Earthquakes in Western Australia

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Earthquakes have occurred in Western Australia (WA) on a regular basis throughout its geological history.

In 1849, the first earthquake following European settlement in WA was recorded. "On Saturday last, about a quarter past four o'clock a.m., several inhabitants of Perth were awoke by what they conceived to be a slight shock of an earthquake."[1][2][3]

The largest earthquake affecting Western Australia in modern times was an offshore earthquake in 2019, occurring 202 km west of Broome at a magnitude of 6.6 causing minor damage in the town itself. The strongest earthquake with its epicentre on land is the magnitude 6.5 Meckering earthquake of 1968, which caused injuries to at least 17 people and extensive property damage; it was the best-known earthquake in Western Australia the late twentieth century. The previous largest earthquake documented occurred in 1941, at Meeberrie, in the Murchison region. Like many earthquakes it remained little known, due to its lack of impact on urban areas. Initially reported at magnitude 7.2 – 7.3 it was eventually revised down to 6.3 in by Geoscience Australia in 2016. The Meckering quake was also revised down from 6.9 to 6.5 in the same year but in the process overtook the Meeberrie quake in strength.[4]

Recording[edit]

Prior to scientific equipment being utilised to record earthquakes, newspaper reports appear to be the main source of historical information.[5] Perth Observatory was the recording location from 1923 to 1959, when the Mundaring Geophysical Observatory was operated by the Bureau of Mineral Resources between March 1959 and April 2000.[6] Subsequent to the closing of the Mundaring observatory, recording locations are more dispersed throughout the state.[7]

Significant earthquakes[edit]

locations of significant earthquakes

Western Australia's largest recorded earthquake to date was at Meeberrie station, north of Mullewa, in April 1941. See the separate section below. The Cadoux earthquake of 1979 with magnitude 6.1 caused surface rupturing, about 15 km (9.3 mi) long.[8]

Earthquakes at Meckering, Calingiri (several during 1970 and 1971) and Cadoux led to the identification of a zone of seismicity known as the South West Seismic Zone.[9] This zone has now been significantly mapped and analysed and is the most active zone in Western Australia.[10]

Exmouth 1906[edit]

The earthquake which occurred in 1906 about 400 km (250 mi) NW of Exmouth occurred before world earthquake monitoring had really developed. With an estimated magnitude of 7.5, it is probably the largest earthquake known to have occurred in the Australian region.[11][12]

Kalgoorlie 1917[edit]

On 28 August 1917, tremor was reported near midnight in Kalgoorlie, which resulted in an underground rock fall, killing one miner and injuring several others.[9] Also in the 1990s further seismic activity required consideration of seismic activity.[13]

Meeberrie Station 1941[edit]

The largest earthquake to date in Western Australia was on 29 April 1941 at Meeberrie at 01.35.39 am (Lat −26.90 and Long 115.80) with a magnitude of 7.3. (Some sources give 7.2.)[14][15][16]

Yallingup 1946[edit]

On 20 April 1946 a magnitude 5.7 earthquake occurred near Yallingup at 9:13pm on 19 April 1946 (5:13 local time on 20 April), which was felt at Kirup. A tremor was reported at 5:30 am at Caves House Yallingup and at Busselton on 30 April, which is probably the same event, reported on the wrong date.[9]

Gabalong 1955[edit]

Gabalong, 30 August 1955, magnitude 5.8 Gabalong, a small community about 30 km (19 mi) east of Moora and 200 km (120 mi) NNE of Perth. The earthquake, at 9.52 pm local time, was felt at MM VI at Yericoin and Miling, and MM V in Moora. It was felt in Perth at intensities between MM II and MM IV, and at Dongara at MM II. It was preceded by a magnitude 5.3 earthquake at the same location at 2.09 pm on the same day. It was a SouthWest Seismic Zone earthquake, and because of the poor location capabilities at the time, may well be related to a series of earthquakes near Yericoin, which started with a magnitude 5.1 earthquake on 2 May 1949.[9]

Busselton 1959[edit]

A magnitude 5.0 earthquake occurred at 12:07 GMT on 3 October (8.07 pm local time) at 34.5 degrees south, 114.5 degrees east. It was felt at Busselton, Yallingup, Margaret River, Bunbury, Cape Naturaliste and Cape Leeuwin.[9]

Near Brookton 1963[edit]

18 January 1963 at Nourning Spring, approximately 20 km (12 mi) NE of Brookton and approximately 100 km (62 mi) ESE of Perth. It was felt at Intensity VII at Nourning Springs, VI at Brookton, and MM II at Perth. It occurred at 1:49 pm local time, and had a magnitude of 5.4, although it was given a magnitude of 4.9 originally. Many earthquake questionnaires were distributed for this event, and a good isoseismal map was prepared.[9]

Meckering 1968[edit]

On the 14th of October 1968 at 10:59am, an earthquake registering 6.9 on the Richter scale occurred 100 km (62 mi) east of Perth in Meckering, Western Australia.[3] Injuring 20 people, causing over 2 million dollars in damage and felt in towns 650 km (400 mi) away, it is Western Australia's most destructive earthquake to date.

The hypocentre occurred 7 km (4.3 mi) below the earth's surface in the Yandanooka/Cape Riche Lineamen region located east of Meckering. The fault trended on a 32 km (20 mi) north-south arc. Through strike-slip the eastern side of the arc shoved 2 m (6 ft 7 in) westward, 1.5 m (4 ft 11 in) upwards and 0.9 m (2 ft 11 in) in a southerly direction which left a distinct trench in its path. This intraplate earthquake is thought to be caused through east-west compressional force within the southwest seismic zone.

Lake Tobin 1970[edit]

24 March 1970, magnitude 6.7 near Lake Tobin in the Canning Basin, was the first in a location which had many more earthquakes over the following years. In all, there were three earthquakes of magnitude 6.0 or more (24/3/70, M 6.7, 16/7/71, M6.4 and 3/10/75, M 6.2), and 25 earthquakes of magnitude 5.0 or more, the last of which occurred on 13/2/1982.[9]

Calingiri 1970 & 1971[edit]

An earthquake struck the Wheatbelt town of Calingiri on 10 March 1970[19] with a magnitude of 5.9. No buildings were damaged despite the epicentre being 3 km (1.9 mi) from the town and the surface being uplifted as much as 30 cm (12 in).[20]

Cadoux 1979[edit]

On 2 June 1979 the second-most damaging earthquake in Western Australia's recorded history hit with a magnitude of 6.1. The epicentre was close to the town of Cadoux in the Wheatbelt region about 165 km (103 mi) north east of Perth, Western Australia. One person was injured and 25 building were damaged along with roads, railways and power-lines over an area of 4 ha (9.9 acres). The total amount of damage was around A$3.8 million.[21].

Collier Bay 1997[edit]

This earthquake, 10 Aug 1997, magnitude 6.3 just off the WA north coast, was the largest Australian earthquake since the magnitude 6.7 earthquake near Tennant Creek, in the Northern Territory, in January 1988.[9]

Burakin Swarm 2000–01[edit]

Located near Cadoux (but not on the same physical feature) the Burakin event was named the most significant seismic activity in 40 years.[22]

South of Albany 2001[edit]

This very large earthquake on 12 Dec 2001, magnitude 7.1 occurred about 1,000 km (620 mi) southeast of Albany. It was felt in Albany. It was an intraplate earthquake, as it occurred about 1,000 km (620 mi) north of the (constructive) boundary between the Indo-Australian and Antarctic plates.[9]

Kalgoorlie 2010[edit]

On 20 April 2010, a magnitude 5.0 earthquake occurred close to Kalgoorlie.[23] The quake caused damage to a number of hotels along Burt street in Boulder and an underpass also on Burt street collapsed. Work in the Superpit and many other mines around Kalgoorlie was also stopped.[24]

Lake Muir 2018[edit]

On 16 September 2018 a magnitude 5.7 earthquake occurred with its epicentre close to Lake Muir[25] in the South West region. On 13 October another earthquake with a magnitude of 4.7 was recorded[26] followed by a magnitude 5.4 earthquake on 9 November.[27]

Southwest region earthquakes[edit]

See also[edit]

Notes[edit]

  1. ^ Report of an earthquake felt in Perth on 4 Aug. 1849. The Inquirer, 8 Aug. 1849, p.3a - see also Report of an earthquake at Cossack on Sept. 10 1886 Western mail, 18 Sept. 1886, p.17
  2. ^ "Earthquake Image Gallery". Geoscience Australia. Archived from the original on 9 June 2009. Retrieved 1 January 2010.
  3. ^ a b Jones, T.; Middelmann, M.; Corby, N.; Academy of the Social Sciences in Australia; Institute of Australian Geographers; Geoscience Australia (2005). Heathcote, R.L.; Thom, B.G. (eds.). Natural hazard risk in Perth, Western Australia (PDF). Australian Government/Geoscience Australia/Bureau of Meteorology. ISBN 1920871438. Archived from the original (PDF) on 12 February 2014.
  4. ^ "Tennant Creek 1988 earthquake now Australia's biggest after Geoscience revises list". ABC News. Retrieved 14 July 2019.
  5. ^ Everingham, I.B. and Tilbury, L. (1971) Information on Western Australian Earthquakes which occurred during the periods 1894–1900 and 1923–1960 Australian Bureau of Mineral Resources Record 1971/80 – quoted as utilising newspaper sources by Gordon and Lewis 1980 p,213 – note also Everingham, I.B. and Tilbury, L. (1972) Information on Western Australian earthquakes 1849–1960. Royal Society of Western Australia. Journal 55, 90–96.
  6. ^ Gordon, F.R and J.D. Lewis (1980) The Meckering and Calingiri earthquakes October 1968 and March 1970 Geological Survey of Western Australia Bulletin 126 ISBN 0-7244-8082-X - Appendix 1 - page 213 Catalogue of Larger Earthquakes recorded in Southwestern Australia and in National archives ref CA 3539 Mundaring Geophysical Observatory, WA http://recordsearch.naa.gov.au/scripts/AgencyDetail.asp?M=0&B=CA_3539[permanent dead link]
  7. ^ "Seismicity of Western Australia: Seismic Monitoring". University of Western Australia. Retrieved 2 June 2019 – via pandora.nla.gov.au.
  8. ^ Estrada, B.; Clark, D.; Dentith, M.; Wyrwoll, KH (6–8 November 2015). Recognising intraplate seismogenic faults and associated seismic hazard: examples from Western Australia (PDF). Tenth Pacific Conference on Earthquake Engineering. Retrieved 2 June 2019.
  9. ^ a b c d e f g h i "Important Historical Earthquakes in Western Australia". University of Western Australia. Retrieved 2 June 2019 – via pandora.nla.gov.
  10. ^ Leonard, M; Darby, D; Hu, G (2007). GPS-geodetic monitoring of the South West Seismic Zone of Western Australia: progress after two observation epochs in 2002 and 2006 (PDF). Australian Earthquake Engineering Society 2007, Wollongong. Archived (PDF) from the original on 20 July 2008. Retrieved 2 June 2019. The Australian southwest seismic zone (SWSZ) is a north-south trending belt of intra-plate earthquake activity that occurs in the southwest of Western Australia, bounded by 30.5°S to 32.5°S and 115.5°E to 118°E. This is one of the most seismically active areas in Australia, with nine earthquakes over magnitude 5.0 occurring between 1968 and 2002, the largest of these was the M6.8 Meckering earthquake in 1968. Since the SWSZ lies as close as ~150 km (93 mi) from the ~1.4 million population of the Perth region, it poses a distinct seismic hazard.
  11. ^ See List of earthquakes in W.A. 1849–1924 (1929) - in - 'Results of rainfall observations made in Western Australia, p. 91-93, 'Results of rainfall observations made in Western Australia : including all available annual rainfall totals from 1374 stations for all years of record up to 1927, with maps and diagrams : and record of notable meteorological events : also appendices, presenting monthly and yearly meteorological elements of Perth, Broome and Kalgoorlie'. Australia. Bureau of Meteorology.Melbourne : H. J. Green, 1929.
  12. ^ Possible report in Butler, Jack. An elderly Aboriginal's recollection of an earthquake he experienced in the Ashburton district, 19 Nov. 1906 / Jack Butler and Peter Austin. Aboriginal history, Vol.10, no.1 (1986), p.78-84
  13. ^ "Earthquake in Kalgoorlie on 3 September 1991 forces rethink on long term future of underground operations". Gold gazette, 18 March 1991, p. 3
  14. ^ http://pandora.nla.gov.au/pan/25962/20040718-0000/www.seismicity.segs.uwa.edu.au/seismicity_of_western_australia/wa_historical/meeberrie.html
  15. ^ The Geraldton Guardian and Express, Tuesday 29 April 1941
  16. ^ Bureau of Mineral Resources Rept No. 132, by I.B. Everingham, 1968 – The Seismicity of Western Australia.
  17. ^ http://www.ema.gov.au/ema/emadisasters.nsf/83edbd0553620d8cca256d09001fc8fd/574856364a736fd9ca256d3300057d00?OpenDocument[permanent dead link]
  18. ^ http://www.ga.gov.au/hazards/earthquake/historic.jsp
  19. ^ "1970 Calingiri". Australian Earthquake Engineering Society. Retrieved 13 November 2018.
  20. ^ Cvetan Sinadinovski. "Seismicity in the South West of Western Australia" (PDF). Geoscience Australia. Retrieved 13 November 2018.
  21. ^ "Australia's worst earthquakes". Australian Geographic. 10 July 2012. Retrieved 12 November 2018.
  22. ^ http://pandora.nla.gov.au/pan/25962/20080712-0000/www.seismicity.segs.uwa.edu.au/welcome/seismicity_of_western_australia/wa_historical/the_burakin_swarm.html
  23. ^ Magnitude 5.2 - WESTERN AUSTRALIA United States Geological Survey 20 April 2010
  24. ^ Earthquake strikes Goldfields The West Australian 20 April 2010
  25. ^ "Magnitude-5.7 earthquake rocks southern WA". Australian Broadcasting Corporation. 17 September 2018. Retrieved 9 November 2018.
  26. ^ "Magnitude-4.7 earthquake rocks area surrounding Lake Muir in WA's Great Southern". Australian Broadcasting Corporation. 13 October 2018. Retrieved 9 November 2018.
  27. ^ Ben Anderson (9 November 2018). "Earthquake at Lake Muir shakes Perth and WA's South West". News Corporation. Retrieved 9 November 2018.