Submarine Mass Movements and Their Consequences: 5th International Symposium

ISBN-13: 9789400721616 / Angielski / Twarda / 2011 / 769 str.

Yasuhiro Yamada; Kiichiro Kawamura; Ken Ikehara

Opis

Submarine mass movements represent major offshore geohazards due to their destructive and tsunami-generation potential. This potential poses a threat to human life as well as to coastal, nearshore and offshore engineering structures. Recent examples of catastrophic submarine landslide events that affected human populations (including tsunamis) are numerous; e.g., Nice airport in 1979, Papua-New Guinea in 1998, Stromboli in 2002, Finneidfjord in 1996, and the 2006 and 2009 failures in the submarine cable network around Taiwan. The Great East Japan Earthquake in March 2011 also generated submarine landslides that may have amplified effects of the devastating tsunami. Given that 30% of the World's population live within 60 km of the coast, the hazard posed by submarine landslides is expected to grow as global sea level rises. This elevated awareness of the need for better understanding of submarine landslides is coupled with great advances insubmarine mapping, sampling and monitoring technologies. Laboratory analogue and numerical modeling capabilities have also developed significantly of late. Multibeam sonar, 3D seismic reflection, and remote and autonomous underwater vehicle technologies provide hitherto unparalleled imagery of the geology beneath the oceans, permitting investigation of submarine landslide deposits in great detail. Increased and new access to drilling, coring, in situ measurements and monitoring devices allows for ground-thruth ofgeophysical data and provides access to samples for geotechnical laboratory experiments andinformation on in situstrength and effective stress conditions of underwater slopes susceptible to fail. Great advances in numerical simulation techniques of submarine landslide kinematics and tsunami propagation, particularly since the 2004 Sumatra tsunami, have also lead to increased understanding and predictability of submarine landslide consequences.

This volume consists of the latest scientific research by international experts in geological, geophysical, engineering and environmental aspects of submarine mass failure, focused on understanding the full spectrum of challenges presented by submarine mass movements and their consequences.

Spis treści

1  Submarine Mass Movements and Their Consequences

Part I Physical Properties of Sediments and Slope Stability Assessment

2  Risk Assessment for Earthquake-Induced Submarine Slides

3  Shallow Landslides and Their Dynamics in Coastal and Deepwater Environments, Norway

4  Physical Properties and Age of Continental Slope Sediments Dredged from the Eastern Australian Continental Margin – Implications for Timing of Slope Failure

5  Submarine Landslides on the Upper Southeast Australian Passive Continental Margin – Preliminary Findings

6  Development and Potential Triggering Mechanisms for a Large Holocene Landslide in the Lower

St. Lawrence Estuary

7  Spatially Fixed Initial Break Point and Fault-Rock Development in a Landslide Area

8  Pore Water Geochemistry as a Tool for Identifying and Dating Recent Mass-Transport Deposits

9  An In-Situ Free-Fall Piezocone Penetrometer for Characterizing Soft and Sensitive Clays at Finneidfjord (Northern Norway)

10  Static and Cyclic Shear Strength of Cohesive and Non-cohesive Sediments

11  Upstream Migration of Knickpoints: Geotechnical Considerations

Part II Seafloor Geomorphology for Trigger Mechanisms and Landslide Dynamics

12  A Reevaluation of the Munson-Nygren-Retriever Submarine Landslide Complex, Georges Bank Lower Slope, Western North Atlantic

13  Submarine Landslides in Arctic Sedimentation: Canada Basin

14  Extensive Erosion of the Deep Seafloor – Implications for the Behavior of Flows Resulting from Continental Slope Instability

15  Investigations of Slides at the Upper Continental Slope Off Vesterålen, North Norway

16  Dakar Slide Offshore Senegal, NW-Africa: Interaction of Stacked Giant Mass Wasting Events and Canyon Evolution

17  Large-Scale Mass Wasting on the Northwest African Continental Margin: Some General Implications for Mass Wasting on Passive Continental Margins

18  Deep-Seated Bedrock Landslides and Submarine Canyon Evolution in an Active Tectonic Margin: Cook Strait, New Zealand

19  Polyphase Emplacement of a 30 km3 Blocky Debris Avalanche and Its Role in Slope-Gully Development

20  Slope Failure and Canyon Development Along the Northern South China Sea Margin

21  Distinguishing Sediment Bedforms from Sediment Deformation in Prodeltas of the Mediterranean Sea

22  Hydroacoustic Analysis of Mass Wasting Deposits in Lake Ohrid (FYR Macedonia/Albania)

23  New Evidence of Holocene Mass Wasting Events in Recent Volcanic Lakes from the French Massif Central (Lakes Pavin, Montcineyre and Chauvet) and Implications for Natural Hazards

Part III Role of Fluid Flow in Slope Instability

24  A Review of Overpressure, Flow Focusing, and Slope Failure

25  How Do ~2° Slopes Fail in Areas of Slow Sedimentation? A Sensitivity Study on the Influence of Accumulation Rate and Permeability on Submarine Slope Stability

26  The BGR Slide Off Costa Rica: Preconditioning Factors, Trigger, and Slide Dynamics

27  Detailed Observation of Topography and Geologic Architecture of a Submarine Landslide Scar in a Toe of an Accretionary Prism

28  Possible Ground Instability Factor Implied by Slumping and Dewatering Structures in High-Methane-Flux Continental Slope

29  Identification of Weak Layers and Their Role for the Stability of Slopes at Finneidfjord, Northern Norway

30 Mass Movements in a Transform Margin Setting: The Example of the Eastern Demerara Rise

Part IV Mechanics of Mass-Wasting in Subduction Margins

31  Slope Failures in Analogue Models of Accretionary Wedges

32  Systematic Development of Submarine Slope Failures at Subduction Margins: Fossil Record of Accretion-Related Slope Failure in the Miocene Hota Accretionary Complex, Central Japan

33  Morphologic Expression of Accretionary Processes and Recent Submarine Landslides Along the Southwestern Pacific Margin of Colombia

34  Submarine Mass Wasting Off Southern Central Chile: Distribution and Possible Mechanisms of Slope Failure at an Active Continental Margin

35  An Overview of the Role of Long-Term Tectonics and Incoming Plate Structure on Segmentation of Submarine Mass Wasting Phenomena Along the Middle America Trench

Part V Post-Failure Dynamics

36  Dynamics of Submarine Liquefied Sediment Flows: Theory, Experiments and Analysis of Field Behavior

37  Undrained Sediment Loading Key to Long-Runout Submarine Mass Movements: Evidence from the Caribbean Volcanic Arc

38  Impact Drag Forces on Pipelines Caused by Submarine Glide Blocks or Out-Runner Blocks

39  A Surging Behaviour of Glacigenic Debris Flows

40  Failure Processes and Gravity-Flow Transformation Revealed by High-Resolution AUV Swath Bathymetry on the Nice Continental Slope (Ligurian Sea)

41  Submarine Landslides, Gulf of Mexico Continental Slope: Insights into Transport Processes from Fabrics and Geotechnical Data

Part VI Landslide Generated Tsunamis

42  Tsunamis Generated by Submarine Landslides

43  Micro-bathymetric Evidence for the Effect of Submarine Mass Movement on Tsunami Generation During the 2009 Suruga Bay Earthquake, Japan

44  Re-evaluation of the 1771 Meiwa Tsunami Source Model, Southern Ryukyu Islands, Japan

45  The 1978 Quick Clay Landslide at Rissa, Mid Norway: Subaqueous Morphology and Tsunami Simulations

46  Geowave Validation with Case Studies: Accurate Geology Reproduces Observations

47  Tsunami Hazards for Nuclear Power Plants: Mass Failures, Uncertainty, and Warning

Part VII Witnessing and Quasi-Witnessing of Slope Failures

48  Submarine Slope Response to Earthquake Shaking Within Western Sagami Bay, Central Japan

49  Discovery of Submarine Landslide Evidence Due to the 2009 Suruga Bay Earthquake

50  Settling of Earthquake-Induced Turbidity on the Accretionary Prism Slope of the Central Nankai Subduction Zone

51  Study of Recent Small-Scale Landslides in Geologically Active Marine Areas Through Repeated Multibeam Surveys: Examples from the Southern Italy 

Part VIII Architecture of Mass Transport Deposits/Complexes

52  Sedimentary Mélanges and Fossil Mass-Transport Complexes: A Key for Better Understanding Submarine Mass Movements?

53  The Specchio Unit (Northern Apennines, Italy): An Ancient Mass Transport Complex Originated from Near-Coastal Areas in an Intra-Slope Setting

54  Internal Stress Fields of a Large-Scale Submarine Debris Flow

55  Distribution of Submarine Mass Movement Deposits: An Exhumed Basin Perspective

56  Seismic-Scale Rafted and Remnant Blocks over Salt Ridges in the Espírito Santo Basin, Brazil

57  Permian and Triassic Submarine Landslide Deposits in a Jurassic Accretionary Complex in Central Japan

58  Systematic Spatial Variations in the Fabric and Physical Properties of Mass-Transport Deposits in the Ursa Region, Northern Gulf of Mexico

59  Records of Submarine Landslides in Subduction Input Recovered by IODP Expedition 322, Nankai Trough, Japan

60  Scientific Drilling of Mass-Transport Deposits in the Nankai Accretionary Wedge: First Results from IODP Expedition 333

61  Rock-Magnetostratigraphy of Hawaiian Archipelagic Sediments: Timing of Giant Submarine Landslides of the Hawaiian Ridge

62  Gravity Flow Deposits in the Deep Rockall Trough, Northeast Atlantic

Part IX Relevance of Natural Climate Change in Triggering Slope Failures

63  Submarine Mass Wasting in Isfjorden, Spitsbergen

64  Comparison of Quaternary Glaciogenic Debris Flows with Blocky Mass-Transport Deposits in Orphan Basin, Offshore Eastern Canada

65  Recent Submarine Landslides on the Continental Slope of Storfjorden and Kveithola Trough-Mouth Fans (North West Barents Sea)

66  One Million Years of Climatic Generated Landslide Events on the Northwestern Barents Sea Continental Margin

Author Index

Subject Index