The Parascientific Pressure sensor located at the Delta Dynamics Laboratory platform caught the oceanic signal of the local 6.3 earthquake of September 9, 2011 (12:41 PDT). The pressure sensor is located on a bottom mounted platform and samples at a rate of ~700ms. The back-ground trend is the rising tide, on which is superimposed the surface pressure signature of tsunami like waves “sloshing” about in the Strait of Georgia. The signal also shows up in other pressure sensors at this and our other SoG locations, but because of the fast sample rate, this sensor shows enhanced variability.
See CBC article
At 05:46 UTC the 9.0 Earthquake started off the east coast of northern Japan. By 14:40 UTC (06:40 PST) the first waves of the Tsunami were detected by the bottom pressure recorders of the NEPTUNE regional network off the west coast of Vancouver Island.
By 16:30UTC, the water level in Saanich Inlet started to drop (shown here), as the wave crest entered Juan de Fuca Strait. A model developed by the Department of Fisheries and Oceans of a Tsunami entering Juan de Fuca predicts an arrival in Saanich a couple of hours after the leading depression first enters Juan de Fuca Strait.
The de-tided bottom pressure derived from the VENUS CTD located at a depth of 96m in Saanich Inlet reveals a complex oscillating series of seiches (surface sloshing like in a bathtub) lasting nearly 12 hours as the Tsunami dissipates among the channels of the Gulf Islands and the Strait of Georgia.
Note: The signals are still being analyzed for a complete and accurate interpretation.