Courtesy of NEPTUNE Canada
1st Stop: ODP 889 Node area survey
Ocean Drilling Program (ODP) 889 is located on the continental slope West of Vancouver Island
Purpose: Run a West to East 40km route survey of the continental slope topography via ROPOS Canada ROV sector scanning sonar. It is important to survey this underwater topography to determine the hardness of the sediment where the fiber-optic cable will be buried. The main cable will be buried in 1meter of sediment from shore to a water depth of 1500 meters, so that local fishermen don't disturb the cable or vice-versa. When the main cable reaches a water depth greater than 1500 meters it will no longer need to be buried. Another important reason for the survey is to ensure that no obstacles (boulder outcrops etc.) disrupt the path of the skids plowing and burying the back bone main cable of the NEPTUNE 1st stage. Budgeting cable costs can be accurately estimated by the topography of the cable path. Rougher terrain requires thicker gauge cable that is more expensive than smaller gauge cable. Once the main cable is laid and buried it will be ready to host a node connected to a y-shaped spur in the cable at site ODP 889, where another cable can branch off the node running South East with instruments listed in the figure above. This node has plug in expansion capability. Particularly interesting are the buried methane hydrates along the Bulls Eye vent area. Some of the scientific instruments will be monitoring the changes of these gas hydrates qualities such as venting and their effects on the biology of the area. (NEPTUNE Canada website & conversation with Project Scientist Brian Bornhold August 2, 2007).