Region: Located in the centre of Cascadia Basin—a heavily sedimented abyssal plain region, which extends from the base of the continental margin to the mid-ocean ridge.
On the evening of May 19th, the scientific ocean drilling vessel JOIDES Resolution (JR) set out from Victoria B.C. for nine days in the deep Pacific waters off shore Vancouver Island, with excited staff from Ocean Networks Canada and the University of Victoria on board.
For over three decades, a fundemental goal for scientific ocean drilling has been to understand the role of the presence and flow of water in marine geologic formations on processes like heat loss from the earth, chemical exchange between the Earth’s oceans and crust, support of subseafloor microbiological ecosystems, and the creation of methane-hydrates and ore deposits. The quality of direct observations is commonly compromised by a simple problem: boreholes create hydrologic “short circuits” that allow open exchange of water between subseafloor formations and the ocean. The resulting perturbations severely limit the utility of temperature and pressure observations and of water samples taken during or shortly after drilling operations.
A magnitude 7.4 earthquake struck the state of Oaxaca, Mexico at 12:02 local time, 20 March 2012. This region is above a tectonic plate boundary where the Cocos Plate is being subducted below the North American Plate at a rate of 6.4 cm/yr. Moderate to very strong shaking was experienced throughout an area within 100km of the epicenter.
24 minutes later, the seafloor pressure sensor on CORK 1026B at our Cascadia Basin (formerly ODP 1027) location sensed the pressure waves as they propagated through the earth. This trace shows these observations:
The W.M. Keck Foundation has awarded $1 Million to Woods Hole Oceanographic Institution (WHOI) for a new geodesy observatory to be connected to Ocean Networks Canada and the Ocean Observatories Initiative Regional Scale Nodes (OOI RSN). This interdisciplinary project, led by Dr.Jeff McGuire and John Collins of WHOI, will allow scientists to monitor three Cascadia subduction zone segments off the coasts of Vancouver Island, Washington and Oregon. Along this subduction zone, the Juan de Fuca plate...
From July 4 - 25, 2011, Ocean Networks Canada navigated an impressive installation and maintenance expedition in the northeast Pacific Ocean. Diving down to the seafloor to investigate our 800-km cabled network observatory along the northern Juan de Fuca plate, we tended to our technically-advanced instruments and witnessed some of the amazing marine life dwelling off the coast of Vancouver Island, British Columbia.
The JOIDES Resolution research drillship, a key vessel in the Integrated Ocean Drilling Program (IODP), was docked in Victoria this summer for three months of refit work before heading out on two cruises in July and September.
New Boreholes
The Juan de Fuca Plate is a hot-spot of scientific ocean drilling. Since ODP expedition 139 in 1991, numerous boreholes have been drilled in the...
Our Spring 2010 installation & maintenance cruise sailed May 8-24 aboard the CCGS John P Tully. It was a very busy time for 4 Ocean Networks Canada staffers, 2 contractors, 1 student and 1 Canadian Navy officer who joined 8 ROPOS crew members and the 21-member CCGS Tully roster. In the space of 16 days we completed 21 ROPOS dives at 5 locations, including one dive to the Fraser Delta site in the Strait of Georgia.
When a devastating magnitude 8.0 earthquake occurred roughly 200 km south of the Samoan Islands at 17:48:11 UTC on Tuesday September 29, 2009, it generated a trans-oceanic tsunami that spread at jet-like speeds throughout the Pacific Ocean.
At 04:57:33 UTC on 30 September, roughly 11 hours after the earthquake, five of our newly deployed Bottom Pressure Recorders (BPRs) and one...
On 29 August 2009 we began a series of intensive dives to install instruments at our Ocean Drilling Program (ODP) 1027 (Cascadia Basin) location. This site, in the centre of the Juan de Fuca Plate, is critically important for several NEPTUNE Canada research projects, including Ocean Crustal Hydrogeology , Seismograph Network and West Coast "Tsunami-meter" .
Ocean Crustal Hydrogeology
Ten boreholes were drilled across the Juan de Fuca Plate between 1991 and 2003 by the Ocean and Integrated Ocean Drilling Programs (ODP/IODP) expressly for the installation of "CORK" (Circulation Obviation Retrofit Kit) hydrologic observatories. These CORKs allow geoscientists to...
