2004 December 26, Sumatera-Andaman Islands, Mw 9.0
0058 UTC, 95.9°E, 3.3°N, rupture initiated at a depth of about 30 km [NEIC]
(Sunday, December 26 07:58 am, local time at the epicentre)
The epicentre of this earthquake was under the Indian Ocean, a little under 100 kilometres southwest of the northern Sumatera coast in Indonesia. The earthquake then took over five minutes to rupture northwards through the Nicobar Islands to the Andaman Islands. This enormous fault rupture was over 1100 kilometres long, and extended from the surface to great depth. The displacement across the fault would have varied from place to place, but usually exceeding ten to twenty metres. It is this vertical offset of the sea-floor that generated the tsunami. Many aftershocks occurred, up to magnitude 7.3, and aftershocks exceeding magnitude 6.0 continue to occur. These have average displacements from less than one metre for magnitude 6.0, to a little over two metres for magnitude 7.0. Some of these may be shallow enough to rupture up to the seafloor and could produce a tsunami, but very much smaller than that produced by the main shock. The number of fatalities and injuries, and the extent of the damage, are extreme. These are described elsewhere. This was the largest earthquake in the world since the Mw 9.2 Prince William Sound earthquake in Alaska, 1964 March 27 (UTC). It was the fourth largest instrumentally recorded earthquake, and the largest on on this very active plate boundary.
Here is a link to an animation of how the tsunami wave propagated.
For information on how a tsunami works, follow this link to the “How Stuff Works” website.
2004 December 23, North of Macquarie Is, Mw 8.1
1459 UTC, 160.4°E, 50.2°S, Shallow depth [NEIC]
(Friday, December 24 01:59 am AEDT)
This earthquake occurred in the Tasman Sea about 500 km north of Macquarie Is, about 1300 km southeast of Hobart and 1500 km southwest of Wellington, New Zealand. It was the largest earthquake in the world for the year, until the Sumatera-Andaman Islands earthquake three days later on the opposite side of the Australian Plate. The event was felt in Tasmania and in southern New Zealand.
2004 November 18, Roseberry, Tas, ML 4.7
2331 UTC, 146.1°E, 41.8°S, Normal [MEL]
(Thursday, November 19 10:31 am AEDT)
This earthquake occurred about 50 east of Roseberry, about 160km north west of Hobart. This event was felt.
2004 October 12, Brisbane Area, Qld
2345 UTC (approx)
(Wednesday, October 13 09:45 am AEST)
Vibrations were felt throughout the Brisbane area this morning (as far north as Caloundra), many people believing the source to be an earthquake. Investigations have ruled out earthquake, the source more likely a sonic boom or similar event.
2004 October 11, Skipton, Vic, ML 2.8
1636 UTC, 143.6°E, 37.9°S, normal depth [MEL]
(Wednesday, October 12 02:36 am AEST)
This earthquake was about 30km southeast of Skipton, about 135km west of Melbourne.
2004 September 21, Binalong, NSW, ML 2.7
1153 UTC, 148.6°E, 34.7°S, shallow depth [MEL]
(Tuesday, September 21 09:53 pm AEST)
This shallow earthquake was near Binalong, about 24 km west of Bowning, 36 km NW of Yass, and 87 km NW of Canberra. No reports of it being felt have been received.
2004 June 26, Frogmore, NSW, ML 2.6
0024 UTC, 148.7°E, 34.3°S, 3 km deep [MEL]
(Saturday, June 26 10:24 am AEST)
This earthquake occurred west of Frogmore, about 20 km north of Boorowa and 123 km north of Canberra.
2004 June 19, Barrington Tops, NSW, ML 2.7
0805 UTC, 151.5°E, 31.8°S, shallow depth [MEL]
(Saturday, June 19 06:05 pm AEST)
This earthquake was just north of the Barrington Tops, northeast of Scone and 135 km north of Newcastle.
2004 June 4, Glenthompson, Vic, ML 2.6
0432 UTC, 142.6°E, 37.6°S, 9 km deep [MEL]
(Friday, June 4 02:32 pm AEST)
This earthquake occurred near Glenthompson, about 26 km east of Dunkeld, south of the Grampians in western Victoria.
2004 May 15, Forster, NSW, ML 3.2
2138 UTC, 152.5°E, 32.4°S, normal depth [MEL]
(Sunday, May 16 07:38 am AEST)
This earthquake was near the coast about 25 km south of Forster, and about 100 km northeast of Newcastle. It was reported felt southwest of Tarree.
2004 May 14, Mt Field West, Tas, ML 2.5
1244 UTC, 146.6°E, 42.6°S, normal depth [MEL]
(Friday, May 14 10:44 pm AEST)
This earthquake occurred about 45 km northwest of New Norfolk, and 70 km northwest of Hobart.
2004 April 12, Lake Eildon, Vic, ML 2.7
0214 UTC, 146.0°E, 37.3°S, 10 km deep [MEL]
(Monday, April 12 12:14 pm AEST)
This earthquake occurred about 8 km northeast of Mt. Torbreck, 10 km west of Jamieson and 102 km northeast of Melbourne. An earthquake of this size may be felt to a distance of about 10 km, but since this event was at a depth of about 10 km it is unlikely that it would have been felt.
2004 March 11, Branxton, NSW, ML 3.2
2218 UTC, 151.3°E, 32.6°S, 10 km deep [MEL]
(Friday, March 12 07:18 am AEDT)
This earthquake occurred about 9 km northwest of Branxton and 53 km northwest of Newcastle. An earthquake of this size may be felt up to 30 km away.
2004 February 28, Wagga Wagga, NSW, ML 3.9
1132 UTC, 147.7°E, 35.1°S, 13 km deep [MEL]
(Saturday, February 28 10:32 pm AEDT)
This earthquake occurred about 25 km southeast of Junee and 140 km west of Canberra. An earthquake of this size may be felt up to 80 km away.