Skinner, Matthew Robert2024-08-152024-08-1520022002https://hdl.handle.net/1828/19714Diatomaceous sediments in piston cores retrieved from the Effingham Inlet inner and outer basins. represent a complex history of episodic bioturbated intervals, turbidites, debris flows, and deformation structures set against a background of varved sedimentation. The turbidites initiated as slope failures and were characterized by either an abrupt transition from slump/slide blocks to fluid flow, or by liquefaction and flow of slope sediments . A combination of varve counting and AMS 14C dating has allowed accurate dating of 24 turbidites over approximately 3,300 years of the inner basin record. Known earthquakes recorded by turbidites include the AD 1946 Vancouver Island earthquake and AD 1700 plate-boundary earthquake. Eleven turbidites over the past 2,000 years of the inner and outer basin record are contemporaneous. Comparison of the event history obtained here and a similar record from Saanich Inlet has yielded 8 contemporaneous slope failures over the past 1,500 years, despite a physical separation of 130km.102 pagesAvailable to the World Wide WebThesis