M 7.1 - 29 km SSW of Nabire, Indonesia

Tectonic Summary

The November 26, 2004, M 7.1 earthquake near Papua, Indonesia, occurred as the result of shallow, oblique slip on or near the transform faulting plate boundary between the Australia and Sunda plates. Focal mechanism solutions indicate that rupture occurred on either a near-vertical, right-lateral east-west-oriented fault or on a left-lateral, moderately dipping north-striking fault. The earthquake lies near the east-northeast trending boundary between the Birds Head and the Maoke microplates, which accommodates approximately 80 mm/yr of left-lateral motion. Surrounding Irian Jaya (the western half of New Guinea), four major tectonic plates (the Australia, Sunda, Philippine Sea, and Caroline plates) sandwich half a dozen proposed microplates. The interactions among these microplates produce all possible styles of faulting. In February 2003, three large earthquakes (M 7.0, M 7.3, and M 6.9) occurred over 3 days in the epicentral area of the November 26th event. There were at least 37 fatalities and more than 600 injured as a result of that sequence.

Hayes et al. (2016) Tectonic summaries of magnitude 7 and greater earthquakes from 2000 to 2015, USGS Open-File Report 2016-1192. (5.2 MB PDF)