Poster of the Indonesia Earthquake of of 06 April 2013 - Magnitude 7.0

Tectonic Summary

The April 6th, 2013 M 7.0 earthquake beneath Irian Jaya, Indonesia, occurred as a result of oblique-normal faulting, at a depth of approximately 70 km. At the location of this earthquake, the Pacific and Australia plates are converging at a rate of approximately 110 mm/yr in an east-northeast- west-southwest direction, resulting in the southward subduction of the Pacific plate beneath New Guinea at the New Guinea trench, north of the island. The depth and faulting mechanism of the April 6th earthquake indicate it likely ruptured a fault within the subducting Pacific lithosphere rather than on the shallower thrust interface between the two plates. This region of New Guinea is familiar with moderate-to-large earthquakes; several dozen events with magnitudes greater than 6 have occurred within 250 km of the April 6th earthquake over the past 40 years. Many of those events were shallow expressions of microplate interactions at the complicated boundary between the Pacific and Australia plates in this region. The 19 January 1981 M 6.7 earthquake, 140 km to the southeast, struck at a depth of 20 km and caused approximately 1300 fatalities. In July of 1976, a M 7.1 earthquake 210 km to the east-southeast struck just a few kilometers beneath the surface and resulted in around 6000 fatalities. In contrast, intermediate depth earthquakes like the April 6th 2013 event are much less hazardous, and do not generally cause significant damage or fatalities, though large intermediate-depth (70 - 300km) and deep-focus (depth > 300 km) earthquakes may be felt at great distances from their epicenters.

Earthquake Report


Thumbnail image of poster.


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.