Ice Scour Risk and Protection on the Grand Banks
Keywords:COASTAL ENGINEERING, 8751, CASE STUDY, OCEAN and NAVAL, ICE SCOUR, EDC, GRAND BANKS, TERRA NOVA,
AbstractHydrocarbons were first discovered offshore Newfoundland in the late 1970s and full-scale production of these discoveries began in earnest in 1997 with the Hibernia oil field. The estimated total recoverable oil reserves on the Grand Banks are currently around 2100 MMbbls (million barrels), with additional potential reserves of more than 3000 MMbbls. In addition, there is estimated to be as much as 6800 BCF (billion cubic feet) in natural gas reserves with an additional 4000 BCF located on the Labrador shelf . Most current and planned oil field developments on the Grand Banks consist of subsea completions involving wellheads, manifolds, flow lines and risers. This method of subsea production is becoming increasingly popular in harsh environments (such as the Norwegian and Barents Sea) as well as for the economic development of marginal fields. The prevalence of icebergs off the coast of Newfoundland and Labrador represents a significant risk of damage to these subsea completions and this risk must be mitigated to an acceptable level for the technologies to be safely utilized. The most successful mitigation has been the implementation of excavated drill centres, EDCs (formerly known as glory holes). The following paper will provide a brief description of the environmental threats present in ice environments, a description of past projects, and the challenges inherent with creating the EDCs on the Grand Banks.
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