A triple junction is the point where three tectonic plates diverge. These points are often near the epicenter of major megathrust earthquakes. For example: the triple junction of the Juan de Fuca Plate, the Pacific Plate and the North American Plate is close to the epicenter of the 1700, moment magnitude 9.0, Cascadia Earthquake; the triple junction of the Nazca Plate, the Antarctic Plate and the South American Plate is close to the epicenter of the 1960, moment magnitude 9.5, Great Chilean Earthquake and the triple junction of the Burma Plate, the India Plate and the Australian Plate is close to the epicenter of the 2004, moment magnitude 9.0, Indian Ocean Earthquake. Research on this connection is ongoing. Categories: Geology stubs | Plate tectonics ... The epicenter or epicentre (ancient Greek: επίκεντρον) is the point on the Earths surface that is directly above or below the center of a localized explosive event or point of seismic energy release. ... A megathrust earthquake is an interplate earthquake where one tectonic plate slips beneath (subducts) another. ... Categories: Geology stubs | Plate tectonics ... The Pacific Plate is an oceanic tectonic plate beneath the Pacific Ocean. ... The North American plate is shown in brown on this map The North American Plate is a continental tectonic plate covering the continent of North America, extending eastward to the Mid-Atlantic Ridge and westward to the Cherskiy Range in East Siberia. ... The moment magnitude scale (a successor to the Richter Scale), was introduced in 1979 by Tom Hanks and Hiroo Kanamori and is used by seismologists to compare the energy released by earthquakes. ... The Cascadia Earthquake was a magnitude 8. ... The Nazca plate is shown in light blue on this map The Nazca Plate is an oceanic tectonic plate in the eastern Pacific Ocean basin off the west coast of South America. ... The Antarctic Plate is a continental tectonic plate covering the continent of Antarctica and extending outward under the surrounding oceans. ... The South American Plate is a continental tectonic plate covering the continent of South America and extending eastward to the Mid-Atlantic Ridge. ... The Great Chilean Earthquake of May 22, 1960 is the largest magnitude earthquake in recorded history. ... The Burma Plate is a small tectonic plate located in Southeast Asia, often considered a part of the larger Eurasian Plate. ... The India or Indian Plate is a minor tectonic plate. ... Categories: Plate tectonics | Geology stubs ... The 2004 Indian Ocean earthquake was an undersea earthquake that occurred at 00:58:53 UTC (07:58:53 local time) on December 26, 2004. ...