DOCSLIB.ORG

The Concept of Transport Capacity in Geomorphology

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Concept of Transport Capacity in Geomorphology 1 2 3 4 The Concept of Transport Capacity 5 in Geomorphology 6 7 8 John Wainwright, 9 Durham University, Department of Geography, Science Laboratories, South Road, 10 Durham, DH1 3LE, UK ([email protected]) 11 12 Anthony J Parsons 13 Department of Geography, University of Sheffield, Winter Street, Sheffield S10 2TN, 14 UK ([email protected]) 15 16 James R Cooper 17 Department of Geography and Planning, School of Environmental Sciences, 18 University of Liverpool, Liverpool L69 7ZT, UK ([email protected]) 19 20 Peng Gao, 21 Department of Geography, SUNY Syracuse, 144 Eggers Hall, Syracuse, New York 22 13244, USA ([email protected]) 23 24 John A Gillies, 25 Division of Atmospheric Sciences, Desert Research Institute, 2215 Raggio Parkway, 26 Reno, NV 89512, USA ([email protected]) 27 28 Luca Mao, 29 Department of Ecosystems and Environment, Pontificia Universidad Católica de 30 Chile, Avenida Vicuña Mackenna 4860, Santiago de Chile, Chile ([email protected]) 31 32 Julian D Orford 33 School of Geography, Archaeology and Palaeoecology, Queen’s University Belfast, 34 Belfast, BT7 1NN, Northern Ireland, UK ([email protected]) 35 36 Peter G Knight 37 School of Physical and Geographical Sciences 38 William Smith Building, Keele University, ST5 5BG. UK ([email protected]) 39 40 Abstract 41 The concept of sediment-transport capacity has been engrained in geomorphological literature 42 for >50 years, although the earliest explicit definition is Gilbert’s work in fluvial 43 geomorphology in the 1870s with implicit versions found in 18th - 19th century engineering. 44 We review the development of transport capacity in the fluvial, aeolian, coastal, hillslope, 45 débris flow and glacial process domains. Despite cross-fertilization between different process 46 domains, there seem to have been independent inventions of the idea in aeolian and hillslope 47 geomorphology. We demonstrate how different definitions have been used, which makes it 48 both a difficult concept to test, and one that may lead to poor communications between those 49 working in different domains. 50 The original relation between the power of a flow and its ability to transport sediment 51 can be challenged for three reasons. First, as sediment becomes entrained in a flow, the nature 52 of the flow changes and so it is unreasonable to link the capacity of the water or wind only to 53 the ability of the fluid to move sediment. Secondly, the range of processes involved in most 54 movements means that simple relations are unlikely to hold, not least because the movement 55 of sediment often changes the substrate, which in turn affects the flow conditions. Thirdly, the 56 inherently stochastic nature of sediment transport means that any capacity relationships do not 57 scale either in time or in space. Consequently, new theories of sediment transport are needed 58 to improve understanding and prediction, and guide measurement and management of all 59 geomorphic systems. 60 61 Keywords: sediment transport; geomorphology; turbulence; complex systems; models; 62 management 1 63 Introduction 64 The notion of sediment-transport capacity has been engrained in geomorphological and related 65 geophysical literature for over 50 years. However, the definition has not always been 66 consistent across the discipline. One reason for this inconsistency has been the tendency in 67 recent decades for increasing specialization in studies relating to particular process domains. 68 Together with the proliferation of literature, specialization means that only rarely are 69 evaluations made of linkages between concepts in different process domains. This trend 70 towards increasingly focussed specialization, however, contrasts with developments in 71 complexity theory, Earth-Systems Science and integrated management of the environment that 72 all emphasize the benefits of integrated approaches. In this review, we will first examine how 73 the notion of transport capacity has been developed and applied in the various branches of 74 geomorphology in order to evaluate commonalities and divergences in approach, in relation to 75 conceptual developments and empirical support. In doing so, we assess the effectiveness of 76 the concept by using advances across the different process domains to inform and interpret 77 each other and thereby provide an overall critique of the concept. We take a critical realist 78 approach (Richards, 1990; Sayer, 2000) to assess whether the use of the concept, both within 79 a single process domain and between different process domains, enables the explanation of 80 observations both in the field and laboratory. In other words, if the definitions of transport 81 capacity that have been developed are real – mechanistic – characterizations of how sediment 82 is transported in geomorphic systems, they should be able to explain observed phenomena. If 83 not, there needs to be a reëvluation of whether it is the concept (or concepts) that are 84 problematic, or the experimental approaches and data that are flawed. 85 86 GK Gilbert was central to the development of the concept of transport capacity in 87 geomorphology. In his Report on the Geology of the Henry Mountains [1877] he noted: 88 89 Transportation is favored by increasing water supply as greatly as by increasing 90 declivity. When the volume of a storm increases, it becomes at the same time more 91 rapid, and its transporting capacity gains by the increment to velocity as by the 92 increment to volume. Hence the increase in power of transportation is more than 93 proportional to the increase in volume. 94 [Gilbert 1877: 98] 95 2 96 Based on a steady-state conceptualization of river form, and an early formulation of a concept 97 of stream power, he goes on to suggest: 98 99 Let us suppose that a stream endowed with a constant volume of water, is at some 100 point continuously supplied with as great a load as it is capable of carrying. For so 101 great a distance as its velocity remains the same, it will neither corrade (downward) 102 nor deposit, but will leave the grade of its bed unchanged. But if in its progress it 103 reaches a place where a less declivity of bed gives a diminished velocity, its 104 capacity for transportation will become less than the load and part of the load will 105 be deposited. Or if in its progress it reaches a place where a greater declivity of bed 106 gives an increased velocity, the capacity for transportation will become greater than 107 the load and there will be corrasion of the bed. In this way a stream which has a 108 supply of débris equal to its capacity, tends to build up the gentler slopes of its bed 109 and cut away the steeper. It tends to establish a single, uniform grade. 110 [Gilbert 1877: 106] 111 112 Implicit in this definition is the idea of supply limitation, that a channel will convey as much 113 sediment as its capacity allows, unless there is insufficient material to be transported. More 114 widely influential was Gilbert’s seminal USGS Professional Paper The Transportation of 115 Débris by Running Water, published in 1914. It is this work that seems to provide the first 116 formal definition of transport capacity in the English literature: 117 118 The maximum load a stream can carry is its capacity. ... Capacity is a function of 119 various conditions, such as slope and discharge, .... When a fully loaded stream 120 undergoes some change of condition affecting its capacity, it becomes thereby 121 overloaded or underloaded. If overloaded, it drops part of its load, making a 122 deposit. If underloaded, it takes on more load, thereby eroding its bed. 123 [Gilbert 1914: 35] 124 125 He goes on to say that capacity is a function of discharge, slope, débris size and channel-form 126 (channel depth / width) ratio. While the concept of transport capacity is asserted without 127 support from further reference in the 1877 report, his statement that “the maximum particles 128 which streams are able to move are proportioned to the sixth powers of their velocities” 3 129 [Gilbert, 1877: 104] shows that he was at least aware of the work of Leslie [1823] or more 130 likely Hopkins [1844] on entrainment by this time. In 1914, however, Gilbert suggests that the 131 idea can be traced at least as far back as 1786 in the work of Dubuat, who demonstrated 132 experimentally that the sediment discharge in a water flow was proportional to a square of 133 excess velocity (flow velocity minus the flow velocity required for entrainment). These results 134 were certainly still in use almost a century later, for example in the study of Lechalas [1871]. 135 Both of these authors were working in a tradition of applied hydraulics, interested in the 136 navigation of rivers and the building of canals. 137 138 Although Gilbert [1877, 1914] provides the first uses of the term in the 139 geomorphological/geophysical literature, it was largely ignored or misunderstood by this 140 community until championed by Strahler’s advocacy of a process-based geomorphology in his 141 papers of the early 1950s [1950, 1952] (see, for example, Holmes’ review of 1915 in which he 142 suggests the wide variability in observed rates mean that these sorts of observation are unlikely 143 to be useful in dating geological deposits and thus unlikely to be of broader use. But, by contrast 144 that “experiments of these kinds, while of considerable theoretical interest, serve only as a 145 check to undue speculation” [1915: 134] and what is needed is more field study). However, 146 the engineering aspects of his work meant that Gilbert influenced the hydraulic engineering 147 literature more directly, for example being cited in the work of Hans Einstein [1942: 567], 148 originally working in the Zürich school, but then later for the US Department of Agriculture 149 (e.g., Meyer-Peter et al.
Load more

Recommended publications
  • Geomorphic Classification of Rivers
    9.36 Geomorphic Classification of Rivers JM Buffington, U.S. Forest Service, Boise, ID, USA DR Montgomery, University of Washington, Seattle, WA, USA Published by Elsevier Inc. 9.36.1 Introduction 730 9.36.2 Purpose of Classification 730 9.36.3 Types of Channel Classification 731 9.36.3.1 Stream Order 731 9.36.3.2 Process Domains 732 9.36.3.3 Channel Pattern 732 9.36.3.4 Channel–Floodplain Interactions 735 9.36.3.5 Bed Material and Mobility 737 9.36.3.6 Channel Units 739 9.36.3.7 Hierarchical Classifications 739 9.36.3.8 Statistical Classifications 745 9.36.4 Use and Compatibility of Channel Classifications 745 9.36.5 The Rise and Fall of Classifications: Why Are Some Channel Classifications More Used Than Others? 747 9.36.6 Future Needs and Directions 753 9.36.6.1 Standardization and Sample Size 753 9.36.6.2 Remote Sensing 754 9.36.7 Conclusion 755 Acknowledgements 756 References 756 Appendix 762 9.36.1 Introduction 9.36.2 Purpose of Classification Over the last several decades, environmental legislation and a A basic tenet in geomorphology is that ‘form implies process.’As growing awareness of historical human disturbance to rivers such, numerous geomorphic classifications have been de- worldwide (Schumm, 1977; Collins et al., 2003; Surian and veloped for landscapes (Davis, 1899), hillslopes (Varnes, 1958), Rinaldi, 2003; Nilsson et al., 2005; Chin, 2006; Walter and and rivers (Section 9.36.3). The form–process paradigm is a Merritts, 2008) have fostered unprecedented collaboration potentially powerful tool for conducting quantitative geo- among scientists, land managers, and stakeholders to better morphic investigations.
    [Show full text]
  • 3.5.3 the Use of Erosion Pins in Geomorphology
    © Author(s) 2016. CC Attribution 4.0 License. ISSN 2047 - 0371 3.5.3 The use of erosion pins in geomorphology John Boardman1,2 and David Favis-Mortlock1 1Environmental Change Institute, Oxford University Centre for the Environment, Oxford, UK ([email protected]) 2Department of Environmental and Geographical Science, University of Cape Town, South Africa ABSTRACT: Erosion pins have been widely used in geomorphology since the 1950s to estimate rates of change (erosion and – less commonly – accumulation) in land surfaces. They may be used for short- and long-term surveys and are quick and easy to install and measure. Erosion pins are particularly suited to bare, undisturbed environments such as badlands and sand dunes. Our recommendations for their use follow those of Haigh (1977) and Lawler (1993) but we also discuss the need for researchers to be aware of issues which arise from of measurement error, particularly for short-term studies and analytical methods which rely on few pin measurements. There is also a not inconsiderable challenge involved in extrapolating results derived from erosion pin measurements to larger areas. KEYWORDS: badlands, erosion pins, erosion rates, measurement errors erosion pins is not necessary: useful data can Introduction be collected with occasional visits. The basic idea behind the use of erosion pins However, this simplicity is deceptive. to quantify land-surface change is very Considerations of pin siting, measurement straightforward. A rod is firmly fixed into the error, and interpretation of results rapidly ground (or other substrate), and a note made introduce additional complexity. Thus, any of the length of rod which remains exposed.
    [Show full text]
  • Part 629 – Glossary of Landform and Geologic Terms
    Title 430 – National Soil Survey Handbook Part 629 – Glossary of Landform and Geologic Terms Subpart A – General Information 629.0 Definition and Purpose This glossary provides the NCSS soil survey program, soil scientists, and natural resource specialists with landform, geologic, and related terms and their definitions to— (1) Improve soil landscape description with a standard, single source landform and geologic glossary. (2) Enhance geomorphic content and clarity of soil map unit descriptions by use of accurate, defined terms. (3) Establish consistent geomorphic term usage in soil science and the National Cooperative Soil Survey (NCSS). (4) Provide standard geomorphic definitions for databases and soil survey technical publications. (5) Train soil scientists and related professionals in soils as landscape and geomorphic entities. 629.1 Responsibilities This glossary serves as the official NCSS reference for landform, geologic, and related terms. The staff of the National Soil Survey Center, located in Lincoln, NE, is responsible for maintaining and updating this glossary. Soil Science Division staff and NCSS participants are encouraged to propose additions and changes to the glossary for use in pedon descriptions, soil map unit descriptions, and soil survey publications. The Glossary of Geology (GG, 2005) serves as a major source for many glossary terms. The American Geologic Institute (AGI) granted the USDA Natural Resources Conservation Service (formerly the Soil Conservation Service) permission (in letters dated September 11, 1985, and September 22, 1993) to use existing definitions. Sources of, and modifications to, original definitions are explained immediately below. 629.2 Definitions A. Reference Codes Sources from which definitions were taken, whole or in part, are identified by a code (e.g., GG) following each definition.
    [Show full text]
  • Glacial Geomorphology☆ John Menzies, Brock University, St
    Glacial Geomorphology☆ John Menzies, Brock University, St. Catharines, ON, Canada © 2018 Elsevier Inc. All rights reserved. This is an update of H. French and J. Harbor, 8.1 The Development and History of Glacial and Periglacial Geomorphology, In Treatise on Geomorphology, edited by John F. Shroder, Academic Press, San Diego, 2013. Introduction 1 Glacial Landscapes 3 Advances and Paradigm Shifts 3 Glacial Erosion—Processes 7 Glacial Transport—Processes 10 Glacial Deposition—Processes 10 “Linkages” Within Glacial Geomorphology 10 Future Prospects 11 References 11 Further Reading 16 Introduction The scientific study of glacial processes and landforms formed in front of, beneath and along the margins of valley glaciers, ice sheets and other ice masses on the Earth’s surface, both on land and in ocean basins, constitutes glacial geomorphology. The processes include understanding how ice masses move, erode, transport and deposit sediment. The landforms, developed and shaped by glaciation, supply topographic, morphologic and sedimentologic knowledge regarding these glacial processes. Likewise, glacial geomorphology studies all aspects of the mapped and interpreted effects of glaciation both modern and past on the Earth’s landscapes. The influence of glaciations is only too visible in those landscapes of the world only recently glaciated in the recent past and during the Quaternary. The impact on people living and working in those once glaciated environments is enormous in terms, for example, of groundwater resources, building materials and agriculture. The cities of Glasgow and Boston, their distinctive street patterns and numerable small hills (drumlins) attest to the effect of Quaternary glaciations on urban development and planning. It is problematic to precisely determine when the concept of glaciation first developed.
    [Show full text]
  • Forensic Geoscience: Applications of Geology, Geomorphology and Geophysics to Criminal Investigations
    Forensic Geoscience: applications of geology, geomorphology and geophysics to criminal investigations Ruffell, A., & McKinley, J. (2005). Forensic Geoscience: applications of geology, geomorphology and geophysics to criminal investigations. Earth-Science Reviews, 69(3-4)(3-4), 235-247. https://doi.org/10.1016/j.earscirev.2004.08.002 Published in: Earth-Science Reviews Queen's University Belfast - Research Portal: Link to publication record in Queen's University Belfast Research Portal General rights Copyright for the publications made accessible via the Queen's University Belfast Research Portal is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The Research Portal is Queen's institutional repository that provides access to Queen's research output. Every effort has been made to ensure that content in the Research Portal does not infringe any person's rights, or applicable UK laws. If you discover content in the Research Portal that you believe breaches copyright or violates any law, please contact [email protected]. Download date:26. Sep. 2021 Earth-Science Reviews 69 (2005) 235–247 www.elsevier.com/locate/earscirev Forensic geoscience: applications of geology, geomorphology and geophysics to criminal investigations Alastair Ruffell*, Jennifer McKinley School of Geography, Queen’s University, Belfast, BT7 1NN, N. Ireland Received 12 January 2004; accepted 24 August 2004 Abstract One hundred years ago Georg Popp became the first scientist to present in court a case where the geological makeup of soils was used to secure a criminal conviction.
    [Show full text]
  • 2 Observation in Geomorphology
    2 Observation in Geomorphology Bruce L. Rhoads and Colin E. Thorn Department of Geography, University of Illinois at Urbana-Champaign ABSTRACT Observation traditionally has occupied a central position in geomorphologic research. The prevailing, tacit attitude of geomorphologists toward observation appears to be consistent with radical empiricism. This attitude stems from a strong historical emphasis on the value of fieldwork in geomorphology, which has cultivated an aesthetic for letting the data speak for themselves, and from cursory and exclusive exposure of many geomorphologists to empiricist philosophical doctrines, especially logical positivism. It is, by and large, also an unexamined point of view. This chapter provides a review of contemporary philosophical perspectives on scientific observation. This discussion is then used as a filter or lens through which to view the epistemic character and role of observation in geomorphology. Analysis reveals that whereas G.K. Gilbert's theory-laden approach to observation preserved scientific objectivity, the extreme theory-ladenness of W.M. Davis's observational procedures often resulted in considerable subjectivity. Contemporary approaches to observation in geomorphology are shown to conform broadly with the model provided by Gilbert. The hallmark of objectivity in geomorphology is the assurance of data reliability through the introduction of fixed rule-based procedures for obtaining information. INTRODUCTION Geomorphologists traditionally have assigned great virtue to observation. The venerated status of observation can be traced to the origin of geomorphology as a field science in the late 1800s. Exploration of sparsely vegetated landscapes in the American West by New- berry, Powell, Hayden, Gilbert, and others inspired perceptive insights about landscape dynamics that provided a foundation for the discipline (Baker and Twidale 1991).
    [Show full text]
  • 4-Year Phd Fellow Position in Geomorphology/Paleoclimatology
    4-year PhD fellow position in Geomorphology/Paleoclimatology (2017-2021) Contrato predoctoral (4 años) para la formación de doctores en Geomorfología/Paleoclimatología FluvPaleoRisk Project. 3000 years of flooding in mountain catchments: connectivity, synchronization or teleconnection? (CGL2016-75475-R) The variation of surface hydrological conditions that determine the pattern of river systems, affects significantly environmental and socioeconomic systems and flood risk. The project develops a multidisciplinary approach that contributes to the generation of long series of paleofloods in the Eastern Betic Range and Western Alps, that record also low-frequency extreme events. The approach analyzes fluvial sedimentary and lichenometric proxies, as well as instrumental data and documentary sources by applying geostatistical methods, climate modeling and remote sensing. The control mechanisms and forcings (orbital, solar, climate, volcanic, land use changes, geomorphological and hydrological dynamics) involved in fluvial processes of basins with diferent features (altitude, surface) will be analyzed. The study aims to determine whether paleofloods can be attributed to warm or cool climate periods, higher or lower humidity, and to regional-scale synoptic situations. Furthermore, it investigates whether there is a synchronous or asynchronous response between basins such as differences of catchment connectivity, and if the altitude is a key factor because of the snow melt. The analysis of atmospheric circulation modes that have produced periods
    [Show full text]
  • A Geomorphic Classification System
    A Geomorphic Classification System U.S.D.A. Forest Service Geomorphology Working Group Haskins, Donald M.1, Correll, Cynthia S.2, Foster, Richard A.3, Chatoian, John M.4, Fincher, James M.5, Strenger, Steven 6, Keys, James E. Jr.7, Maxwell, James R.8 and King, Thomas 9 February 1998 Version 1.4 1 Forest Geologist, Shasta-Trinity National Forests, Pacific Southwest Region, Redding, CA; 2 Soil Scientist, Range Staff, Washington Office, Prineville, OR; 3 Area Soil Scientist, Chatham Area, Tongass National Forest, Alaska Region, Sitka, AK; 4 Regional Geologist, Pacific Southwest Region, San Francisco, CA; 5 Integrated Resource Inventory Program Manager, Alaska Region, Juneau, AK; 6 Supervisory Soil Scientist, Southwest Region, Albuquerque, NM; 7 Interagency Liaison for Washington Office ECOMAP Group, Southern Region, Atlanta, GA; 8 Water Program Leader, Rocky Mountain Region, Golden, CO; and 9 Geology Program Manager, Washington Office, Washington, DC. A Geomorphic Classification System 1 Table of Contents Abstract .......................................................................................................................................... 5 I. INTRODUCTION................................................................................................................. 6 History of Classification Efforts in the Forest Service ............................................................... 6 History of Development .............................................................................................................. 7 Goals
    [Show full text]
  • Precambrian Plate Tectonics: Criteria and Evidence
    VOL.. 16,16, No.No. 77 A PublicAtioN of the GeoloGicicAl Society of America JulyJuly 20062006 Precambrian Plate Tectonics: Criteria and Evidence Inside: 2006 Medal and Award Recipients, p. 12 2006 GSA Fellows Elected, p. 13 2006 GSA Research Grant Recipients, p. 18 Call for Geological Papers, 2007 Section Meetings, p. 30 Volume 16, Number 7 July 2006 cover: Magnetic anomaly map of part of Western Australia, showing crustal blocks of different age and distinct structural trends, juxtaposed against one another across major structural deformation zones. All of the features on this map are GSA TODAY publishes news and information for more than Precambrian in age and demonstrate that plate tectonics 20,000 GSA members and subscribing libraries. GSA Today was in operation in the Precambrian. Image copyright the lead science articles should present the results of exciting new government of Western Australia. Compiled by Geoscience research or summarize and synthesize important problems Australia, image processing by J. Watt, 2006, Geological or issues, and they must be understandable to all in the earth science community. Submit manuscripts to science Survey of Western Australia. See “Precambrian plate tectonics: editors Keith A. Howard, [email protected], or Gerald M. Criteria and evidence” by Peter A. Cawood, Alfred Kröner, Ross, [email protected]. and Sergei Pisarevsky, p. 4–11. GSA TODAY (ISSN 1052-5173 USPS 0456-530) is published 11 times per year, monthly, with a combined April/May issue, by The Geological Society of America, Inc., with offices at 3300 Penrose Place, Boulder, Colorado. Mailing address: P.O. Box 9140, Boulder, CO 80301-9140, USA.
    [Show full text]
  • Geomorphology
    GEOMORPHOLOGY AUTHOR INFORMATION PACK TABLE OF CONTENTS XXX . • Description p.1 • Audience p.1 • Impact Factor p.1 • Abstracting and Indexing p.2 • Editorial Board p.2 • Guide for Authors p.4 ISSN: 0169-555X DESCRIPTION . Geomorphology publishes peer-reviewed works across the full spectrum of the discipline from fundamental theory and science to applied research of relevance to sustainable management of the environment. Our journal's scope includes geomorphic themes of: tectonics and regional structure; glacial processes and landforms; fluvial sequences, Quaternary environmental change and dating; fluvial processes and landforms; mass movement, slopes and periglacial processes; hillslopes and soil erosion; weathering, karst and soils; aeolian processes and landforms, coastal dunes and arid environments; coastal and marine processes, estuaries and lakes; modelling, theoretical and quantitative geomorphology; DEM, GIS and remote sensing methods and applications; hazards, applied and planetary geomorphology; and volcanics. Benefits to authors We also provide many author benefits, such as free PDFs, a liberal copyright policy, special discounts on Elsevier publications and much more. Please click here for more information on our author services. Please see our Guide for Authors for information on article submission. If you require any further information or help, please visit our Support Center AUDIENCE . Geomorphologists, Physical Geographers, Engineering Geologists and Exploration Geologists. IMPACT FACTOR . 2020: 4.139 © Clarivate Analytics
    [Show full text]
  • Glaciology and Glacio-Geomorphology in Victoria Landand Queen Maud Mountains Paul Andrew Mayewski University of Maine, [email protected]
    The University of Maine DigitalCommons@UMaine Earth Science Faculty Scholarship Earth Sciences 1979 Glaciology and Glacio-geomorphology in Victoria Landand Queen Maud Mountains Paul Andrew Mayewski University of Maine, [email protected] Follow this and additional works at: https://digitalcommons.library.umaine.edu/ers_facpub Part of the Geomorphology Commons, Glaciology Commons, and the Hydrology Commons Repository Citation Mayewski, Paul Andrew, "Glaciology and Glacio-geomorphology in Victoria Landand Queen Maud Mountains" (1979). Earth Science Faculty Scholarship. 219. https://digitalcommons.library.umaine.edu/ers_facpub/219 This Article is brought to you for free and open access by DigitalCommons@UMaine. It has been accepted for inclusion in Earth Science Faculty Scholarship by an authorized administrator of DigitalCommons@UMaine. For more information, please contact [email protected]. The source of these clasts has not yet been deter- tact delta at the eastern end of Lake Vida, as well as mined. However, given the broad distribution of vol- algae from within the delta. When subjected to radio- canic clasts and the apparent lack of volcanic vents (as carbon analysis, these samples should indicate the age determined by the field partys reconnaissance of ex- of one of the several terminal positions of the Victoria posed bedrock areas, especially those adjacent to and Lower Glacier, assuming that the age of the samples lies east of the Victoria Lower Glacier), the clasts were most within the range of the dating method. probably derived from the Ross Sea floor to the east and This research was supported by National Science then transported into the valley by glacier ice moving Foundation grant DPP 76-23460.
    [Show full text]
  • The Geomorphology of the Makran Trench in the Context of the Geological and Geophysical Settings of the Arabian Sea Polina Lemenkova
    The geomorphology of the Makran Trench in the context of the geological and geophysical settings of the Arabian Sea Polina Lemenkova To cite this version: Polina Lemenkova. The geomorphology of the Makran Trench in the context of the geological and geophysical settings of the Arabian Sea. Geology, Geophysics & Environment, 2020, 46 (3), pp.205- 222. 10.7494/geol.2020.46.3.205. hal-02999997 HAL Id: hal-02999997 https://hal.archives-ouvertes.fr/hal-02999997 Submitted on 11 Nov 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License 2020, vol. 46 (3): 205–222 The geomorphology of the Makran Trench in the context of the geological and geophysical settings of the Arabian Sea Polina Lemenkova Analytical Center; Moscow, 115035, Russian Federation; e-mail: [email protected]; ORCID ID: 0000-0002-5759-1089 © 2020 Author. This is an open access publication, which can be used, distributed and reproduced in any medium according to the Creative Commons CC-BY 4.0 License requiring that the original work has been properly cited. Received: 10 June 2020; accepted: 1 October 2020; first published online: 27 October 2020 Abstract: The study focuses on the Makran Trench in the Arabian Sea basin, in the north Indian Ocean.
    [Show full text]