Figure 1, Coal Mine (Geographical, 2007)
Figure 1, Coal Mine (Geographical, 2007)
Figure 2: Location of Earthquake (Bidgee, 2008).
Figure 2: Location of Earthquake (Bidgee, 2008).


























Human Actions: Newcastle Earthquake by: Vanessa Schnose
Natural disasters create massive amounts of damage that is often inevitable. There is often very little that humans can do to prevent their occurrence. However, in some cases humans are responsible for creating natural disasters. Research shows that this is true of some of the earthquakes that have shaken the global community. In the past 60 years, at least 200 earthquakes have resulted from human activity (Lovett, 2007). On December 28, 1989 the stress of human interference shook Newcastle,Australia (Geographical, 2007).
The Newcastle earthquake was the most devastating earthquake in Australia’s history. The earthquake had a magnitude of 5.6. The earthquake took place just 125 kilometers outside of Sydney, but most of the damage was felt in Newcastle (Geographical, 2007). As Figure 2 shows, most of the destruction was isolated to New Castle, but moderate shaking was felt as far away as Canberra (Bidgee, 2008). This earthquake took place after the infrastructure of the Newcastle Worker’s Club, a coal mine, failed to possess stability (University of Western Australia, 2010). The seismic activity was created by underground mining. Miners had been mining beneath Newcastle for 200 years before the quake struck. Over time, more than two billion pounds of coal were extracted from the ground. The stress from the removal of coal was one cause that contributed to the seismic activity that led to the Newcastle earthquake (Lovett, 2007).
The removal of coal was not the sole cause of the earthquake. Groundwater pumping also contributed to the seismic activity that occurred during the Newcastle earthquake. More than four times as much water was removed from the ground as coal. Often times, mining requires one hundred and fifty times more water than coal to be extracted from the ground in order to mine successfully. Still, four times more water than coal, contributed significantly to the stress build up that led to the Newcastle earthquake (Lovett, 2007). The withdrawal of fluid can alter the location, and amount of stress. This can create fractures that contribute to earthquakes (Chilingar, 2000). This is often a factor in earthquakes caused by petroleum production. It happened to also contribute to the Australian earthquake with the removal of water (Lovett, 2007).
Dr. Klose, a professor at Colombia University provides proof for the assertion that the Newcastle earthquake was triggered by the removal of coal. However, there are some who are skeptical of Dr. Klose’s claims. His critics challenge the claim that mining and the removal of water were the only possible causes for the earthquake. They do not dismiss his research entirely, but suggest that more research should be done. Since his critics do not offer an alternative, Dr. Kloses’s claims should at least be considered (AAP, 2007). Dr. Klose does not claim that the earthquake was caused by seismic activity associated with most earthquakes. Therefore, it is not possible to determine what type of faulting was involved. Rather, he concludes that the Newcastle earthquake was triggered by geoengineering. He claims that geoengineering altered the stress placed on the earth’s crust. The primary source of evidenced used by Dr. Klose is a geomechanical crust model, which shows how the mining of coal and injection of fluids triggered the earthquake (Klose, 2006).
The damage that resulted from humans removing coal and water from beneath Newcastle is astonishing. The Newcastle earthquake was the deadliest earthquake in Australia’s history. The earthquake killed 13 people. (Lovett, 2007).By following this link it is possible to view the extent of the damage both on Newcastle’s citizens and on the infrastructure of Newcastle.
http://www.abc.net.au/news/video/2009/12/28/2781304.htm (ABC, 2009). The eyewitness descriptions in the video describe the threat to human life created by the earthquake. The thirteen fatalities are especially significant because earthquakes that threaten life are very rare in Australia. In Australia’s history only three earthquakes have resulted in fatalities. The fatalities from the other two earthquakes combined, York Peninsula Earthquake of 1902 and the Gayndah Earthquake of 1935, equal less than one third of the fatalities caused by the Newcastle Earthquake. It is unfortunate that human lives had to be lost in order to discover the dangers of that type of mining g activity (University of Western Australia, 2010).
The economic damage of the earthquake cost more than the profits produced by the mining that triggered the quake. The damage created by the earthquake was worth 3.5 billion dollars (Lovett, 2007). To put this in perspective, the damage of the Newcastle earthquake was 26% of Australia’s Gross Domestic Product growth between 1967 and 1999. The cost of the Newcastle earthquake of 1989 accounted for 94% of the damage of all of Australia’s earthquakes and 13% of all of Australia’s natural disasters within that time frame (Klose, 2006). It is sobering to imagine that this level of destruction was preventable. The Newcastle earthquake created significant damage because it was unexpected. Figure1 shows an image of a typical mine. This image makes the vulnerability of the miner during ground shaking easy to imagine (Lovett, 2007). The infrastructure was not engineered to withstand earthquakes (Lovett, 2007).
Fortunately, as with most natural disasters, the Newcastle earthquake presented an opportunity to learn. The Newcastle earthquake encouraged the Australian Standards Association to modernize the Australian Earthquake Code, AS2121. In 1993 the Australian Loading Code was published. The Australian Earthquake Engineering Society was also created in response to the Newcastle Earthquake (Lee, 2003). These organizations devise mitigation strategies to prevent similar destruction as what was caused by the Newcastle earthquake. The Newcastle Earthquake caused a very significant amount of damage when considering the amount of energy that was released. The Newcastle earthquake only had a magnitude of 5.6. Still, it caused more financial damage and loss of life than the 6.8 Meckering earthquake of 1968, the 6.9 Bass St. earthquake of 1892, or the 7.3 Meeberrie earthquake of 1941. The damage of the Newcastle quake could have been minimized if more mitigation strategies were implemented (University of Western Australia, 2010). Although the members of the Newcastle community and the concerned members of the global community cannot go back in time and reverse the human errors of the past, they can learn from the past and use mitigation strategies in the future. These mitigation strategies offer hope for the prevention of future man- made natural disasters.


Sources
AAP. (2007). Newcastle Earthquake Study Far-fetched. The Australian. Retrieved March 8, 2010, from htto:www.thequstralian.comau/news/nation/Newcastle.


ABC News. (December, 2009). ABC Video. Flashback:
The Newcastle Earthquake. Retrieved January 17, 2010, from http://www.abc.net.au/news/video/2009/12/28/2781304.htm

Bidgee (2008). Image of Newcastle Earthquake Based on Mercalli Intensity Scale.
Wikimedia Commons. Retrieved January 17, 2010. from http://commons.wikimedia.org/wiki/File:1989_Newcastle_earthquake_map.png

Chilinagar, G., Leonid, K., Endres, B., & Robertson, J. (2000). Gas Migration: Events
Preceding Earthquakes. Houston: Gulf Publishing Company.

Geographical. (2007) Australia Earthquake Triggered by Mining.
Geographical Magazine. 79 (4). Retrieved January 1, 2010, from Gale Group Inc. http://www.global.factivia.com.library.csupomona.edu/ha/default.aspx

Klose, C.D. (2006).
GC44 A-01 Scientific, Engineering and Financial Factors of the 1989 Human Triggered Newcastle Earthquake in Australia. Retrieved March 8, 2010, from http://www.agu.org/meeting/fm06/fm06-sessions/fm_GC44A.html.

Lee, W., Hiroo, K., Jenning, P.C., & Kissinger, C., (2003).
International Handbook of Earthquake & Engineering Seismology (Part B). Amsterdam: Academic Press.

Lovett, Richard A. (2007). Coal Mining Causing Earthquakes, Study Says.
National Geographic News. Retrieved January 15, 2010, from http://news.nationalgeographic.com/news/2007/01/070103-mine-quake.html

University of Western Australia. (January, 2010).
Seismicity in Australia. Seismicity in Western Australia//. Retrieved January 15, 2010, from http://www.seismicity.see.uwa.edu.au/welcome/seismicity_in_australia#NSWeq