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Alexander the Great's Tombolos at Tyre and Alexandria, Eastern Mediterranean ⁎ N
Available online at www.sciencedirect.com Geomorphology 100 (2008) 377–400 www.elsevier.com/locate/geomorph Alexander the Great's tombolos at Tyre and Alexandria, eastern Mediterranean ⁎ N. Marriner a, , J.P. Goiran b, C. Morhange a a CNRS CEREGE UMR 6635, Université Aix-Marseille, Europôle de l'Arbois, BP 80, 13545 Aix-en-Provence cedex 04, France b CNRS MOM Archéorient UMR 5133, 5/7 rue Raulin, 69365 Lyon cedex 07, France Received 25 July 2007; received in revised form 10 January 2008; accepted 11 January 2008 Available online 2 February 2008 Abstract Tyre and Alexandria's coastlines are today characterised by wave-dominated tombolos, peculiar sand isthmuses that link former islands to the adjacent continent. Paradoxically, despite a long history of inquiry into spit and barrier formation, understanding of the dynamics and sedimentary history of tombolos over the Holocene timescale is poor. At Tyre and Alexandria we demonstrate that these rare coastal features are the heritage of a long history of natural morphodynamic forcing and human impacts. In 332 BC, following a protracted seven-month siege of the city, Alexander the Great's engineers cleverly exploited a shallow sublittoral sand bank to seize the island fortress; Tyre's causeway served as a prototype for Alexandria's Heptastadium built a few months later. We report stratigraphic and geomorphological data from the two sand spits, proposing a chronostratigraphic model of tombolo evolution. © 2008 Elsevier B.V. All rights reserved. Keywords: Tombolo; Spit; Tyre; Alexandria; Mediterranean; Holocene 1. Introduction Courtaud, 2000; Browder and McNinch, 2006); (2) establishing a typology of shoreline salients and tombolos (Zenkovich, 1967; The term tombolo is used to define a spit of sand or shingle Sanderson and Eliot, 1996); and (3) modelling the geometrical linking an island to the adjacent coast. -
NATURAL ENGLAND Geomorphological Advice in Respect of Pagham Spit (West Sussex). April 2013
Pagham Spit Advice 2013 NATURAL ENGLAND Geomorphological Advice in respect of Pagham spit (West Sussex). April 2013 Professor Julian Orford Queen’s University, Belfast Pagham Spit Advice 2013 Natural England Advice Request 1) Could the two recycling operations: i) 2010 and ii) 2012-13 have had a detrimental impact on the site’s functioning and its geomorphological interest? 2) What are the best sources for the current sediment recycling proposals? Note two joint operations to be considered: i) HW erosion at western Pagham and ii) re- armouring of the exposed armoured groyne 3) Is the channel likely to close? 4) What are the possible ways in which the spit might develop, both in the short and longer term? Of these, which is the most likely? 5) Is the rock armour the most effective way to protect the properties? 6) Our current view is that the on-going evolution of the Church Norton spit is a key component in the conservation of the geomorphological interest of the SSSI. Are there other elements we should also be concerned about? Glossary Berm: A constructive wave-built beach face feature generally occurring at the swash reach associated with any particular high tide position. Cumulatively over the neap to spring tidal half-cycle, one berm is realized, associated with highest tidal position. On the falling spring- neap cycle, a series of berms may be realized at each successive lower position achieved by the swash-reach of each successive falling tidal level. Cannibalisation: The tendency for a beach system where the longshore sediment supply has reduced or failed, to use the existing beach sediment as a further source for subsequent longshore sediment transport down-drift. -
Whale Shark Rhincodon Typus Populations Along the West Coast of the Gulf of California and Implications for Management
Vol. 18: 115–128, 2012 ENDANGERED SPECIES RESEARCH Published online August 16 doi: 10.3354/esr00437 Endang Species Res Whale shark Rhincodon typus populations along the west coast of the Gulf of California and implications for management Dení Ramírez-Macías1,2,*, Abraham Vázquez-Haikin3, Ricardo Vázquez-Juárez1 1Centro de Investigaciones Biológicas del Noroeste, Mar Bermejo 195, Col. Playa Palo de Santa Rita, La Paz, Baja California Sur 23096, Mexico 2Tiburón Ballena México de Conciencia México, Manatí 4802, Col. Esperanza III, La Paz, Baja California Sur 23090, Mexico 3Asociación de Pesca Deportiva y Ecoturismo de Bahía de los Ángeles, Domicilio conocido Bahía de los Ángeles, Baja California 22980, Mexico ABSTRACT: We used photo-identification data collected from 2003 through 2009 to estimate pop- ulation structure, site fidelity, abundance, and movements of this species along the west coast of the Gulf of California to make recommendations for effective conservation and management. Of 251 whale sharks identified from 1784 photographs, 129 sharks were identified in Bahía de Los Ángeles and 125 in Bahía de La Paz. Only juveniles (mostly small) were found in these 2 bays. At Isla Espíritu Santo, we identified adult females; at Gorda Banks we identified 15 pregnant females. High re-sighting rates within and across years provided evidence of site fidelity among juvenile sharks in the 2 bays. Though the juveniles were not permanent residents, they used the areas regularly from year to year. A proportion of the juveniles spent days to a month or more in the coastal waters of the 2 bays before leaving, and periods of over a month outside the study areas before entering the bays again. -
A Scientific Forum on the Gulf of Mexico: the Islands in the Stream Concept
Proceedings: Gulf of Mexico Science Forum A Scientific Forum on the Gulf of Mexico: The Islands in the Stream Concept Proceedings of the Forum: 23 January 2008 Keating Education Center Mote Marine Laboratory Sarasota, Florida Proceedings: Gulf of Mexico Science Forum Table of Contents Forward (Ernest Estevez) .............................................................................................................4 Executive Summary.....................................................................................................................6 Acknowledgements ......................................................................................................................9 Organizing Committee ................................................................................................................9 Welcome and Introduction (Kumar Mahadevan and Daniel J. Basta) .....................................10 Introduction to the Forum (Billy D. Causey)...........................................................................12 Summary of Scientific Forum (John Ogden) ...........................................................................14 Panel 1: The Geological Setting...............................................................................................17 Geologic Underpinnings of the “Islands in the Stream”; West Florida Margin (Albert Hine and Stanley Locker)...............................................17 Shelf Edge of the Northwest Gulf of Mexico (Niall Slowey).............................................22 -
Shoreline Evolution Chesapeake Bay Shoreline City of Norfolk, Virginia
Shoreline Evolution Chesapeake Bay Shoreline City of Norfolk, Virginia Virginia Institute of Marine Science College of William & Mary Gloucester Point, Virginia 2005 Shoreline Evolution Chesapeake Bay Shoreline City of Norfolk, VA C. Scott Hardaway, Jr. 1 Donna A. Milligan 1 Lyle M. Varnell 2 Christine Wilcox 1 George R. Thomas 1 Travis R. Comer 1 Shoreline Studies Program 1 Department of Physical Sciences and Wetlands Program 2 Center for Coastal Resources Management Virginia Institute of Marine Science College of William & Mary Gloucester Point, Virginia 2005 This project was funded by the Virginia Department of Environmental Quality’s Coastal Resources Management Program through Grant #NA17OZ2355 of the National Oceanic and Atmospheric Administration, Office of Ocean and Coastal Resource Management, under the Coastal Zone Management Act of 1972, as amended. The views expressed herein are those of the authors and do not necessarily reflect the views of NOAA or any of its subagencies or DEQ. LIST OF FIGURES Figure 1. Location of the City of Norfolk within the Chesapeake Bay estuarine system...................2 Figure 2. Location of localities in the Dune Act with jurisdictional and non-jurisdictional localities noted. ...2 TABLE OF CONTENTS Figure 3. Geological map of the City of Norfolk (from Mixon et al., 1989). ...........................3 Figure 4. Index of shoreline plates.............................................................4 TABLE OF CONTENTS .................................................................. i Figure 5. Variability of dune and beach profiles within the City of Norfolk ............................7 Figure 6. Typical profile of a Chesapeake Bay dune system. ........................................7 LIST OF FIGURES ....................................................................... i Figure 7. Photo of the Norfolk shoreline showing dune site NF3.. ...................................9 Figure 8. -
Distribution and Sedimentary Characteristics of Tsunami Deposits
Sedimentary Geology 200 (2007) 372–386 www.elsevier.com/locate/sedgeo Distribution and sedimentary characteristics of tsunami deposits along the Cascadia margin of western North America ⁎ Robert Peters a, , Bruce Jaffe a, Guy Gelfenbaum b a USGS Pacific Science Center, 400 Natural Bridges Drive, Santa Cruz, CA 95060, United States b USGS 345 Middlefield Road, Menlo Park, CA 94025, United States Abstract Tsunami deposits have been found at more than 60 sites along the Cascadia margin of Western North America, and here we review and synthesize their distribution and sedimentary characteristics based on the published record. Cascadia tsunami deposits are best preserved, and most easily identified, in low-energy coastal environments such as tidal marshes, back-barrier marshes and coastal lakes where they occur as anomalous layers of sand within peat and mud. They extend up to a kilometer inland in open coastal settings and several kilometers up river valleys. They are distinguished from other sediments by a combination of sedimentary character and stratigraphic context. Recurrence intervals range from 300–1000 years with an average of 500–600 years. The tsunami deposits have been used to help evaluate and mitigate tsunami hazards in Cascadia. They show that the Cascadia subduction zone is prone to great earthquakes that generate large tsunamis. The inclusion of tsunami deposits on inundation maps, used in conjunction with results from inundation models, allows a more accurate assessment of areas subject to tsunami inundation. The application of sediment transport models can help estimate tsunami flow velocity and wave height, parameters which are necessary to help establish evacuation routes and plan development in tsunami prone areas. -
The Spit (Gold Coast Harbour) Local Area Plan
Part 6 Local Area Plans Division 2 Local Area Plans Chapter 26 The Spit (Gold Coast Harbour) 1.0 Intent The purpose of this Local Area Plan (LAP) is to provide for the maintenance of the open space character and environmental significance of The Spit (Gold Coast Harbour) and to facilitate and control recreational usage of park reserves. It is intended to consolidate and enhance marine-oriented development, including ancillary tourist and entertainment facilities, and to preserve the predominantly natural aspect of The Spit (Gold Coast Harbour). 2.0 Application 2.1 This LAP applies to all development subject to the Planning Scheme and located within the LAP area, as indicated in The Spit (Gold Coast Harbour) LAP Map 26.1 – Boundary. 2.2 The Table of Development indicated in Clause 6.0 identifies the level of assessment for development occurring within this LAP area. 2.3 The codes that may be relevant to the assessment of development in this LAP area are listed in Clause 7.0. 2.4 It should be noted that self assessable development is consistent with the intent and Desired Environmental Outcomes (DEOs) of this LAP, and therefore need only comply with the acceptable solutions of The Spit (Gold Coast Harbour) LAP Place Code contained in Clause 8.0 and any other acceptable solutions identified in the relevant codes explicitly referred to in Subclause 7.1. 2.5 The Spit (Gold Coast Harbour) is included within the study area for the Gold Coast City Harbour Study, a joint investigation currently underway between Council and the state government of future land use and development options for the southern Broadwater and its shores. -
States Vulnerable to Ocean Acidification
PACIFIC NORTHWEST IS AT HIGH RISK FOR ECONOMIC HARM DUE TO OCEAN ACIDIFICATION According to a new assessment of the U.S. communities most vul- nerable to ocean acidification, the Date Water Pacific Northwest is at high risk of Unfavorable Economic Sensitivity To Shellfish Score Other Factors economic harm. Communities and 2006 - 2030 High Algae Blooms 2031 - 2050 Medium High River Inputs governments can still take action, 2051 - 2070 Medium Upwelling 2071 - 2099 Medium Low researchers say. 2099 + Low MAP LEFT: The long-term economic impacts of ocean acidification are expected to be most severe in regions where ocean areas are acidifying soonest (black) and where the residents rely most on local shellfish for their livelihood (red). Local factors such as algae blooms from nutrient pollu- tion, local upwelling currents, and poorly buffered rivers (green, purple, blue) can amplify acidification locally. adapted by NRDC from Ekstrom et al., 2015 adapted by NRDC from Ekstrom et al., 2015 WHY IS THE PACIFIC NORTHWEST A HOTSPOT? ECONOMIC DEPENDENCE OCEAN VULNERABILITY A SALTY GOLDMINE. Shelled Some believe Puget Sound is the greatest oyster-growing mollusk fisheries in Washington region on the planet. Cold, clean and Oregon produce slightly water from deep currents off the more than $100 million annu- coast, a winding coastline with ally in direct sales. Though the thousands of inlets with sheltered economic benefits extend well water, and an abundant supply of beyond the value of the harvest. The estimated mountain-fed rivers all contribute to this perception. But this same formula has also total annual economic impact of aquaculture in put the region at risk from ocean acidification. -
EA for Cascadia Spring/Summer Survey 2020
Draft Environmental Assessment/Analysis of a Marine Geophysical Survey by R/V Marcus G. Langseth of the Cascadia Subduction Zone in the Northeast Pacific Ocean, Late Spring/Summer 2020 Prepared for Lamont-Doherty Earth Observatory 61 Route 9W, P.O. Box 1000 Palisades, NY 10964-8000 and National Science Foundation Division of Ocean Sciences 4201 Wilson Blvd., Suite 725 Arlington, VA 22230 by LGL Ltd., environmental research associates 22 Fisher St., POB 280 King City, Ont. L7B 1A6 21 November 2019 LGL Report FA0186-01A Table of Contents TABLE OF CONTENTS LIST OF FIGURES .......................................................................................................................................... iv LIST OF TABLES ............................................................................................................................................. v ABSTRACT .................................................................................................................................................... vi LIST OF ACRONYMS ..................................................................................................................................... ix I PURPOSE AND NEED ................................................................................................................................... 1 1.1 Mission of NSF ................................................................................................................................ 1 1.2 Purpose of and Need for the Proposed Action ................................................................................ -
Coastal Dynamics 2017 Paper No.222 1278 BYPASS in GROYNE FIELDS: CASE STUDY ALONG the LOBITO SPIT Sten Esbjørn Kristensen1, Ni
Coastal Dynamics 2017 Paper No.222 BYPASS IN GROYNE FIELDS: CASE STUDY ALONG THE LOBITO SPIT Sten Esbjørn Kristensen1, Nils Drønen2, Rolf Deigaard3, Berry Elfrink4 Abstract The Lobito spit, in Angola, is fronted by a groyne field along the entire length of the spit. The groynes were intended to halt the development of the spit, by lowering the littoral drift along the spit. The stability of the spit itself appears however to be threatened because beach sections along the downstream end are narrow, thus suggesting that the supply of sediment from the longshore transport cannot balance offshore losses. Aerial images from 2004 to 2015 show also a gradual filling of downdrift empty groyne compartments. Sediment budgets are formulated to support the two observations, 1) tendency for half-empty groyne compartments in downdrift end and 2) gradual filling of empty groyne compartments. The sediment budgets rely on an empirical expression for the bypass transport in groyne fields, which is based on modelling of 2D shoreline morphology of idealised groyne fields. Keywords: Groyne field, bypass transport, numerical modelling. 1. Introduction Coastal structures constitutes a perturbation to the natural morphological system. By investigating and understanding the natural response to such structures, we can learn much about the natural system and e.g. obtain knowledge about how to develop a morphological design that both reflects the coastal communities’ need for defences against erosion and flooding and is line with the rules of nature. The present study concerns a groyne field located along a sandy spit, where the groyne field has modified the littoral drift conditions and thereby changed the stability of the spit itself. -
Oceanography of the Pacific Northwest Coastal Ocean and Estuaries with Application to Coastal Ecosystems
Oceanography of the Pacific Northwest Coastal Ocean and Estuaries with Application to Coastal Ecosystems Barbara M. Hickey1 and Neil S. Banas School of Oceanography Box 355351 University of Washington, Seattle, WA 98195-7940 Tel.: 206 543 4737 e-mail: [email protected] Submitted to Estuaries May 2002 1Corresponding author. Hickey and Banas 2 Abstract This paper reviews and synthesizes recent results on both the coastal zone of the U.S. Pacific Northwest (PNW) and several of its estuaries, as well as presenting new data from the PNCERS program on links between the inner shelf and the estuaries, and smaller-scale estuarine processes. In general ocean processes are large-scale on this coast: this is true of both seasonal variations and event-scale upwelling-downwelling fluctuations, which are highly energetic. Upwelling supplies most of the nutrients available for production, although the intensity of upwelling increases southward while primary production is higher in the north, off the Washington coast. This discrepancy is attributable to mesoscale features: variations in shelf width and shape, submarine canyons, and the Columbia River plume. These and other mesoscale features (banks, the Juan de Fuca eddy) are important as well in transport and retention of planktonic larvae and harmful algae blooms. The coastal-plain estuaries, with the exception of the Columbia River, are relatively small, with large tidal forcing and highly seasonal direct river inputs that are low-to-negligible during the growing season. As a result primary production in the estuaries is controlled principally not by river-driven stratification but by coastal upwelling and bulk exchange with the ocean. -
A Precious Asset
Gulf St Vincent A PRECIOUS ASSET Gulf St Vincent A PRECIOUS AssET Introduction It is more than 70 years since Since that time, the Gulf has We need these people, and other William Light sailed up the eastern provided safe, reliable transport for members of the Gulf community, side of Gulf St Vincent, looking for most of our produce and material to share their knowledge, to the entrance to a harbour which needs, as well as fresh fish, coastal make all users of the Gulf aware had been reported by the explorer, living, recreation and inspiration. of its value, its benefits and its Captain Collet Barker, and the In return we have muddied its vulnerability. It is time for us all to whaling captain, John Jones. waters with stormwater, effluent learn more about Gulf St Vincent, He found waters calm and clear and industrial wastes, bulldozed to recognise the priceless asset enough to avoid shoals and to its dunes, locked up sand under we have, and to do our utmost to safely anchor through the spring houses and greedily exploited its reverse the trail of destruction we gales blowing from the south-west. marine life. Just reflect a moment have left in the last 00 years. Perhaps even he saw sea eagles on what Adelaide in particular, and The more we know of the Gulf, fishing or nesting in the low trees South Australia as a whole, would its physical nature and marine life, and bushes on the dunes, which be like without Gulf St Vincent, to the more readily we recognise extended along the coast from realise the importance of the Gulf the threats posed by increasing Brighton to the Port River.