 8.0 Water masses and Temperature 8.1 Salinity 8.2 Density 8.3 Thermohaline circulation 9.0 Climate of the Atlantic 9.1 Effects on Climate 10.0 Ocean Currents 10.1 Notable Currents 11.0 Marine Life 12.0 Marine sediments 13.0 Natural Resources 13.1 Richest Fishing zones 13.2 Mineral resources 13.3 Diamond, Petroleum and Coal 13.4 Deep-Sea Minerals 14.0 Ports and harbours 15.0 Hazards 16.0 Conclusion. Page 1 of 12 GEOLOGY OCEANOGRAPHY THE ATLANTIC OCEAN Objectives After attending this lesson, the learner should be able to comprehend about the geographic setting of the Atlantic ocean, its dimension, associated water masses, morphological features of the ocean floor, very significant conditions of the ocean, sediments, marine life, marine pollution and other hazards. -
SPOTLIGHT 4 New England and Corner Rise Seamounts
or collective redistirbution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The approval Oceanography portionthe ofwith any articlepermitted only photocopy by is of machine, reposting, this means or collective or other redistirbution This article has This been published in MOUNTAINS IN THE Sea SPOTLIGHT 4 New England and Corner Rise Seamounts Oceanography By Timothy M. Shank , Volume 23, Number 1, a quarterly journal of The 23, NumberOceanography 1, a quarterly , Volume One of the longest seamount tracks in with ~ 75 morphotypes unique to the for understanding the changes in North the Atlantic Ocean was formed by the Corner Rise and ~ 60 unique to the Atlantic open-ocean circulation through Great Meteor or New England hotspot. New England Seamounts (Cho, 2008). time and the impact these changes have This more than 3000-km-long hotspot Interestingly, a variety of invertebrates on population connectivity. For example, track formed both the New England and are revealing differing levels of specificity corals in the northern North Atlantic Corner Rise seamounts, with a pause to their host corals, ranging from “facul- prospered during past interglacial in volcanism 83 million years ago as tative” to “obligate” (see Shank, 2010). periods and in particular throughout evidenced by the morphological gap For example, the galatheid Uroptychus the past 11,000 years, yet apparently between chains (Figure 1). The New has been observed only on the antipatha- disappeared during glacial times England and Corner Rise seamounts rian Parantipathes sp., and the ophiuroid (above 50°N). In contrast, corals in the S each have more than 35 and 50 major Ophiocreas oedipus only on the coral temperate North Atlantic were sustained ociety. -
Cretaceous Paleomagnetic Field in North America: True
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 97, NO. B13, PAGES 19,651-19,661, DECEMBER 10, 1992 Paleomagnetismof 122 Ma Plutonsin New England and the Mid-Cretaceous PaleornagneticField in North America' True Polar Wander or Large-Scale Differential Mantle Motion? MICKEY C. VAN FOSSEN AND DENNIS V. KENT Lamont-DohertyGeological Observatory and Departmentof GeologicalSciences, Columbia University, Palisades, iVew York A palcomagneticstudy of CretaceousWhite Mountainsplutonic complexes in New Hampshireand Vermont yields high unblockingtemperature, dual polarity magnetizationsin differenttypes of igneousrocks. The resultingpole position for threeplutons (71.9 ø N, 187.4ø E, A95 = 6.9ø, age= 122.5Ma) agreeswith pre- viously publishedmid-Cretaceous poles for North America, which togethergive a mid-Cretaceousstand- still referencepole slightlyrevised from Globermanand Irving [1988]at 71.2ø N, 194.1ø E (A95 = 3.7ø,N = 5 studies).We argueon the basisof the wide geographicdistribution of thesestudies, the varietyin tec- tonic settingsand rock types,positive reversal tests, and an overall reversalpattern consistent with geo- magneticpolarity time scales,that this mean pole representsthe North Americanmid-Cretaceous reference field for nominally 36 m.y. (124 to 88 Me). The standstillpole limits to within +4 ø, the motion of the North Americanplate relativeto the Earth'sspin axis. During the samemid-Cretaceous interval, the New Englandhotspot track (124 Ma MonteregianHills, 122.5-Ma CretaceousWhite Mountains,and 103- to 84-Me New Englandseamounts) requires 11ø't:4ø of nonh-polewardmotion of North America,in direct conflict with the palcomagneticstandstill. A similar (-13 ø) discrepancyis independentlydemonstrated betweenthe spin axis and the Tristan da Cunha hotspottrack on the African plate during the mid- Cretaceousinterval. •he hotspot/spinaxis discrepanciesended by -90 Ma when it is shownthat both Atlantic hotspotsagree with North Americanand African dipole palcolatitudesand present-daylocations. -
Ring-Shaped Morphological Features and Interpreted Small Seamounts Between Southern Quebec (Canada) and the New England Seamoun
Ring-shaped morphological features and interpreted small seamounts between southern Quebec (Canada) and the New England seamounts (USA) and their possible association with the New England hotspot track Ronald T. Marple1*, James D. Hurd2, and Robert J. Altamura3 1. 1516 Loblolly Drive, Harker Heights, Texas 76548, USA 2. Department of Natural Resources and the Environment, The University of Connecticut U-87, Room 308, 1376 Storrs Road, Storrs, Connecticut 06269-4087, USA 3. Consulting Geologist, 1601 Yardal Road, State College, Pennsylvania 16801-6966, USA *Corresponding author <[email protected]> Date received: 20 April 2018 ¶ Date accepted: 27 May 2018 ABSTRACT Enhancements of recently available high-resolution multibeam echosounder data from the western Gulf of Maine and Atlantic continental margin and light detection and ranging (LiDAR) and digital elevation model data from southeastern Quebec (Canada) and the northeastern United States have revealed numerous ring-shaped morphological features and interpreted small seamounts between the Monteregian Hills igneous province and the New England seamounts. The morphological features onshore are mainly ring-shaped depressions, several of which surround mapped igneous intrusions in the Monteregian Hills igneous province and White Mountain magma series. Most of the rings offshore are also depressions, although a few rings are curved ridges above the seafloor. The largest ring in the western Gulf of Maine is the 30-km-diameter Tillies ring that lies 20 km east of Cape Ann, MA. Several small (<3 km in diameter) round, flat-topped submerged hills that we interpret to be volcanic necks are also present beneath the western Gulf of Maine. The rings between Cape Cod and the continental slope are more subtle because of thicker sediments and poorer spatial resolution of the sonar data in this area. -
For Shame...It's So Quétaine
For Shame...it's so Quétaine Tonight – June 1, 2018 – I wept while traversing my "Mont Royal" At a crawl to savour my "last" permitted through passage A lassitude, a heaviness descended upon my psyche The rule oF the bicycle has arrived, I cried, in frustration and despair The lies and the halF truths that are being propagated The emotions that are being manipulated, Truth is being down-rated, strangulated, mutilated The city I love is being divided by those whose vision is diFFerent than mine It's a crime, in my eyes at least, East and west pitted against one another, I feel depleted, cheated, deFeated, robbed oF a way across the soul oF my island home Their goal in part...the dominance oF the cyclist The demoralization oF the motorist. I groan in absolute Frustration, especially when I see, right there in Front oF me... An ugly barricade, blocking a beloved scene I had come to view...boo hoo to A towering set of ugly wooden bleachers, planks and nuts and bolts and rusty steel, A real and crude monstrosity, given you see The undoubtedly and unwittingly ironic nomenclature oF "Belvédère Soleil". Pray it's only temporary...because it's all so very visibly, risibly "quétaine" For shame, blocking a view oF beauty by such a shoddy, ticky-tacky viewing platForm, By what norm of architectural design can that be viewed as an improvement to Our wonderFul sky-high island park? No earthly spark, no vision oF Olmstead, So oFt referred to in the City's propaganda, Could have included a monstrosity such as this Tsk tsk! What is it supposed to tempt a pedestrian mountain population to do? Clamber high up it, iF you're able..