The “three-layer cake” of Cascadia tsunami geology is very well preserved in geologic layers beneath salt marsh deposits along the banks of the Niawiakum River east of Willapa Bay in southwest Washington state. The bank of the river was cleaned by shovel work to produce a vertical face. Water was then splashed on that face to remove streaks of clay and fine particles resulting from the shovel action. This poster-size photograph is 28 inches wide by 21 inches tall. It is nearly life size. The red and white bars on the shovel handle are 10 centimeters (4 inches) long. By printing this photo on a large-format printer at full size, you can produce a poster for a classroom wall or bulletin board.