Strudel Scour Formation Off Arctic River Deltas

Leidersdorf, Craig B.; Hearon, Gregory E.; Vaudrey, Kennon D.; Swank, Greg

doi:10.1142/9789812709554_0445

“…The change in strudel scour regime after start-up of operations has been investigated by Leidersdorf et al (2006). The change in strudel scour regime after start-up of operations has been investigated by Leidersdorf et al (2006).…”

Section: Strudel Scour and Hydrodynamic Scourmentioning

confidence: 99%

Arctic Offshore Pipeline Design and Installation Challenges

Paulin

¹

2014

View full text Add to dashboard Cite

With the oil industry's continued quest for oil and gas in frontier offshore locations, several developments have taken place in regions characterized by seasonal ice cover including the US Beaufort, North Caspian, and Sakhalin Island. In these projects, pipeline transportation systems have been used, which are a cost effective, safe and reliable mode of hydrocarbon transport to shore. Ice gouging is one of the key design issues that affect engineering considerations with respect to strain based design, target burial depth requirements, cost, and safety.It is generally accepted that offshore pipelines in ice environments will need to be trenched and backfilled for protection. Burial depths can be greater than those that might normally be required for pipelines in temperate climates. Burial depth requirements will be a function of the design ice gouge depth (to prevent interaction between the ice and pipe) and an acceptable level of subgouge deformation beneath a gouging ice keel (which potentially strains the pipeline). There still exists uncertainty on the magnitude and extent of subgouge soil deformations due to ice gouging and the importance of sediment transport mechanisms for biasing gouge statistics.Other challenges that must be considered include strudel and hydrodrnamic scour, thaw settlement and frost heave, and upheaval buckling. These considerations may also influence burial depth requirements.

show abstract

“…The change in strudel scour regime after start-up of operations has been investigated by Leidersdorf et al (2006). Annual monitoring of the strudel scours formed in the vicinity of the Northstar pipelines indicate that pipeline operations may locally increase the probability of scour formation.…”

Section: Strudel Scour and Hydrodynamic Scourmentioning

confidence: 99%

“…Annual monitoring of the strudel scours formed in the vicinity of the Northstar pipelines indicate that pipeline operations may locally increase the probability of scour formation. The cause of the increase in the frequency of scour formation over the pipelines may be the local thinning of the ice sheet above a buried warm pipeline in shallow water (Leidersdorf et al, 2006).…”

Section: Strudel Scour and Hydrodynamic Scourmentioning

confidence: 99%

Arctic Offshore Pipeline Design and Installation Challenges

Paulin

¹

2013

All Days

0

View full text Add to dashboard Cite

With the oil industry's continued quest for oil and gas in frontier offshore locations, several developments have taken place in regions characterized by seasonal ice cover including the US Beaufort, North Caspian, and Sakhalin Island. In these projects, pipeline transportation systems have been used, which are a cost effective, safe and reliable mode of hydrocarbon transport to shore. Ice gouging is one of the key design issues that affect engineering considerations with respect to strain based design, target burial depth requirements, cost, and safety.It is generally accepted that offshore pipelines in ice environments will need to be trenched and backfilled for protection. Burial depths can be greater than those that might normally be required for pipelines in temperate climates. Burial depth requirements will be a function of the design ice gouge depth (to prevent interaction between the ice and pipe) and an acceptable level of subgouge deformation beneath a gouging ice keel (which potentially strains the pipeline). There still exists uncertainty on the magnitude and extent of subgouge soil deformations due to ice gouging and the importance of sediment transport mechanisms for biasing gouge statistics.Other challenges that must be considered include strudel and hydrodrnamic scour, thaw settlement and frost heave, and upheaval buckling. These considerations may also influence burial depth requirements.

show abstract

“…Alternatively, dynamic sea-ice interaction with the shore may be destructive or constructive, depending on the situation, as ice-driven onshore can erode the backshore and damage infrastructure (Taylor, 1978;Kovacs and Sodhi, 1981), but may also nourish the shore zone through landward transport of nearshore sediments . In the Arctic during the spring thaw, river discharge onto a frozen ocean may drain through cracks and sinkholes to create distinctive strudel scour depressions on the seabed that represent a hazard to pipelines (Reimnitz and Bruder, 1972;Leidersdorf et al, 2006). Many other distinctive nearshore and beachface features attributable to shore ice on cold coasts are described later in the chapter (see also Forbes and Taylor, 1994;Byrne and Dionne, 2002).…”

Section: Ice As the Distinguishing Feature Of Polar And Subpolar Coastsmentioning

confidence: 99%

“…As overflow water begins to drain below the buoyant floating ice through tidal cracks or other orifices, the bottomfast ice remains bonded to the seabed. Strudel scour is now recognized as an active process with important implications for seabed infrastructure in the Prudhoe Bay field (Leidersdorf et al, 2006;Hearon et al, 2009) and the process has recently been confirmed off the Mackenzie Delta (Solomon et al, 2008). These are most abundant just beyond the transition from bot tomfast to floating ice in depths of 1.4-5 m (Reimnitz et al, 1974).…”

Section: Polar Deltasmentioning

confidence: 99%