The most damaging earthquake in Australia’s history was caused by humans, new research says.
That 1989 quake was triggered by changes in tectonic forces caused by 200 years of underground coal mining.
The removal of millions of tons of coal from the area caused much of the stress. A more significant cause was groundwater pumping needed to keep the mines from flooding. For each ton of coal produced, 4.3 times more water was extracted – sometimes as much as 150 tons of water removed for each ton of coal produced.
The quake wasn’t enormous, but Australia isn’t generally considered to be seismically active and the city’s buildings weren’t designed to withstand a temblor of that magnitude.
The monetary damage done by the earthquake exceeded the total value of the coal extracted in the area.