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Canada's Active Western Margin
Geoscience Canada. Volume 3. Nunber 4 269 in the area of Washington and Oregon seemed necessary geometrically. This suggestion was reiterated by Tobin and Sykes (1968) in their study of the seismicity ofthe regionanddevelopedin established the presence and basic bathymetric trench at the foot of the Canada's Active configuration of an active spreading continental slope, the absence of a ocean ridge system ofl the west coast of clearly defined eastward dipping Beniofl Western Margin - Vancwver Island. The theory of the earthquake zone and the apparently geometrical mwement of rigid quiescent state of present volcanism The Case for lithospheric plates on a spherical earth have all contributed toward a (introducedas the 'paving stone' theory) widespreaa uncertalnfy as to whether Subduction was tirst ~ro~osedand tasted bv subddctlon 1s cbrrently taking place ~c~enziiand Parker (1967) using data (e.8.. Crosson. 1972: ~rivast&a,1973; R. P. Riddihough and R. D. Hyndnan from the N. Pacific and in the global Stacey. 1973). Past subduction, fran Victoria Geophysical Observatory, extension of the theory by Morgan several tens of m.y. ago until at leastone Earth Physics Branch, (1 968) this reglon again played a major or two m y. ago. IS more generally Department Energy, Mines and role Morgan alsoconcluded that a small accepted ana it seems to us that the Resources, block eitof theJuandeFuca ridge (the case for contemporary subduction, in a 5071 W. Saanich Rd. Juan de Fuca plate. Fig. 2) was moving large part, must beargued upona Victoria B. C. independently of the main Pacific plate. continuation into the present of the The possibility that theJuan de Fuca processes shown to be active in the Summary plate is now underthrustingNorth recent geological past. -
Washington Division of Geology and Earth Resources Open File Report
l 122 EARTHQUAKES AND SEISMOLOGY - LEGAL ASPECTS OPEN FILE REPORT 92-2 EARTHQUAKES AND Ludwin, R. S.; Malone, S. D.; Crosson, R. EARTHQUAKES AND SEISMOLOGY - LEGAL S.; Qamar, A. I., 1991, Washington SEISMOLOGY - 1946 EVENT ASPECTS eanhquak:es, 1985. Clague, J. J., 1989, Research on eanh- Ludwin, R. S.; Qamar, A. I., 1991, Reeval Perkins, J. B.; Moy, Kenneth, 1989, Llabil quak:e-induced ground failures in south uation of the 19th century Washington ity of local government for earthquake western British Columbia [abstract). and Oregon eanhquake catalog using hazards and losses-A guide to the law Evans, S. G., 1989, The 1946 Mount Colo original accounts-The moderate sized and its impacts in the States of Califor nel Foster rock avalanches and auoci earthquake of May l, 1882 [abstract). nia, Alaska, Utah, and Washington; ated displacement wave, Vancouver Is Final repon. Maley, Richard, 1986, Strong motion accel land, British Columbia. erograph stations in Oregon and Wash Hasegawa, H. S.; Rogers, G. C., 1978, EARTHQUAKES AND ington (April 1986). Appendix C Quantification of the magnitude 7.3, SEISMOLOGY - NETWORKS Malone, S. D., 1991, The HAWK seismic British Columbia earthquake of June 23, AND CATALOGS data acquisition and analysis system 1946. [abstract). Berg, J. W., Jr.; Baker, C. D., 1963, Oregon Hodgson, E. A., 1946, British Columbia eanhquak:es, 1841 through 1958 [ab Milne, W. G., 1953, Seismological investi earthquake, June 23, 1946. gations in British Columbia (abstract). stract). Hodgson, J. H.; Milne, W. G., 1951, Direc Chan, W.W., 1988, Network and array anal Munro, P. S.; Halliday, R. J.; Shannon, W. -
Geology, Geochemistry and Earthquake History of Loieihi Seamount, Hawaiei's Youngest Volcano
ARTICLE IN PRESS Chemie der Erde ] (]]]]) ]]]–]]] www.elsevier.de/chemer INVITED REVIEW Geology, geochemistry and earthquake history of Lo¯"ihi Seamount, Hawai"i’s youngest volcano Michael O. Garciaa,Ã, Jackie Caplan-Auerbachb, Eric H. De Carloc, M.D. Kurzd, N. Beckera aDepartment of Geology and Geophysics, University of Hawai"i, Honolulu, HI 96822, USA bAlaska Volcano Observatory, U.S.G.S., Alaska Science Center, Anchorage, AK 99508, USA cDepartment of Oceanography, University of Hawai"i, Honolulu, HI 96822, USA dDepartment of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA Received 6 June 2005; accepted 20 September 2005 Abstract A half-century of investigations are summarized here on the youngest Hawaiian volcano, Lo¯"ihi Seamount. It was discovered in 1952 following an earthquake swarm. Surveying in 1954 determined it has an elongate shape, which is the meaning of its Hawaiian name. Lo¯"ihi was mostly forgotten until two earthquake swarms in the 1970s led to a dredging expedition in 1978, which recovered young lavas. The recovery of young lavas motivated numerous expeditions to investigate the geology, geophysics, and geochemistry of this active volcano. Geophysical monitoring, including a real- time submarine observatory that continuously monitored Lo¯"ihi’s seismic activity for 3 months, captured some of the volcano’s earthquake swarms. The 1996 swarm, the largest recorded in Hawai"i, was preceded earlier in the year by at least one eruption and accompanied by the formation of a 300-m deep pit crater, Pele’s Pit. Seismic and petrologic data indicate that magma was stored in a 8–9 km deep reservoir prior to the 1996 eruption. -
Posteruption Enhancement of Hydrothermal Activity: a 33-Year, Multieruption Time Series at Axial Seamount (Juan De Fuca Ridge)
RESEARCH ARTICLE Posteruption Enhancement of Hydrothermal Activity: A 10.1029/2018GC007802 33‐Year, Multieruption Time Series at Axial Key Points: • Water column surveys, 1985‐2017, Seamount (Juan de Fuca Ridge) show that hydrothermal plume rise Edward T. Baker1,2 , Sharon L. Walker2 , William W. Chadwick Jr3 , height and turbidity identify the last 1,2 1,2 1,2 three Axial Seamount eruptions David A. Butterfield , Nathaniel J. Buck , and Joseph A. Resing • Posteruptive enhancement of 1 2 hydrothermal activity lasted 2‐5 Joint Institution for the Study of the Atmosphere and Ocean, University of Washington, Seattle, WA, USA, NOAA/ years posteruption, totaling Pacific Marine Environmental Laboratory, Seattle, WA, USA, 3NOAA Pacific Marine Environmental Laboratory, ~10 years over the survey duration Newport, OR, USA • Posteruption heat flux increased sixfold, implying that fluxes based on noneruptive activity alone will ‐ underestimate the long‐term flux Abstract Mid ocean ridge eruptions, initiating or revitalizing hydrothermal discharge and disrupting seafloor ecosystems, occur regularly as a consequence of plate spreading. Evaluating their impact on Supporting Information: long‐term hydrothermal discharge requires information on the scale and duration of any posteruption • Supporting Information S1 enhancement. Here we describe a unique hydrothermal plume time series of annual (or more frequent) • Figure S1 fi • Data Set S1 observations at Axial Seamount vent elds from 1985 through 2017, missing only 7 years. Axial, a hot spot • Data Set S2 volcano astride the Juan de Fuca Ridge, experienced eruptions in 1998, 2011, and 2015. In 1998 and 2011 • Data Set S3 lava flooded the SE caldera and south rift zone, but in 2015 most lava was extruded in a series of flows • Data Set S4 extending ~20 km down the north rift zone. -
Coastal and Marine Ecological Classification Standard (2012)
FGDC-STD-018-2012 Coastal and Marine Ecological Classification Standard Marine and Coastal Spatial Data Subcommittee Federal Geographic Data Committee June, 2012 Federal Geographic Data Committee FGDC-STD-018-2012 Coastal and Marine Ecological Classification Standard, June 2012 ______________________________________________________________________________________ CONTENTS PAGE 1. Introduction ..................................................................................................................... 1 1.1 Objectives ................................................................................................................ 1 1.2 Need ......................................................................................................................... 2 1.3 Scope ........................................................................................................................ 2 1.4 Application ............................................................................................................... 3 1.5 Relationship to Previous FGDC Standards .............................................................. 4 1.6 Development Procedures ......................................................................................... 5 1.7 Guiding Principles ................................................................................................... 7 1.7.1 Build a Scientifically Sound Ecological Classification .................................... 7 1.7.2 Meet the Needs of a Wide Range of Users ...................................................... -
Articles Ranging in Resents Both Gravitational Acceleration and the Effect of Bed Size from Tens of Meters to a Few Centimeters in Diameter
Nat. Hazards Earth Syst. Sci., 6, 671–685, 2006 www.nat-hazards-earth-syst-sci.net/6/671/2006/ Natural Hazards © Author(s) 2006. This work is licensed and Earth under a Creative Commons License. System Sciences Numerical simulation of tsunami generation by cold volcanic mass flows at Augustine Volcano, Alaska C. F. Waythomas1, P. Watts2, and J. S. Walder3 1U.S. Geological Survey, Alaska Volcano Observatory, Anchorage, AK, USA 2Applied Fluids Engineering Inc., Long Beach, CA, USA 3U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, WA, USA Received: 18 April 2006 – Revised: 22 June 2006 – Accepted: 22 June 2006 – Published: 26 July 2006 Abstract. Many of the world’s active volcanoes are situated 1 Introduction on or near coastlines. During eruptions, diverse geophysical mass flows, including pyroclastic flows, debris avalanches, Many of the world’s active volcanoes are located within a and lahars, can deliver large volumes of unconsolidated de- few tens of kilometers of the sea or other large bodies of wa- bris to the ocean in a short period of time and thereby gen- ter. During eruptions, large volumes of volcaniclastic debris erate tsunamis. Deposits of both hot and cold volcanic mass may enter nearby water bodies, and under certain conditions, flows produced by eruptions of Aleutian arc volcanoes are this process may initiate tsunamis (Tinti et al., 1999; Tinti exposed at many locations along the coastlines of the Bering et al., 2003). Worldwide, tsunamis caused by volcanic erup- Sea, North Pacific Ocean, and Cook Inlet, indicating that tions are somewhat infrequent (Latter, 1981); however, doc- the flows entered the sea and in some cases may have ini- umented historical cases illustrate that loss of life and prop- tiated tsunamis. -
Cenozoic Changes in Pacific Absolute Plate Motion A
CENOZOIC CHANGES IN PACIFIC ABSOLUTE PLATE MOTION A THESIS SUBMITTED TO THE GRADUATE DIVISION OF THE UNIVERSITY OF HAWAI`I IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN GEOLOGY AND GEOPHYSICS DECEMBER 2003 By Nile Akel Kevis Sterling Thesis Committee: Paul Wessel, Chairperson Loren Kroenke Fred Duennebier We certify that we have read this thesis and that, in our opinion, it is satisfactory in scope and quality as a thesis for the degree of Master of Science in Geology and Geophysics. THESIS COMMITTEE Chairperson ii Abstract Using the polygonal finite rotation method (PFRM) in conjunction with the hotspot- ting technique, a model of Pacific absolute plate motion (APM) from 65 Ma to the present has been created. This model is based primarily on the Hawaiian-Emperor and Louisville hotspot trails but also incorporates the Cobb, Bowie, Kodiak, Foundation, Caroline, Mar- quesas and Pitcairn hotspot trails. Using this model, distinct changes in Pacific APM have been identified at 48, 27, 23, 18, 12 and 6 Ma. These changes are reflected as kinks in the linear trends of Pacific hotspot trails. The sense of motion and timing of a number of circum-Pacific tectonic events appear to be correlated with these changes in Pacific APM. With the model and discussion presented here it is suggested that Pacific hotpots are fixed with respect to one another and with respect to the mantle. If they are moving as some paleomagnetic results suggest, they must be moving coherently in response to large-scale mantle flow. iii List of Tables 4.1 Initial hotspot locations . -
This Report Is Preliminary and Has Not Bee Reviewed for Conformity with US
UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY Northeast-trending subcrustal fault transects western Washington by Kenneth F. Fox, Jr.* Open-File Report 83-398 This report is preliminary and has not bee reviewed for conformity with U.S Geological Survey editorial standards and stratigraphic nomenclature. *U.S. Geological Survey 3^5 Middlefield Road Menlo Park, California 9^025 Page Table of Contents Tectonic setting......................................................... 1 Seisraicity............................................................... 4 Discussion............................................................... 4 References cited......................................................... 6 Figures Figure 1. Magnetic anomalies in the northeastern Pacific................ 8 Figure 2. Bathymetry at intersection of Columbia lineament and Blanco fracture zone................................................. 9 Figure 3. Plane vector representation of movement of Gorda plate........ 10 Figure 4. Reconstruction of Pacific-Juan de Fuca plate geometry 2 m.y. before present................................................ 11 Figure 5. Epicenters of historical earthquakes with intensity greater than V........................................................ 12 TECTONIC SETTING The north-trending magnetic anomalies of the Juan de Fuca plate are off set along two conspicuous northeast-trending lineaments (fig. 1), named the Columbia offset and the Destruction offset by Carlson (1981). The northeast ward projections of these lineaments intersect the continental area of western Washington, hence are of potential significance to the tectonics of the Pacific Northwest region. Pavoni (1966) suggested that these lineaments were left-lateral faults, and that the Columbia, 280 km in length, had 52 km of offset, and the Destruction, with a length of 370 km, had 75 km of offset. Based on Vine's (1968) correlation of the magnetic anomalies mapped in this area by Raff and Mason (1961), with the magnetic reversal time scale, Silver (1971b, p. -
Geology and Geochemistry of the Southern Explorer Ridge Seafloor Hydrothermal Site Using an Integrated GIS Database and 3D Modeling
Physiology, Geology and Geochemistry of the Southern Explorer Ridge Seafloor Hydrothermal Site Using an Integrated GIS Database and 3D Modeling Yannick C. Beaudoin A thesis subrnitted in conformity with the requirements for the degree of Master of Science Graduate Department of Geology University of Toronto O March 2001 National Library Bibliothèque nationale If1 of Canada du Canada Acquisitions and Acquisitions et Bibliogmphic Sewices services bibliogrâphiques 395 Wellington Street 395. rue Wellington Ottawa ON K1A ON4 Ottawa ON K1A ON4 Canada Canada Yow Ne votro nlfémma Our fiie Notre réfdrenw The author has granted a non- L'auteur a accordé une licence non exclusive licence allowing the exciusive permettant à la National Lhrary of Canada to Bibliothèque nationale du Canada de reproduce, loan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfiche/film, de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts fkom it Ni la thèse ni des extraits substantiels may be printed or othe*se de celle-ci ne doivent être imprimes reproduced without the author's ou autrement reproduits sans son permission. autorisation. Physiology, Geology and Geochemistry of the Southern Explorer Ridge Seafloor Hydrothermal Site Using an Integrated GIS Database and 3D Modeling by Yannick Beaudoin in partial fulfillment of the requirements for the degree of Master's of Science, March 2001, Graduate Department of Geology, University of Toronto Southem Explorer Ridge (SER) is an anomalously-rate shallow, intemediate spreading ridge located 200 kilometers off the west Coast of Vancouver Island, Canada. -
OCEAN/ESS 410 1 Lab 3. the Juan De Fuca Plate Please Write out Your
OCEAN/ESS 410 Lab 3. The Juan de Fuca Plate Please write out your answers on a separate sheet of paper. In this exercise you are going to be looking at the bathymetry of the Juan de Fuca plate region, identifying interesting features and their characteristics, and attempting to interpret what you see. Some of the questions may be difficult for you to answer now (although hopefully not at the end of the Quarter) – part of the objective is to get you to look carefully at the maps and think rather that immediately writing down an answer. The Instructor and TAs will be coming around the lab answering questions. Figure 1 shows the plate boundaries for the Juan de Fuca plate region and you will use this as your road map as you explore the Juan de Fuca plate with the program GeoMapApp, a versatile program that is used by researchers to look at bathymetry and other seafloor data. To run GeoMapApp do the following 1. Start GeoMapApp on the lab computer from the Start menu or from the Desktop Icon if you have one. If it asks you to install a new version you do not have to. 2. Select the default Mercator Base Map (left hand map) 3. Learn to use the “Zoom In”, “Zoom Out” and “Pan the Map” tools. You can use the “Zoom In” tool either by clicking on the map or holding the mouse button down to rubber-band a box of interest. The Overlays menu allows you to add a Distance Scale and Color Bar. -
Recent Movements of the Juan De Fuca Plate System
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 89, NO. B8, PAGES 6980-6994, AUGUST 10, 1984 Recent Movements of the Juan de Fuca Plate System ROBIN RIDDIHOUGH! Earth PhysicsBranch, Pacific GeoscienceCentre, Departmentof Energy, Mines and Resources Sidney,British Columbia Analysis of the magnetic anomalies of the Juan de Fuca plate system allows instantaneouspoles of rotation relative to the Pacific plate to be calculatedfrom 7 Ma to the present.By combiningthese with global solutions for Pacific/America and "absolute" (relative to hot spot) motions, a plate motion sequencecan be constructed.This sequenceshows that both absolute motions and motions relative to America are characterizedby slower velocitieswhere younger and more buoyant material enters the convergencezone: "pivoting subduction."The resistanceprovided by the youngestportion of the Juan de Fuca plate apparently resulted in its detachmentat 4 Ma as the independentExplorer plate. In relation to the hot spot framework, this plate almost immediately began to rotate clockwisearound a pole close to itself such that its translational movement into the mantle virtually ceased.After 4 Ma the remainder of the Juan de Fuca plate adjusted its motion in responseto the fact that the youngest material entering the subductionzone was now to the south. Differencesin seismicityand recent uplift betweennorthern and southernVancouver Island may reflect a distinction in tectonicstyle betweenthe "normal" subductionof the Juan de Fuca plate to the south and a complex "underplating"occurring as the Explorer plate is overriddenby the continent.The history of the Explorer plate may exemplifythe conditionsunder which the self-drivingforces of small subductingplates are overcomeby the influenceof larger, adjacent plates. The recent rapid migration of the absolutepole of rotation of the Juan de Fuca plate toward the plate suggeststhat it, too, may be nearingthis condition. -
Exploring Submarine Arc Volcanoes Steven Carey University of Rhode Island, [email protected]
University of Rhode Island DigitalCommons@URI Graduate School of Oceanography Faculty Graduate School of Oceanography Publications 2007 Exploring Submarine Arc Volcanoes Steven Carey University of Rhode Island, [email protected] Haraldur Sigurdsson University of Rhode Island Follow this and additional works at: https://digitalcommons.uri.edu/gsofacpubs Terms of Use All rights reserved under copyright. Citation/Publisher Attribution Carey, S., and H. Sigurdsson. 2007. Exploring submarine arc volcanoes. Oceanography 20(4):80–89, https://doi.org/10.5670/ oceanog.2007.08. Available at: https://doi.org/10.5670/oceanog.2007.08 This Article is brought to you for free and open access by the Graduate School of Oceanography at DigitalCommons@URI. It has been accepted for inclusion in Graduate School of Oceanography Faculty Publications by an authorized administrator of DigitalCommons@URI. For more information, please contact [email protected]. This article has This been published in 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 portionthe ofwith any permitted articleonly photocopy by is of machine, reposting, this means or collective or other redistirbution SP ec I A L Iss U E On Ocean E X P L O R ATIO N Oceanography , Volume 20, Number 4, a quarterly journal of The 20, Number 4, a quarterly , Volume O ceanography Society. Copyright 2007 by The 2007 by Copyright Society. ceanography Exploring O ceanography Society. All rights All reserved. Society. ceanography O Submarine Arc Volcanoes or Th e [email protected] Send Society. ceanography to: correspondence all B Y S T even C A R E Y an D H A R A LDUR SIGURD ss O N Three quarters of Earth’s volcanic activ- although a significant part of arc volca- tion of tsunamis (Latter, 1981).