This floating dock washed ashore near Newport. Ore. on June 5.
The dock that washed ashore in Oregon is 66 feet long and covered with an estimated ton of marine life.
An engraving on the dock allowed officials to trace it back to Japan.
Wakame, a known invasive seaweed, clinging to the "tsunami dock" on an Oregon beach.
Among the species on the Japanese dock are these exotic mussels (Mytilus edulis or M. galloprovicialis) and unknown barnacles.
A view of the mussels and barnacles that cling to the Japanese dock.
An exotic pink Japanese acorn barnacle on the dock that washed ashore in Oregon.
In this photo released by NOAA, a boat lost in the Japanese tsunami of 2011 sits onshore on a remote Canadian island. The boat was discovered Aug. 9, 2012.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.