Seismicity of the Sumatra coast

Seismicity refers to the frequency, type and size of earthquakes experienced over a period of time.

The shallow seismicity is characteristically distributed across a wide area of plate movement.

Significant events which devastated coastal communities in the 20th and 21st centuries include: The seismicity of the Sumatra coast and the top six quakes ever recorded appear to be clustered in two time periods: a 12-year span between 1952 and 1964 and a 7-year span between the 2004 and 2011; however, this is understood as a statistical anomaly.

However, this does not fully demonstrate a relationship between events separated by longer periods and greater distances.

Much of the massive offshore seismicity have been highly tsunamigenic, claiming hundreds of thousands of lives along the coast and the entire rim of the Indian Ocean