NEPTUNE@Sea Blog Blog from 31-Aug-09

August 29 2009 we began a series of intensive dives to install instruments at our Ocean Drilling Program (ODP) 1027 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 observe changes in sub-surface temperatures and pressures caused by earthquakes, hydrothermal convection and regional plate strain. With live connections to the NEPTUNE Canada network, scientists will gain the ability to monitor stresses and fluid movements in real-time, as they occur.

On September 1, ROPOS attached connectors from our instrument platform to the temperature and pressure instruments on CORK 1026B. Eventually we hope to connect additional CORKs and CORK instruments to our network. More on CORKS.

Seismograph Network

The NEPTUNE Canada Seismograph Network will help seismologists do real-time seismic monitoring and research on the ocean floor. Altogether, we plan to install four broadband seismometers, forming a large footprint spanning our ODP 889, Barkley Canyon, ODP 1027 and Endeavour locations. Three of these broadband seismometers will be installed and connected to our network during the second leg of this summer's installation cruise.

West Coast "Tsunami-meter"

Results of this study will aid in tsunami, storm surge, and earthquake modeling. Highly sensitive bottom pressure recorders (BPRs) with built-in temperature and conductivity sensors will be located at all NEPTUNE Canada node locations. At ODP 1027, the plan calls for a triangular arrangement of 3 bottom pressure recorders, each positioned 12.5km from our instrument platform. Such an arrangement lets scientists make very precise measurements of deep water tsunami wave height, speed and direction of movement.

The 12.5km cables are challenging to lay. When spooled on ROCLS (the ROPOS Remotely Operated Cable Laying System) drums, they weigh over 3.7 metric tons. ROCLS, with spool attached, is lowered to the seafloor using the ship's winch. Then, ROPOS flies to the seafloor, unfastens the cable end from the spool, attaches it to the instrument platform, picks up ROCLS and gradually spools the cable out over the designated path. At the same time, the ship must slowly follow ROPOS, always keeping a careful eye to separation, orientation, track and sea conditions.

ODP 1027 Instrument Platform
Connection ports on the ODP 1027 instrument platform. Seabird conductivity-temperature-pressure gauge can also be seen.	Hose and connectors that will enable live data to be gathered from CORK 1026B via the NEPTUNE Canada network.	An inside view of the ODP1027 instrument platform. The two CORK connectors plug into CORK 1026B, nearby. The connector stowed in the parking station will hook to a seismometer.

On the Deck
Crews of the R/V Thompson and ROPOS work together to move a fully loaded ROCLS (3.7 metric tons) into position for deployment by crane to the seafloor.	Canadian Scientific Submersible Facility general manager Keith Shepherd prepares the ROCLS cable-laying frame for lowering to the seafloor by winch.	R/V Thompson crew used the ship winch to move the ODP 1027 instrument platform into position on deck prior to deployment by ROPOS, 29 August 2009.

On the Seafloor
ROPOS plugs a connector into the CORK 1026B pressure instrument, 1 September 2009.	ODP 1027 instrument platform during installation.	ROPOS rigs the extension cable connecting the ODP 1027 node to the instrument platform 3.5km away.	The ODP 1026B CORK wellhead from above. Two instruments, for monitoring temperatures and pressures within the earth's crust, are connected to the NEPTUNE Canada network. The top of this wellhead was inhabited by an octopus.

Local Sealife
A kind of sea cucumber (Scotoplanes sp.) we found crawling near ODP 1027.	This octopus seemed unintimidated by ROPOS, even while we removed the dust cover to the temperature instrument port and plugged in the connector.	This kind of sea cucumber is called a "Sea Pig".	A sea pen (Umbellula sp.) found at the ODP 1027 site.
Detailed view of a sea pen (Umbellula sp.) found at the ODP 1027 site.