Puget Sound faults about 1100 years ago (AD 900—930) an earthquake of magnitude 7+ uplifted Restoration Point and Alki Point, dropped West Point (the three white triangles in the Seattle Basin on the map), caused rockslides in the Olympics, landslides into Lake Washington, and a tsunami on Puget Sound. It extends as far east as (and probably terminates at) the Rattlesnake Mountain Fault Zone (RMFZ; the southern extension of the SWIF) near Fall City. This seems geologically reasonable, as both the SWIF and RMFZ appear to be the contact between Tertiary Crescent Formation basement of Puget Sound on the west and the older
South Puget Sound shelter whale calves. Southern resident killer whales (orcas) have been reported as far south as Eld Inlet. Smaller species include Dall's porpoise (Phocoenoides Dalli), harbor seals (Phoca Vitulina) and the Pacific harbor porpoise (Phocoena phocoena). A single sea otter was sighted in the South Sound in 2012. South Puget Sound South Puget Sound is the southern reaches of Puget Sound in Southwest Washington, in the United States' Pacific Northwest. It is one of five major basins encompassing the entire Sound, and the shallowest basin, with a mean depth of . Exact definitions of the region vary: the state's Department of