Measuring Currents in Submarine Canyons: Technological and Scientifi C Progress in the Past 30 Years
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Turbidity Current Flow Over an Erodible Obstacle and Phases of Sediment Wave Generation Moshe Strauss1,2 and Michael E
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 117, C06007, doi:10.1029/2011JC007539, 2012 Turbidity current flow over an erodible obstacle and phases of sediment wave generation Moshe Strauss1,2 and Michael E. Glinsky2,3,4 Received 24 August 2011; revised 21 March 2012; accepted 20 April 2012; published 7 June 2012. [1] We study the flow of particle-laden turbidity currents down a slope and over an obstacle. A high-resolution 2-D computer simulation model is used, based on the Navier-Stokes equations. It includes poly-disperse particle grain sizes in the current and substrate. Particular attention is paid to the erosion and deposition of the substrate particles, including application of an active layer model. Multiple flows are modeled from a lock release that can show the development of sediment waves (SW). These are stream-wise waves that are triggered by the increasing slope on the downstream side of the obstacle. The initial obstacle is completely erased by the resuspension after a few flows leading to self consistent and self generated SW that are weakly dependant on the initial obstacle. The growth of these waves is directly related to the turbidity current being self sustaining, that is, the net erosion is more than the net deposition. Four system parameters are found to influence the SW growth: (1) slope, (2) current lock height, (3) grain lock concentration, and (4) particle diameters. Three phases are discovered for the system: (1) “no SW,” (2) “SW buildup,” and (3) “SW growth”. The second phase consists of a soliton-like SW structure with a preserved shape. -
Littoral Cells, Sand Budgets, and Beaches: Understanding California S
LITTORAL CELLS, SAND BUDGETS, AND BEACHES: UNDERSTANDING CALIFORNIA’ S SHORELINE KIKI PATSCH GARY GRIGGS OCTOBER 2006 INSTITUTE OF MARINE SCIENCES UNIVERSITY OF CALIFORNIA, SANTA CRUZ CALIFORNIA DEPARTMENT OF BOATING AND WATERWAYS CALIFORNIA COASTAL SEDIMENT MANAGEMENT WORKGROUP Littoral Cells, Sand Budgets, and Beaches: Understanding California’s Shoreline By Kiki Patch Gary Griggs Institute of Marine Sciences University of California, Santa Cruz California Department of Boating and Waterways California Coastal Sediment Management WorkGroup October 2006 Cover Image: Santa Barbara Harbor © 2002 Kenneth & Gabrielle Adelman, California Coastal Records Project www.californiacoastline.org Brochure Design & Layout Laura Beach www.LauraBeach.net Littoral Cells, Sand Budgets, and Beaches: Understanding California’s Shoreline Kiki Patsch Gary Griggs Institute of Marine Sciences University of California, Santa Cruz TABLE OF CONTENTS Executive Summary 7 Chapter 1: Introduction 9 Chapter 2: An Overview of Littoral Cells and Littoral Drift 11 Chapter 3: Elements Involved in Developing Sand Budgets for Littoral Cells 17 Chapter 4: Sand Budgets for California’s Major Littoral Cells and Changes in Sand Supply 23 Chapter 5: Discussion of Beach Nourishment in California 27 Chapter 6: Conclusions 33 References Cited and Other Useful References 35 EXECUTIVE SUMMARY he coastline of California can be divided into a set of dis- Beach nourishment or beach restoration is the placement of Ttinct, essentially self-contained littoral cells or beach com- sand on the shoreline with the intent of widening a beach that partments. These compartments are geographically limited and is naturally narrow or where the natural supply of sand has consist of a series of sand sources (such as rivers, streams and been signifi cantly reduced through human activities. -
Cumulated Bibliography of Biographies of Ocean Scientists Deborah Day, Scripps Institution of Oceanography Archives Revised December 3, 2001
Cumulated Bibliography of Biographies of Ocean Scientists Deborah Day, Scripps Institution of Oceanography Archives Revised December 3, 2001. Preface This bibliography attempts to list all substantial autobiographies, biographies, festschrifts and obituaries of prominent oceanographers, marine biologists, fisheries scientists, and other scientists who worked in the marine environment published in journals and books after 1922, the publication date of Herdman’s Founders of Oceanography. The bibliography does not include newspaper obituaries, government documents, or citations to brief entries in general biographical sources. Items are listed alphabetically by author, and then chronologically by date of publication under a legend that includes the full name of the individual, his/her date of birth in European style(day, month in roman numeral, year), followed by his/her place of birth, then his date of death and place of death. Entries are in author-editor style following the Chicago Manual of Style (Chicago and London: University of Chicago Press, 14th ed., 1993). Citations are annotated to list the language if it is not obvious from the text. Annotations will also indicate if the citation includes a list of the scientist’s papers, if there is a relationship between the author of the citation and the scientist, or if the citation is written for a particular audience. This bibliography of biographies of scientists of the sea is based on Jacqueline Carpine-Lancre’s bibliography of biographies first published annually beginning with issue 4 of the History of Oceanography Newsletter (September 1992). It was supplemented by a bibliography maintained by Eric L. Mills and citations in the biographical files of the Archives of the Scripps Institution of Oceanography, UCSD. -
Feasibility Study of an Artifical Sandy Beach at Batumi, Georgia
FEASIBILITY STUDY OF AN ARTIFICAL SANDY BEACH AT BATUMI, GEORGIA ARCADIS/TU DELFT : MSc Report FEASIBILITY STUDY OF AN ARTIFICAL SANDY BEACH AT BATUMI, GEORGIA Date May 2012 Graduate C. Pepping Educational Institution Delft University of Technology, Faculty Civil Engineering & Geosciences Section Hydraulic Engineering, Chair of Coastal Engineering MSc Thesis committee Prof. dr. ir. M.J.F. Stive Delft University of Technology Dr. ir. M. Zijlema Delft University of Technology Ir. J. van Overeem Delft University of Technology Ir. M.C. Onderwater ARCADIS Nederland BV Company ARCADIS Nederland BV, Division Water PREFACE Preface This Master thesis is the final part of the Master program Hydraulic Engineering of the chair Coastal Engineering at the faculty Civil Engineering & Geosciences of the Delft University of Technology. This research is done in cooperation with ARCADIS Nederland BV. The report represents the work done from July 2011 until May 2012. I would like to thank Jan van Overeem and Martijn Onderwater for the opportunity to perform this research at ARCADIS and the opportunity to graduate on such an interesting subject with many different aspects. I would also like to thank Robbin van Santen for all his help and assistance for the XBeach model. Furthermore I owe a special thanks to my graduation committee for the valuable input and feedback: Prof. dr. ir. M.J.F. Stive (Delft University of Technology) for his support and interest in my graduation work; Dr. ir. M. Zijlema (Delft University of Technology) for his support and reviewing the report; ir. J. van Overeem (Delft University of Technology ) for his supervisions, useful feedback and help, support and for reviewing the report; and ir. -
Recent Sediments of the Monterey Deep-Sea Fan
UC Berkeley Hydraulic Engineering Laboratory Reports Title Recent Sediments of the Monterey Deep-Sea Fan Permalink https://escholarship.org/uc/item/5f440431 Author Wilde, Pat Publication Date 1965-05-01 Peer reviewed eScholarship.org Powered by the California Digital Library University of California RECENT SEDIMENTS OF THE MONTEREY DEEP-SEA FAN A thesis presented by Pat Wilde to The Department of Geological Sciences in partial fulfillment of the requirements for the degree of Doc tor of Philosophy in the subject of Geology Harvard Univer sity Cambridge, Massachusetts May 1965 Copyright reserved by the author University of California Hydraulic Engineering Laboratory Submitted under Contract DA- 49- 055-CIV-ENG- 63-4 with the Coastal Engineering Research Center, U. S. Army Technical Report No. HEL-2-13 RECENT SEDIMENTS OF THE MONTEREY DEEP-SEA FAN by Pat Wilde Berkeley, California May, 1965 CONTENTS Page Abstract ................... 1 Introduction ...................... 5 Definition ..................... 5 Location ..................... 5 Regional Setting .............. 8 Subjects of Investigation ............... 9 Sources of Data .................. 10 Acknowledgements ................ 10 Geomorphology ..................11 Major Features ..............'11 FanSlope ................... 11 Under sea Positive Relief ............15 Submarine Canyon-Channel Systems . 16 Hydraulic Geometry ................ 19 Calculations ............... 19 Comparison with other Channel Systems ..30 Lithology ........................32 Sampling Techniques ............... -
Dynamics of Beach Sand Made Easy
Dynamics of Beaches Made Easy Page 1 Dynamics Of Beaches Made Easy San Diego County Chapter of the Surfrider Foundation 1. Introduction Beaches are made up of more than just sand. In California beaches are generally formed by erosion of uplifted plates resulting in cliff backed beaches or in the delta areas of rivers or watersheds. Beach sand is an important element of beaches but not the only element. Wavecut platforms or tidal terraces are equally important in many areas of San Diego. The movement of beach sand is governed by many complex processes and variables. However, there are a few very basic elements that tend to control not only how much sand ends up on our beaches, but also how much sand exists near enough to the shore to be deposited on the beach under favorable conditions. The following is a brief description of the most important issues influencing the current condition of our local beaches with respect to sand. Dynamics of Beaches Made Easy Page 2 2. Geology The geology of San Diego County varies from sea cliffs to sandy beaches. Beaches are generally found at the mouths of lagoons or in the lagoon or river outfalls. Cliffs formed by tectonic activity and the erosion via marine forces deserve special mention. Much of San Diego’s coastline consists of a wavecut platform sometimes referred to as a tidal terrace. A wavecut platform is formed where a seacliff is eroded by marine action, meaning waves, resulting in the deposition of cliff material and formation of a bedrock area where erosion occurred. -
22–25 Oct. GSA 2017 Annual Meeting & Exposition
22–25 Oct. GSA 2017 Annual Meeting & Exposition JULY 2017 | VOL. 27, NO. 7 NO. 27, | VOL. 2017 JULY A PUBLICATION OF THE GEOLOGICAL SOCIETY OF AMERICA® JULY 2017 | VOLUME 27, NUMBER 7 SCIENCE 4 Extracting Bulk Rock Properties from Microscale Measurements: Subsampling and Analytical Guidelines M.C. McCanta, M.D. Dyar, and P.A. Dobosh GSA TODAY (ISSN 1052-5173 USPS 0456-530) prints news Cover: Mount Holyoke College astronomy students field-testing a and information for more than 26,000 GSA member readers and subscribing libraries, with 11 monthly issues (March/ Raman BRAVO spectrometer for field mineral identification, examin- April is a combined issue). GSA TODAY is published by The ing pegmatite minerals crosscutting a slightly foliated hornblende Geological Society of America® Inc. (GSA) with offices at quartz monzodiorite and narrow aplite dikes exposed in the spillway 3300 Penrose Place, Boulder, Colorado, USA, and a mail- of the Quabbin Reservoir. All three units are part of the Devonian ing address of P.O. Box 9140, Boulder, CO 80301-9140, USA. GSA provides this and other forums for the presentation Belchertown igneous complex in central Massachusetts, USA. of diverse opinions and positions by scientists worldwide, See related article, p. 4–9. regardless of race, citizenship, gender, sexual orientation, religion, or political viewpoint. Opinions presented in this publication do not reflect official positions of the Society. © 2017 The Geological Society of America Inc. All rights reserved. Copyright not claimed on content prepared GSA 2017 Annual Meeting & Exposition wholly by U.S. government employees within the scope of their employment. Individual scientists are hereby granted 11 Abstracts Deadline permission, without fees or request to GSA, to use a single figure, table, and/or brief paragraph of text in subsequent 12 Education, Careers, and Mentoring work and to make/print unlimited copies of items in GSA TODAY for noncommercial use in classrooms to further 13 Feed Your Brain—Lunchtime Enlightenment education and science. -
Deep-Sea Research Part I
Deep–Sea Research I 161 (2020) 103300 Contents lists available at ScienceDirect Deep-Sea Research Part I journal homepage: http://www.elsevier.com/locate/dsri Direct evidence of a high-concentration basal layer in a submarine turbidity current Zhiwen Wang a, Jingping Xu b,c,*, Peter J. Talling d, Matthieu J.B. Cartigny d, Stephen M. Simmons e, Roberto Gwiazda f, Charles K. Paull f, Katherine L. Maier g, Daniel R. Parsons e a College of Marine and Geosciences, Ocean University of China, 238 Songling Rd., Qingdao, Shandong, 266100, China b Department of Ocean Science and Engineering, Southern University of Science and Technology, 1088 Xueyuan Rd., Shenzhen, Guangdong, 518055, China c Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266061, China d Department of Earth Sciences and Geography, University of Durham, South Road, Durham, DH1 3LE, United Kingdom e Department of Geography, Environment and Earth Sciences, University of Hull, Cottingham Road, Hull, HU6 7RX, United Kingdom f Monterey Bay Aquarium Research Institute, 7700 Sandholdt Rd., Moss Landing, CA, 95039, USA g Pacific Coastal and Marine Science Center, U.S. Geological Survey, 2885 Mission St., Santa Cruz, CA, 95060, USA ARTICLE INFO ABSTRACT Keywords: Submarine turbidity currents are one of the most important sediment transfer processes on earth. Yet the Turbidity currents fundamental nature of turbidity currents is still debated; especially whether they are entirely dilute and tur Sediment concentration bulent, or a thin and dense basal layer drives the flow. This major knowledge gap is mainly due to a near- Seawater conductivity complete lack of direct measurements of sediment concentration within active submarine flows. -
Turbidites in a Jar
Activity— Turbidites in a Jar Sand Dikes & Marine Turbidites Paleoseismology is the study of the timing, location, and magnitude of prehistoric earthquakes preserved in the geologic record. Knowledge of the pattern of earthquakes in a region and over long periods of time helps to understand the long- term behavior of faults and seismic zones and is used to forecast the future likelihood of damaging earthquakes. Introduction Note: Glossary is in the activity description Sand dikes are sedimentary dikes consisting of sand that has been squeezed or injected upward into a fissure during Science Standards an earthquake. (NGSS; pg. 287) To figure out the earthquake hazard of an area, scientists need to know how often the largest earthquakes occur. • From Molecules to Organisms—Structures Unfortunately (from a scientific perspective), the time and Processes: MS-LS1-8 between major earthquakes is much longer than the • Motion and Stability—Forces and time period for which we have modern instrumental Interactions: MS-PS2-2 measurements or even historical accounts of earthquakes. • Earth’s Place in the Universe: MS-ESS1-4, Fortunately, scientists have found a sufficiently long record HS-ESS1-5 of past earthquakes that is preserved in the rock and soil • Earth’s Systems: HS-ESS2-1, MS-ESS2-2, beneath our feet. The unraveling of this record is the realm MS-ESS2-3 of a field called “paleoseismology.” • Earth and Human Activity: HS-ESS3-1, In the Central United States, abundant sand blows are MS-ESS3-2 studied by paleoseismologists. These patches of sand erupt onto the ground when waves from a large earthquake pass through wet, loose sand. -
Breaching Flow Slides and the Associated Turbidity Current
Journal of Marine Science and Engineering Article Breaching Flow Slides and the Associated Turbidity Current Said Alhaddad * , Robert Jan Labeur and Wim Uijttewaal Environmental Fluid Mechanics Section, Faculty of Civil Engineering and Geosciences, Delft University of Technology, 2628 CN Delft, The Netherlands; [email protected] (R.J.L.); [email protected] (W.U.) * Correspondence: [email protected] Received: 6 December 2019; Accepted: 14 January 2020; Published: 21 January 2020 Abstract: This paper starts with surveying the state-of-the-art knowledge of breaching flow slides, with an emphasis on the relevant fluid mechanics. The governing physical processes of breaching flow slides are explained. The paper highlights the important roles of the associated turbidity current and the frequent surficial slides in increasing the erosion rate of sediment. It also identifies the weaknesses of the current breaching erosion models. Then, the three-equation model of Parker et al. is utilised to describe the coupled processes of breaching and turbidity currents. For comparison’s sake, the existing breaching erosion models are considered: Breusers, Mastbergen and Van Den Berg, and Van Rhee. The sand erosion rate and hydrodynamics of the current vary substantially between the erosion models. Crucially, these erosion models do not account for the surficial slides, nor have they been validated due to the scarcity of data on the associated turbidity current. This paper motivates further experimental studies, including detailed flow measurements, to develop an advanced erosion model. This will improve the fidelity of numerical simulations. Keywords: flow slide; breaching; turbidity current; sediment entrainment; sediment pick-up function; erosion velocity 1. -
Mapping the Canyon
Deep East 2001— Grades 9-12 Focus: Bathymetry of Hudson Canyon Mapping the Canyon FOCUS Part III: Bathymetry of Hudson Canyon ❒ Library Books GRADE LEVEL AUDIO/VISUAL EQUIPMENT 9 - 12 Overhead Projector FOCUS QUESTION TEACHING TIME What are the differences between bathymetric Two 45-minute periods maps and topographic maps? SEATING ARRANGEMENT LEARNING OBJECTIVES Cooperative groups of two to four Students will be able to compare and contrast a topographic map to a bathymetric map. MAXIMUM NUMBER OF STUDENTS 30 Students will investigate the various ways in which bathymetric maps are made. KEY WORDS Topography Students will learn how to interpret a bathymet- Bathymetry ric map. Map Multibeam sonar ADAPTATIONS FOR DEAF STUDENTS Canyon None required Contour lines SONAR MATERIALS Side-scan sonar Part I: GLORIA ❒ 1 Hudson Canyon Bathymetry map trans- Echo sounder parency ❒ 1 local topographic map BACKGROUND INFORMATION ❒ 1 USGS Fact Sheet on Sea Floor Mapping A map is a flat representation of all or part of Earth’s surface drawn to a specific scale Part II: (Tarbuck & Lutgens, 1999). Topographic maps show elevation of landforms above sea level, ❒ 1 local topographic map per group and bathymetric maps show depths of land- ❒ 1 Hudson Canyon Bathymetry map per group forms below sea level. The topographic eleva- ❒ 1 Hudson Canyon Bathymetry map trans- tions and the bathymetric depths are shown parency ❒ with contour lines. A contour line is a line on a Contour Analysis Worksheet map representing a corresponding imaginary 59 Deep East 2001— Grades 9-12 Focus: Bathymetry of Hudson Canyon line on the ground that has the same elevation sonar is the multibeam sonar. -
What Is the Use of the History of Geology to a Practicing Geologist? the Propaedeutical Case of Stratigraphy
What Is the Use of the History of Geology to a Practicing Geologist? The Propaedeutical Case of Stratigraphy A. M. Celâl Şengör* İstanbul Teknik Üniversitesi (İTÜ) Maden Fakültesi ve Avrasya Yerbilimleri Enstitüsü, Ayazağa 34810, Istanbul, Turkey ABSTRACT A practicing geologist can benefit from the history of geology professionally in two main ways: by learning about past mistakes so as not to repeat them and by finding out about different ways to discovery. In this article, I discuss some aspects of the history of stratigraphy and point out that the concept of a stratum has shoehorned geologists into thinking time and rock equivalent, which has led to some serious misinterpretations of geological phenomena, such as the timing of orogenic events and the charting of sea level changes. I call this the “tyranny of strata.” The very name of stratigraphy comes from strata, but what it does is simply deduce temporal relations from spatial relations of rock bodies, including fossils, by making certain assumptions about processes, that is, invoking inevitably a hypo- thetical step. What we have learned from looking at the history of geology is that empirical stratal correlation, even when well controlled by index fossils, can never yield perfect temporal correlation, and any assumption that it does is doomed to failure. Geology progresses in a direction that it may soon be possible to date every package of rock in a way to know what process is being dated and where exactly. We can correlate only processes in time hypothetically, not rock bodies empirically. This is the most important lesson a stratigrapher ought to have learned from the history of his or her subject.