Poster of the Off the West Coast of Northern Sumatra Earthquake of 10 January 2012 - Magnitude 7.3

Tectonic Summary

The January 10, 2012 earthquake off the west coast of northern Sumatra, Indonesia, occurred as a result of strike-slip faulting within the oceanic lithosphere of the Indo-Australia plate, approximately 100 km to the southwest of the major subduction zone that defines the plate boundary between the Indo-Australia and Sunda plates offshore Sumatra. At the location of this earthquake, the Indo-Australia plate moves north-northeast with respect to the Sunda plate at a velocity of approximately 52 mm/yr.

While they are rare, large strike-slip earthquakes are not unprecedented in this region of the Indo-Australian plate. Since the massive M 9.1 earthquake that ruptured a 1300 km long segment of the Sumatran megathrust plate boundary in December of 2004, two Mw 6.2 strike-slip events have occurred within 50 km of the January 10 2012 event, on April 19 2006, and October 4 2007. These events seem to align with fabric of the sea floor in the diffuse boundary zone between the Indian and Australian plates.

Earthquake Report

Downloads

Thumbnail image of poster.

Settings

The posters may be downloaded for viewing or for printing on a color plotter. Adobe PDF (.pdf) format files are provided. Adobe Acrobat 6.0 or higher is required for viewing the PDF file on a computer monitor and for printing the PDF map graphic.

Attention MAC users: If you have problems viewing the pdf files, please download the pdf file and view it in the lastest verion of Adobe Acrobat.