Turbidity Currents Comparing Theory and Observation in the Lab
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Turbidity Criterion for the Protection of Coral Reef and Hardbottom Communities
DRAFT Implementation of the Turbidity Criterion for the Protection of Coral Reef and Hardbottom Communities Division of Environmental Assessment and Restoration Florida Department of Environmental Protection October 2020 Contents Section 1. Introduction ................................................................................................................................. 1 1.1 Purpose of Document .......................................................................................................................... 1 1.2 Background Information ..................................................................................................................... 1 1.3 Proposed Criterion and Rule Language .............................................................................................. 2 1.4 Threatened and Endangered Species Considerations .......................................................................... 5 1.5 Outstanding Florida Waters (OFW) Considerations ........................................................................... 5 1.6 Natural Factors Influencing Background Turbidity Levels ................................................................ 7 Section 2. Implementation in Permitting ..................................................................................................... 8 2.1 Permitting Information ........................................................................................................................ 8 2.2 Establishing Baseline (Pre-project) Levels ........................................................................................ -
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. -
National Primary Drinking Water Regulations
National Primary Drinking Water Regulations Potential health effects MCL or TT1 Common sources of contaminant in Public Health Contaminant from long-term3 exposure (mg/L)2 drinking water Goal (mg/L)2 above the MCL Nervous system or blood Added to water during sewage/ Acrylamide TT4 problems; increased risk of cancer wastewater treatment zero Eye, liver, kidney, or spleen Runoff from herbicide used on row Alachlor 0.002 problems; anemia; increased risk crops zero of cancer Erosion of natural deposits of certain 15 picocuries Alpha/photon minerals that are radioactive and per Liter Increased risk of cancer emitters may emit a form of radiation known zero (pCi/L) as alpha radiation Discharge from petroleum refineries; Increase in blood cholesterol; Antimony 0.006 fire retardants; ceramics; electronics; decrease in blood sugar 0.006 solder Skin damage or problems with Erosion of natural deposits; runoff Arsenic 0.010 circulatory systems, and may have from orchards; runoff from glass & 0 increased risk of getting cancer electronics production wastes Asbestos 7 million Increased risk of developing Decay of asbestos cement in water (fibers >10 fibers per Liter benign intestinal polyps mains; erosion of natural deposits 7 MFL micrometers) (MFL) Cardiovascular system or Runoff from herbicide used on row Atrazine 0.003 reproductive problems crops 0.003 Discharge of drilling wastes; discharge Barium 2 Increase in blood pressure from metal refineries; erosion 2 of natural deposits Anemia; decrease in blood Discharge from factories; leaching Benzene -
Mapping Turbidity Currents Using Seismic Oceanography Title Page Abstract Introduction 1 2 E
Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Ocean Sci. Discuss., 8, 1803–1818, 2011 www.ocean-sci-discuss.net/8/1803/2011/ Ocean Science doi:10.5194/osd-8-1803-2011 Discussions OSD © Author(s) 2011. CC Attribution 3.0 License. 8, 1803–1818, 2011 This discussion paper is/has been under review for the journal Ocean Science (OS). Mapping turbidity Please refer to the corresponding final paper in OS if available. currents using seismic E. A. Vsemirnova and R. W. Hobbs Mapping turbidity currents using seismic oceanography Title Page Abstract Introduction 1 2 E. A. Vsemirnova and R. W. Hobbs Conclusions References 1Geospatial Research Ltd, Department of Earth Sciences, Tables Figures Durham University, Durham DH1 3LE, UK 2Department of Earth Sciences, Durham University, Durham DH1 3LE, UK J I Received: 25 May 2011 – Accepted: 12 August 2011 – Published: 18 August 2011 J I Correspondence to: R. W. Hobbs ([email protected]) Published by Copernicus Publications on behalf of the European Geosciences Union. Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion 1803 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Abstract OSD Using a combination of seismic oceanographic and physical oceanographic data ac- quired across the Faroe-Shetland Channel we present evidence of a turbidity current 8, 1803–1818, 2011 that transports suspended sediment along the western boundary of the Channel. We 5 focus on reflections observed on seismic data close to the sea-bed on the Faroese Mapping turbidity side of the Channel below 900m. Forward modelling based on independent physi- currents using cal oceanographic data show that thermohaline structure does not explain these near seismic sea-bed reflections but they are consistent with optical backscatter data, dry matter concentrations from water samples and from seabed sediment traps. -
New York State Artificial Reef Plan and Generic Environmental Impact
TABLE OF CONTENTS EXECUTIVE SUMMARY ...................... vi 1. INTRODUCTION .......................1 2. MANAGEMENT ENVIRONMENT ..................4 2.1. HISTORICAL PERSPECTIVE. ..............4 2.2. LOCATION. .....................7 2.3. NATURAL RESOURCES. .................7 2.3.1 Physical Characteristics. ..........7 2.3.2 Living Resources. ............. 11 2.4. HUMAN RESOURCES. ................. 14 2.4.1 Fisheries. ................. 14 2.4.2 Archaeological Resources. ......... 17 2.4.3 Sand and Gravel Mining. .......... 18 2.4.4 Marine Disposal of Waste. ......... 18 2.4.5 Navigation. ................ 18 2.5. ARTIFICIAL REEF RESOURCES. ............ 20 3. GOALS AND OBJECTIVES .................. 26 3.1 GOALS ....................... 26 3.2 OBJECTIVES .................... 26 4. POLICY ......................... 28 4.1 PROGRAM ADMINISTRATION .............. 28 4.1.1 Permits. .................. 29 4.1.2 Materials Donations and Acquisitions. ... 31 4.1.3 Citizen Participation. ........... 33 4.1.4 Liability. ................. 35 4.1.5 Intra/Interagency Coordination. ...... 36 4.1.6 Program Costs and Funding. ......... 38 4.1.7 Research. ................. 40 4.2 DEVELOPMENT GUIDELINES .............. 44 4.2.1 Siting. .................. 44 4.2.2 Materials. ................. 55 4.2.3 Design. .................. 63 4.3 MANAGEMENT .................... 70 4.3.1 Monitoring. ................ 70 4.3.2 Maintenance. ................ 72 4.3.3 Reefs in the Exclusive Economic Zone. ... 74 4.3.4 Special Management Concerns. ........ 76 4.3.41 Estuarine reefs. ........... 76 4.3.42 Mitigation. ............. 77 4.3.43 Fish aggregating devices. ...... 80 i 4.3.44 User group conflicts. ........ 82 4.3.45 Illegal and destructive practices. .. 85 4.4 PLAN REVIEW .................... 88 5. ACTIONS ........................ 89 5.1 ADMINISTRATION .................. 89 5.2 RESEARCH ..................... 89 5.3 DEVELOPMENT .................... 91 5.4 MANAGEMENT .................... 96 6. ENVIRONMENTAL IMPACTS ................. 97 6.1 ECOSYSTEM IMPACTS. -
Measuring Currents in Submarine Canyons: Technological and Scientifi C Progress in the Past 30 Years
Exploring the Deep Sea and Beyond themed issue Measuring currents in submarine canyons: Technological and scientifi c progress in the past 30 years J.P. Xu U.S. Geological Survey, 345 Middlefi eld Road, MS-999, Menlo Park, California 94025, USA ABSTRACT 1. INTRODUCTION processes, and summarize and discuss several future research challenges constructed primar- The development and application of The publication of the American Association ily for submarine canyons in temperate climate, acoustic and optical technologies and of of Petroleum Geologists Studies in Geology 8: such as the California coast. accurate positioning systems in the past Currents in Submarine Canyons and Other Sea 30 years have opened new frontiers in the Valleys (Shepard et al., 1979) marked a signifi - 2. TECHNOLOGICAL ADVANCES submarine canyon research communities. cant milestone in submarine canyon research. IN CURRENT OBSERVATION IN This paper reviews several key advance- Although there had been studies on the topics of SUBMARINE CANYONS ments in both technology and science in the submarine canyon hydrodynamics and sediment fi eld of currents in submarine canyons since processes in various journals since the 1930s 2.1. Instrumentation the1979 publication of Currents in Subma- (Shepard et al., 1939; Emory and Hulsemann, rine Canyons and Other Sea Valleys by Fran- 1963; Ryan and Heezen 1965; Inman, 1970; Instrument development has come a long way cis Shepard and colleagues. Precise place- Drake and Gorsline, 1973; Shepard, 1975), this in the past 30 yr. The greatest leap in the tech- ments of high-resolution, high-frequency book was the fi rst of its kind to provide descrip- nology of fl ow measurements was the transition instruments have not only allowed research- tion and discussion on the various phenomena from mechanical to acoustic current meters. -
Odd-Eirik Heimsund
Numerical simulation of turbidity currents: a new perspective for small- and large- scale sedimentological experiments Snorre Heimsund Thesis for Candidatus Scientiarum degree in Sedimentology/Petroleum Geology Department of Earth Science University of Bergen 2007 i ABSTRACT Turbidity currents are a variety of subaqueous sediment-gravity flows, in which the suspension of sediment by water turbulence produces a water-sediment mixture that is denser than the ambient water and hence flows due to gravity along a topographic gradient. This type of sediment gravity flow is the most important mechanism for the dispersal and deposition of sand on deep-sea floors, as well as on the underwater slopes of many deltas and lakes. The hydrodynamics of turbidity currents are difficult to study in the natural environments, whereas laboratory experiments are limited to small-scale flows, time-consuming and not necessarily easier when it comes to the measuring of flow properties and establishing of the relationships between the turbulent flow structure and the transport and deposition of sediment. Mathematical models of turbidity current, integrated by computational fluid dynamics (CFD) and realized as numerical simulations, can be used to obviate these difficulties, and also to upscale laboratory datasets and to integrate the data from nature and experiments. The concept CFD refers to the numerical solution, by computational methods, of the governing equations describing fluid flow: the set of Navier-Stokes equations and the multi-phase fluid dynamics. CFD is widely used in the engineering branches of fluid mechanics, but is a relatively new numerical approach in the field of sedimentological research. In the present study, a three-dimensional model has been constructed by using the CFD software Flow-3D™ to simulate the flow of turbidity currents, including their internal hydraulic characteristics as well as sediment erosion and deposition. -
Seafloor Gravity Currents: Flow Dynamics in Overspilling And
Seafloor gravity currents: flow dynamics in overspilling and sinuous channels Robert William Kelly The University of Leeds School of Computing EPSRC Centre for Doctoral Training in Fluid Dynamics Submitted in accordance with the requirements for the degree of Doctor of Philosophy. October 2018 This copy has been supplied on the understanding that it is copyright material and that no quotation from the thesis may be published without proper acknowledgement. The candidate confirms that the work submitted is his/her/their own, except where work which has formed part of jointly authored publications has been included. The contribution of the candidate and the other authors to this work has been explicitly indicated below. The candidate confirms that appropriate credit has been given within the thesis where reference has been made to the work of others. A version of Chapter 5 has been accepted for publication in Journal of Geophysical Research: Oceans: “The structure and entrainment characteristics of partially-confined gravity currents”. Robert Kelly, Robert Dorrell, Alan Burns and William McCaffrey. Journal of Geophysical Research: Oceans. Under review. In this manuscript the work is the candidate’s own, with the other authors having acted in a supervisory role, providing feedback and suggestions. i “In every outthrust headland, in every curving beach, in every grain of sand there is the story of the earth.” – Rachel Carson ii Acknowledgements It feels a bit bizarre to finally be writing this, as it means my time as a PhD student must be drawing to a close. Firstly, I would like to thank my team of supervisors, Bill McCaffrey, Robert Dorrell and Alan Burns, who gave me their utmost support throughout this project. -
Turbidity and Wave Energy Affect Community Composition and Trophic Interactions
TURBIDITY AND WAVE ENERGY AFFECT COMMUNITY COMPOSITION AND TROPHIC INTERACTIONS A Dissertation by JESSICA LUNT BS, University of West Florida, 2008 Submitted in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY in MARINE BIOLOGY Texas A&M University-Corpus Christi Corpus Christi, Texas August 2014 © Jessica Heath Lunt All Rights Reserved August 2014 TURBIDITY AND WAVE ENERGY AFFECT COMMUNITY COMPOSITION AND TROPHIC INTERACTIONS A Dissertation by JESSICA LUNT This dissertation meets the standards for scope and quality of Texas A&M University-Corpus Christi and is hereby approved. Delbert L. Smee, PhD Thomas C. Shirley, PhD Chair Committee Member Michael S. Wetz, PhD Anna R. Armitage, PhD Committee Member Committee Member Anita J. Reed, PhD Graduate Faculty Representative JoAnn Canales, PhD Dean, College of Graduate Studies August 2014 ABSTRACT Abiotic variables are well known community regulators and can strongly influence species distributions when they are outside of a species physiological tolerance limits. However, environmental variables within tolerance limits may also alter species distributions, morphology, predator-prey interactions, and influence the structure and function of communities. The purpose of this study was to determine how abiotic variables (notably turbidity) alter diversity, species distributions and abundances, predation rates on and species morphology. Texas Parks and Wildlife Department Fisheries Independent Survey Data from 1991- 2008 were used in addition to field surveys of St. Charles Bay to determine the effects of turbidity on fish and crab diversity and abundance. Feeding assays were conducted in the field using groups of 5 mud crabs and 10 juvenile oysters to assess feeding rates in high and low turbidity. -
Direct and Indirect Impacts of Turbidity and Diet on an African Cichlid Fish
Living in a haze: Direct and indirect impacts of turbidity and diet on an African cichlid fish Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Tiffany Lynn Atkinson Graduate Program in Environment and Natural Resources The Ohio State University 2019 Thesis Committee Dr. Suzanne M. Gray, Advisor Dr. Lauren M. Pintor Dr. Roman P. Lanno Dr. Lauren J. Chapman Copyrighted by Tiffany Lynn Atkinson 2019 2 Abstract Worldwide, a major threat to aquatic systems is increased sediment runoff, which can lead to elevated levels of turbidity. In an increasingly variable world, the ability for animals to respond rapidly to environmental disturbance can be critical for survival. Chronic and acute turbidity exposure can have both indirect and direct effects on fish across large and small spatial scales. Indirect impacts include alteration of the sensory environment of fishes (disrupting communications) and shifts in prey availability; while direct impacts include damage to respiratory organs or eliciting physiological compensatory mechanisms that influence fitness- related traits associated with reproduction and survival. I used a combination of field and laboratory studies to examine the effects of elevated turbidity on an African cichlid fish (Pseudocrenilabrus multicolor victoriae). This sexually dimorphic species is widespread across the Nile River basin and is found across extreme environmental gradients (e.g. dissolved oxygen, turbidity). I investigated if within-population variation in diet and male nuptial coloration are associated with turbidity on a microgeographic spatial-scale. Diet was investigated because many cichlid fish depend on dietary carotenoids (red and yellow pigments) for their reproductive displays and other physiological mechanisms associated with health. -
Origin and Evolution Processes of Hybrid Event Beds in the Lower Cretaceous of the Lingshan Island, Eastern China
Australian Journal of Earth Sciences An International Geoscience Journal of the Geological Society of Australia ISSN: 0812-0099 (Print) 1440-0952 (Online) Journal homepage: http://www.tandfonline.com/loi/taje20 Origin and evolution processes of hybrid event beds in the Lower Cretaceous of the Lingshan Island, Eastern China T. Yang, Y. Cao, H. Friis, K. Liu & Y. Wang To cite this article: T. Yang, Y. Cao, H. Friis, K. Liu & Y. Wang (2018) Origin and evolution processes of hybrid event beds in the Lower Cretaceous of the Lingshan Island, Eastern China, Australian Journal of Earth Sciences, 65:4, 517-534, DOI: 10.1080/08120099.2018.1433236 To link to this article: https://doi.org/10.1080/08120099.2018.1433236 Published online: 16 May 2018. Submit your article to this journal Article views: 9 View related articles View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=taje20 AUSTRALIAN JOURNAL OF EARTH SCIENCES, 2018 VOL. 65, NO. 4, 517–534 https://doi.org/10.1080/08120099.2018.1433236 Origin and evolution processes of hybrid event beds in the Lower Cretaceous of the Lingshan Island, Eastern China T. Yang a,b,c, Y. Cao a, H. Friisc, K. Liu a and Y. Wanga aSchool of Geosciences, China University of Petroleum, Qingdao, 266580, PR China; bShandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals, Shandong University of Science and Technology, Qingdao 266580, Shandong, PR China; cDepartment of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, DK-8000 Aarhus C, Denmark ABSTRACT ARTICLE HISTORY On the basis of detailed sedimentological investigation, three types of hybrid event beds (HEBs) Received 13 September 2017 together with debrites and turbidites were distinguished in the Lower Cretaceous sedimentary Accepted 15 January 2018 – sequence on the Lingshan Island in the Yellow Sea, China. -
Chapter 3—Relative Risks to the Great Barrier Reef from Degraded Water Quality
Scientific Consensus Statement 2013 – Chapter 3 ©The State of Queensland 2013. Published by the Reef Water Quality Protection Plan Secretariat, July 2013. Copyright protects this publication. Excerpts may be reproduced with acknowledgement to the State of Queensland. Image credits: TropWATER James Cook University, Tourism Queensland. This document was prepared by an independent panel of scientists with expertise in Great Barrier Reef water quality. This document does not represent government policy. 2 Relative risks to the Great Barrier Reef from degraded water quality Scientific Consensus Statement 2013 – Chapter 3 Table of Contents Executive summary .......................................................................................................................... 4 Introduction ..................................................................................................................................... 6 Synthesis process ............................................................................................................................. 7 Previous Consensus Statement findings ........................................................................................ 19 Current evidence on the relative risks of water quality pollutants to the Great Barrier Reef ...... 21 What is the current relative risk of priority pollutants to Great Barrier Reef marine systems? .............. 21 Where are the risks highest or the benefits of improved management greatest? .................................. 26 When are the risks