The Arctic - A New Frontier The geological, environmental and engineering challenges for submarine telecommunication cables Ryan Wopschall 5 September 2013 Oceanology International China, Shanghai Fugro 2013
Presentation Overview The Arctic An Overview Geology, Environment and Ice The purpose and case for Arctic and other high latitude cables The Challenges Field investigation methods Submarine cable installation Maintenance and Repair The Growing Trends The submarine cable industry The Arctic
The Arctic An Overview The Arctic Ocean, Arctic States and Bathymetry
The Arctic An Overview The Arctic Ocean The Arctic Circle is approximately at 66 N above the Equator Smallest and shallowest of 5 major oceans Near-complete ice coverage about 9 months out of the year Sept. 81 Sept. 07 Sept. 91 Sept. 11 Annual multi-year ice coverage is shrinking
The Arctic An Overview Arctic Geology Coastal Zones Low lying Glacial-marine sediment Mixture of sand, pebbles and cobbles intermixed with silts and clays Arctic sedimentary geology with 500 m bathymetric contours (International Bathymetric Chart of the Arctic Ocean) Sediment Sources Glacial till Terrigenous sediment originating from erosion of rock on land Reworked marine sediments formed from ocean current activity
The Arctic An Overview Arctic Permafrost Coastal & Subsea Permafrost Soil at or below freezing for extended time, > 2yrs Shallow permafrost in coastal zones Majority of coastal areas in the Arctic range from having "discontinous permafrost (50-90%) to "continuous" permafrost (>90%) Soil condition is very stiff and can mimic bedrock and is hard to penetrate or displace The National Snow and Ice Data Center permafrost map for the Arctic region in Google Earth.
The Arctic An Overview Arctic Ice Young Ice 30 cm thick First Year Ice 1 to 2 m thick Multiyear Ice (Old Ice) 4 to 5 m thick Maximum Sea Ice Extent March 2012 Minimum Sea Ice Extent Sept. 2012
The Arctic An Overview Arctic Ice
The Arctic An Overview Submarine Cables and the Arctic (high latitude) Recent (select) submarine cable locations that have contributed to industry understanding. Greenland Alaska Planned tran- Arctic cables
The Arctic An Overview Planned Submarine Cables and the Arctic (high latitude) Europe Asia Links via Canadian / US Arctic Norway / Russian Arctic Purpose of Arctic cables Low latency, Europe/Asia Communication infrastructure for Arctic communities
The Challenges Marine Operations Field Investigations Methods Vessel-based geophysical and geotechnical surveys Airborne Lidar Specialized survey program designed around challenges Remote locations / limited resources and marine support Lack of quality hydrographic data / bathymetry, nautical charts Weather windows Ice windows / conditions Government regulations and restrictions Availability of suitable resources
The Challenges Marine Operations Field Investigations Vessel-based geophysical and geotechnical survey Multibeam Echo Sounder Side Scan Sonar Sub-bottom Profiler CPT and Coring Airborne Lidar Bathymetry (ALB) Operates in shallow water regions Extends survey over the beach Rapid response to new survey areas Complimentary with Sonar systems Shallow water Lidar vs. Multibeam
The Challenges Marine Operations ALB A system needs: Power A light source An accurate timing system An optical system A high-precision scanner A transceiver unit An attitude/motion input A mass storage device Software to define and extract all available data A credible processing workflow Provision of modern deliverables
The Challenges Marine Operations Field Investigations / Government Regulations
The Challenges Submarine Cable Installation Other than marine vessel operations, the main challenges are in the installation of a submarine cable Ice risk scour and frazil ice Ice Scour Caused by the winter buildup of shorefast ice and the melt-out and mobility of ice that scours the seafloor. Recent scours in the Arctic have occurred in water depths up to 60 meters and have penetrated the seafloor 1-1/2 to 2-1/2 meters. Ice scours tend to run in a common direction that is parallel to predominant ocean currents. Arctic Ice Scour bathymetry collected with Airborne Lidar in 20 m water depth
The Challenges Submarine Cable Installation Frazil Ice - Occurs in turbulent super cooled water 0.01 to 0.1 degrees below the freezing point. Occurs in rivers and oceans in cold regions where ice forms. Frazil ice may adhere to and propagate on the river/ocean bottom, rocks, or just about any underwater body that is also cooled to the same temperature. When frazil ice adheres to underwater structures, it is termed, anchor ice. Greg Wilt, GCI Anchor ice has been observed coating large rocks and boulders to the extent, they are floated off the bottom and transported considerable distances. Occurrences have been a nuisance to hydroelectric projects in Canada, Sweden, Russia and Iceland, to Arctic offshore gas explorations off Alaska s North Slope, and now to submarine cable. Greg Wilt, GCI
The Challenges Submarine Cable Installation Installation Methods Risks, Summarized Surface Lay Split Pipe Rock Dumping U-Anchoring Burial Plow Jetting Horizontal Drilling HDD Ice Scour Scour to depths of 60 m water depth Depth of scour from 1.5 to 2.5 m Frazil Ice Ice crystals create buoyancy to cable Observed to 33 m water depth
The Challenges Submarine Cable Installation Installation Methods HDD is the preferred method for best protection, but can be the most costly
The Challenges Submarine Cable Installation Installation Methods Other mitigation methods Ice Scour no proven best method other than burial Frazil Ice if no ice scour risk present, then the following could be used U-anchoring Plastic sheathing Heat tape or induced current through cable These methods will require Planning, site characterization and risk analysis Divers, ROV, good surface and sub-surface data Healthy budgets
The Growing Trends Submarine Cable Industry Diversification low latency Diversification cable congestion Arctic (high latitude) community infrastructure development Diversify / expand from satellite communication The Arctic Melting sea ice. Increases in shipping, fishing, natural resource exploration, hydrographic mapping, and tourism Will lead to Infrastructure development, i.e. communications, safety resources, coastal zone development
Thank You Contact: Ryan Wopschall rwopschall@fugro.com Fugro 2013