Seismicity of the Sanriku coast
The seismicity of the Sanriku coast identifies and describes the seismic activity of an area of Japan. Seismicity refers to the frequency, type and size of earthquakes experienced over a period of time. The Sanriku Coast is a descriptive term referring to the coastal areas of the former provinces of Rikuō in Aomori, Rikuchū in Aomori, and Rikuzen in Miyagi.
Historical tsunamis in the Sanriku area and selection of areas affected by the 2011 Tōhoku tsunami
A ria is a coastal inlet formed by the partial submergence of an unglaciated river valley. It is a drowned river valley that remains open to the sea.
Port Jackson, also referred to as Sydney Harbour, is a ria, or drowned river valley. The deeply indented shape of the ria reflects the dendritic pattern of drainage that existed before the rise in sea level that flooded the valley.
A satellite view of Galicia
Ria of San Vicente de la Barquera in Cantabria, Spain
Ria of Rijeka Dubrovačka in Dubrovnik, Croatia