GLACIATED CONTINENTAL MARGINS An Atlas of Acoustic Images GLACIATED CONTINENTAL MARGINS An Atlas of Acoustic Images EDITED BY Thomas A. Davies, Trevor Bell, Alan K. Cooper, Heiner Josenhans, Leonid Polyak, Anders Solheim, Martyn S. Stoker, Jay A. Stravers CHAPMAN & HALL London· Weinheim . New York · Tokyo · Melbourne· Madras Published by Chapman & HaIl, 2-6 Boundary Row, London SEt 8HN, UK Chapman & Hall, 2--6 Boundary Row, London SEI 8HN, UK Chapman & Hall GmbH, Pappelallee 3, 69469 Weinheim, Germany Chapman & Hall USA, 115 Fifth Avenue, New York, NY lOoo3, USA Chapman & Hall Japan, ITP-Japan, Kyowa Building, 3F, 2-2-1 Hirakawacho, Chiyoda-ku, Tokyo 102, Japan Chapman & Hall Australia, 102 Dodds Street, South Melbourne, Victoria 3205, Australia Chapman & Hall India, R. Seshadri, 32 Second Main Road, CIT East, Madras 6oo 035, India First edition 1997 © 1997 Chapman & Hall ISBN 0412793407 lllustrations Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the UK Copyright Designs and Patents Act, 1988, this publication may not be reproduced, stored, or transmitted, in any form or by Frontispiece: The west coast of Svalbard in early any means, without the prior permission in writing of the publishers, or in the case of reprographic reproduction only in summer. (Photograph by Thomas A. Davies) accordance with the terms of the licences issued by the Copyright Licensing Agency in the UK, or in accordance with the terms of licences issued by the appropriate Reproduction Rights Organization outside the UK. Enquiries concerning repro duction outside the terms stated here should be sent to the publishers at the London address printed on this page. Front cover: Larsen Ice Shelf, West Antarctica. The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in (Photograph by Lawrence A. Lawver) this book and cannot accept any legal responsibility or liability for any errors or omissions that may be made. Back cover: Sirnrad EM 100 multibearn bathymetry showing an ice terminal, morainal A catalogue record for this book is available from the British Library bank at the northern end of Emerald Basin on the eastern Canadian continental shelf. The area of seafloor shown is about 5 km wide, with water depths deepening from about 150 m at the ridged, iceberg scoured moraine (white) to about 230 m at the flat lying, pockmarked surface of Holocene clay (green). The pockmarks are likely formed by escaping gas from biogenic or petrogenic origin. (Graphic prepared by Robert Courtney, I§ Printed on permanent acid-free text paper, manufactured in accordance with Geological Survey of Canada (Atlantic). ANSIINISO Z39.48-1992 and ANSIINISO Z39.48-1984 (Permanence of Paper). TABLE OF CONTENTS List of Contributors XVll Editorial Committee Xll Acknowledgements XVlll INTRODUCTION 1 Thomas A. Davies PART ONE SEISMIC CHARACTER AND VARIABILITY 7 Seismic Methods and Interpretation 9 Martyn S. Stoker, Jack B. Pheasant, Heiner Josenhans Iceberg Scours: Records from Broad and Narrow-Beam Acoustic Systems 27 Julian A. Dowdeswell, Robert J. Whittington, Heinrich Villinger 29 Effects of Shallow Gas on Seismic Reflection Profiles Gordon B.J. Fader Simultaneous use of Multiple Seismic Reflection Systems for High Resolution and Deep Penetration 31 Heiner Josenhans PART TWO FEATURES FOUND IN GLACIMARINE ENVIRONMENTS 33 1 Subglacial Features 34 Overview 34 Alan K Cooper, Paul R Carlson, Erk Reimnitz A Glacial Trough Eroded in Layered Sediments in a Norwegian Fjord 36 DagOttesen Structures in Scorseby Sund, East Greenland 38 Gabriele Uenzelmann-Neben Glacially Overdeepened Troughs and Ice Retreat "Till Tongue" Deposits in Queen Charlotte Sound, British Columbia, Canada 40 Heiner Josenhans v Glacial Erosion of Sediments in the Alfjord, Western Norway 42 Inge Aarseth Glacial Unconfonnities on the Antarctic Continental Margin, an Example from the Antarctic Peninsula 43 Philip J. Bart, John B. Anderson Glacial Sole Markings on Bedrock and Till in Hudson Bay, Canada 46 Heiner Josenhans Drumlins in Lake Ontario 48 c.F. Michael Lewis, Larry A. Mayer, Gordon D.M Cameron, Brian J. Todd A Seabed Drumlin Field on the Inner Scotian Shelf, Canada 50 Gordon B. J. Fader, Rudolph R Stea, R C. Courtney Drumlin Field on the Ross Sea Continental Shelf, Antarctica 52 Stephanie Shipp, John B. Anderson Lineations on the Ross Sea Continental Shelf, Antarctica 54 Stephanie Shipp, John B. Anderson Submarine Glacial Flutes and DeGeer Moraines 56 Anders Solheim Glacial Flutes and Iceberg Furrows, Antarctic Peninsula 58 Carol J. Pudsey, Peter F. Barker, Robert D. Larter Subglacial Features Interpreted from 3D-Seismic 60 Tor Helge Lygren, Mona Nyland Berg, Kjell Berg Subglacial Channels in Hudson Bay, Canada 62 Heiner Josenhans Subglacial Channels, Southern Barents Sea 64 Valery Gataullin, Leonid Polyak Buried Sub-and Proglacial Channels: 3D-Seismic Morphostratigraphy 66 Daniel Praeg, David Long Buried Tunnel-Valleys: 3D-Seismic Morphostratigraphy 68 Daniel Praeg Glaciotectonic Features, Southeastern Barents Sea 70 Valery Gataullin, Leonid Polyak Glacial Tectonism and Defonnation of Marine Sediments in the Central Chilean Fjords 72 Jay A. StraYers vi 2 Ice-marginal and Ice-Contact Features 75 Overview 75 Anders Solheim Younger Dryas Moraines in the Nordfjord, the Norddalsfjord and the Dalsfjord, Western Norway 77 Inge Aarseth Ice-contact Deposits in Fjords from Northern Norway 80 Astrid Lysa, Tore 0. Vorren Morainic Ridge Complex, Eastern Barents Sea 82 Valery Gataullin, Leonid Polyak Submarine End-Moraines on the West Shetland Shelf, North-West Britain 84 Martyn S. Stoker Submarine Lateral Moraine in the South Central Region of Hudson Strait, Canada 86 Brian MacLean Thick Multiple Ice-contact Deposits Adjoining the Sill at the Entrance to Hudson Strait, Canada 88 Brian MacLean Lobate Stacked Moraines: Lake Melville, Labrador 90 James P. Syvitski Muir Inlet Morainal Bank Complex, Glacier Bay, S.E. Alaska 92 Keith C. Seramur, Ross D. Powell, Paul R Carlson, Ellen A. Cowan A Late Glacial Readvance Moraine in the Central Chilean Fjords 94 Jay A. StraYers, John B. Anderson Grounding Zone Wedges on the Antarctic Continental Shelf, Antarctic Peninsula 96 Philip J. Bart, John B. Anderson Grounding Zone Wedges on the Antarctic Continental Shelf, Weddell Sea 98 John B. Anderson Grounding Zone and Associated Proglacial Seismic Facies from Bransfield Basin, Antarctica 100 Laura A. Banfield, John B. Anderson Grounding Zone Wedges on the Antarctic Continental Shelf, Ross Sea 104 Stephanie Shipp, John B. Anderson Paleo-ice Streams and Ice Stream Boundaries, Ross Sea, Antarctica 106 Stephanie Shipp, John B. Anderson Glaciomarine Deposits on the Continental Shelf of the Ross Sea, Antarctica 110 Laura De Santis, John B. Anderson, Giuliano Brancolini, Igor Zayatz Vll 3 Debris Flows and Slumps 115 Overview 115 Jay A. StraYers Submarine Debris Flows on Glacier-Influenced Margins: GLORIA Imagery of the Bear Island Fan 118 Julian A. Dowdeswell, Neil H. Kenyon, Jan Sverre Laberg, Anders Elverhei Glacigenic Mudflows on the Bear Island Trough Mouth Fan 120 Kathleen Crane, Peter R. Vogt, Eirik Sundvor Debris Flow Deposits on a Glacier-Fed Submarine Fan off the Western Barents Sea Continental Shelf 122 Jan Sverre Laberg, Tore O. Vorren Debris Flows on a Glacial Trough Mouth Fan, Norwegian Channel and North Sea Fan 124 Edward L. King Submarine Debris Flows on a Glacially-Influenced Basin Plain, Faeroe-Shetland Channel 126 Martyn S. Stoker A Cross-Section of a Fjord Debris Flow, East Greenland 128 Robert J. Whittington, Frank Niessen Synsedimentary Faulting in an East Greenland Fjord 130 Frank Niessen, Robert J. Whittington Staircase Rotational Slides in an Ice-proximal Fjord Setting, East Greenland 132 Robert J. Whittington, Frank Niessen Glacially-influenced Debris Flow Deposits: East Greenland Slope 134 Andrew B. Stein, James P.M Syvitski 4 Ice Keel Scouring 136 Overview 136 Leonid Polyak Depth-Dependent Iceberg Plough Marks in the Barents Sea 138 Anders Solheim Deep Pleistocene Iceberg Plowmarks on the Yennak Plateau 140 Kathleen Crane, Peter R. Vogt, Eirik Sundvor Buried Ice-scours: 2D vs 3D-Seismic Geomorphology 142 David Long, Daniel Praeg Iceberg Turbate on Southeastern Baffin Island Shelf, Canada 144 Brian MacLean Strudel-Scour Craters on Shallow Arctic Prodeltas 146 Vlll Erk Reimnitz Ice-Wallow Relief in the Beaufort Sea 148 Erk Reimnitz Outcrop Morphology of Overconsolidated Mud in the Beaufort Sea 150 Erk Reimnitz Arctic Ice Gouging and Ice Keel Turbates 152 Peter W. Barnes, Erk Reimnitz Iceberg Gouges on the Antarctic Shelf 154 Peter W. Barnes 5 Other Features 157 Overview 157 Thomas A. Davies Gas-Related Sea Floor Depressions 158 Anders Solheim, Anders Elverhoi Water-Escape Sea Floor Depressions 160 James P. Syvitski Buried Fluvial Channels: 3D-Seismic Geomorphology 162 Daniel Praeg Buried Periglacial Drainage Channels on the New Jersey Outer Continental Shelf 164 Thomas A. Davies, James A. Austin, Jr. PART THREE GLACIMARINE ENVIRONMENTS/GEOMORPIDC PROVINCES 167 Glacimarine Environments/Geomorphic Provinces: Overview 169 Martyn S. Stoker 6 Fjords 173 Seismic and Side-Scan Sonar Investigations of Recent Sedimentation in an Ice-Proximal Glacimarine Setting, Kongsfjorden, North-West Spitsbergen 175 Robert J. Whittington, Carl Fredrik Forsberg, Julian A. Dowdeswell Seismic Signature of Glaciomarine Fjord Sediments from Central Norway 179 Dag Ottesen, Kare Rokoengen Typical Sections Along a Transect ofa Fjord in East Greenland 182 IX Frank Niessen, Robert J. Whittington Seismic Account of Ice-Proximal Sediments in a Small Glacial Inlet: Vikingebugt, Central East Greenland 186 Kris Vanneste, Gabriele Uenzelmann-Neben The Seismic Record of Glaciation in Nachvak Fiord, Northern Labrador 190 Trevor Bell, Heiner Josenhans Growth of a Grounding-Line Fan at Muir Glacier, Southeast Alaska 194 Keith C. Seramur, Ellen A. Cowan, Ross D. Powell, Paul R Carlson Glacial Marine Seismic Facies in a Southern Chilean Fjord 198 Jana L. DaSilva, John B. Anderson 7 Continental Shelves 203 A Surge Affected, Tidewater Glacier Environment 205 Anders Solheim Glacigenic Sedimentation and Late Neogene Climate Pattern 209 Allen Lowrie, Karl Hinz Glacigenic Features and Shelf Basin Stratigraphy of the Eastern Gulf of Maine 213 Tania S. Bacchus, Daniel F Belknap Glacial and Glaciomarine Sedimentation: Halibut Channel, Grand Banks of Newfoundland 217 K. Moran, G.B.J. Fader Morphology and Stratigraphy Related to the Nearshore Boundary of the Stamukhi Zone 222 Peter W. Barnes, Erk Reimnitz Larsen Shelf, Eastern Antarctic Peninsula Continental Margin 224 Benjamin J. Sloan, Lawrence A. Lawver Iceberg Plough Marks, Subglacial Bedforms and Grounding Zone Moraines in Prydz Bay, Antarctica 228 P.E. O'Brien, G. Leitchenkov, P. T. Harris Current and Glacial Erosion on the Shelf off Mac. Robertson Land, East Antarctica 232 P. T. Harris, P.E. 0 'Brien Till Sheets on the Ross Sea Continental Shelf, Antarctica 235 Stephanie Shipp, John B. Anderson Seismic Correlation Between CIROS-I and MSSTS-l Drill Holes, Ross Sea, Antarctica 238 Giuliano Brancolini, Franco Coren 8 Glacial Troughs 243 Bering Trough: a Product of the Bering Glacier, Gulf of Alaska 244 x