Sir Bedevere: ...and that, my liege, is how we know the Earth to be banana shaped.
King Arthur: This new learning amazes me, Sir Bedevere. Explain again how sheep's bladders may be employed to prevent earthquakes.
Posted on 01/04/2007 10:49:04 AM PST by blam
Coal Mining Causing Earthquakes, Study Says
Richard A. Lovett
for National Geographic News
January 3, 2007
The most damaging earthquake in Australia's history was caused by humans, new research says.
The magnitude-5.6 quake that struck Newcastle, in New South Wales, on December 28, 1989, killed 13 people, injured 160, and caused 3.5 billion U.S. dollars worth of damage (Australia map).
That quake was triggered by changes in tectonic forces caused by 200 years of underground coal mining, according to a study by Christian D. Klose of Columbia University's Lamont-Doherty Earth Observatory in Palisades, New York.
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, Klose said.
All told, he added, the monetary damage done by the earthquake exceeded the total value of the coal extracted in the area.
Klose presented his findings at a meeting of the American Geophysical Union in San Francisco, California last month.
Heavy Burden
The removal of millions of tons of coal from the area caused much of the stress that triggered the Newcastle quake, Klose said. (Related: "Mountaintop Mining Raises Debate in Coal Country" [January 13, 2006].)
But even more significant was groundwater pumping needed to keep the mines from flooding.
"For each ton of coal produced, 4.3 times more water was extracted," Klose said.
Other mining operations, he added, sometimes require as much as 150 tons of water to be removed for each ton of coal produced.
"So this is on the low end," he said. Human-Caused Quakes
Coal mining isn't the only human activity that can trigger earthquakes.
Enlarge Photo
Klose has identified more than 200 human-caused temblors, mostly in the past 60 years. "They were rare before World War II," he said.
Most were caused by mining, he said, but nearly one-third came from reservoir construction.
Oil and gas production can also trigger earthquakes, he added.
Three of the biggest human-caused earthquakes of all time, he pointed out, were a trio that occurred in Uzbekistan's Gazli natural gas field between 1976 and 1984 (map of Uzbekistan).
Each of the three had a magnitude greater than 6.8, and the largest had a magnitude of 7.3.
Human-triggered earthquakes are particularly dangerous, Klose said, if they occur in seismically inactive areas.
That's partly because people aren't prepared for them. But also, he said, "regions that are naturally inactive are very trigger-sensitive, because stress has built up over long periods of time."
Expensive Implications
Klose's presentation drew considerable attention from the assembled geophysicists, who wondered if there were ways to reduce the risk by altering mining practices.
"One way would be to find a way that doesn't reduce the water in the mine," Klose said.
But as far as he knows, mining engineers aren't examining this, because they are currently unaware of the earthquake risk.
The danger is also relevant to proposals to sequester carbon dioxide by injecting it into geologic formations deep underground where the gas cannot escape and contribute to global warming.
"That alters stress in the crust [too]," Klose said, adding that the risk of earthquakes should be taken into account in planning the locations of such facilities.
Basically, he said, "don't put the injection fields close to large cities."
The research could also have an impact on earthquake-insurance premiums, André Unger of the University of Waterloo, in Ontario, told National Geographic News by email.
The precise method by which premiums are calculated is a deeply guarded trade secret, but they appear to be based on a region's historical earthquake risk—"a purely statistical methodology," he said.
The new finding indicates that other factors are now at work, he said.
Furthermore, Unger noted that underground carbon sequestration might be a mixed blessing from insurance companies' points of view
A carbon-sequestration plan could reduce the risk of some types of damage (such as from hurricanes, which some scientists say are being strengthened by global warming), while increasing the risk of others, like earthquakes.
Good, something else to worry about. There goes the price of coal.
"caused by humans"
Time for us to get off this planet. There must be what ,100 Billion more ants then humans but we get all the fault.
Does sneezing people cause the wind to blow more violently?
Another good reason to build nuclear power plants.
I'm sure the Queen P and her Nancy Boys will get right on that...for the children.
Fortunately we can use sheep's bladders to prevent earth quakes.
The enviro-wacko's should re-deploy to Neptune or Uranus.
Then West Virginia and Pennsylvania should be imploding anytime now.........
The enviro-wacko's should re-deploy to Neptune or Uranus.
____________
I vote Neptune. It's further away.
I know this about Pittsburgh PA. The city is sitting on top of old played out coal mines and every now and then an entire neighborhood will suddenly fall in. It might amount to only a few feet since the mines are dug out only as much as the coal seam was thick, but that can be highly disruptive to common brick structures. Lots of old brick buildings, lots of former coal seams.
Sir Bedevere: ...and that, my liege, is how we know the Earth to be banana shaped.
King Arthur: This new learning amazes me, Sir Bedevere. Explain again how sheep's bladders may be employed to prevent earthquakes.
You can tell this is written by a leftist evironut by this statement.
Calculating a real value for this would require calculating the cost of replacing the coal with another energy source (or importing coal), which in the early days of the mine would likely have been expensive and unthinkable at the time.
Klose has identified more than 200 human-caused temblors, mostly in the past 60 years. "They were rare before World War II," he said.
What are his criteria for making this statement? Perhaps it could be any temblor that occurs in vicinity to a mine maybe?
Klose's presentation drew considerable attention from the assembled geophysicists, who wondered if there were ways to reduce the risk by altering mining practices.
"One way would be to find a way that doesn't reduce the water in the mine," Klose said.
But as far as he knows, mining engineers aren't examining this, because they are currently unaware of the earthquake risk.
I can’t imagine how you could mine anything with out dewatering. Even mining in mountains located in arid areas requires dewatering to some degree.
But maybe we should simply stop mining altogether and just recycle.
Nay!!!
Yeah, so does cow flatulence. I'm getting really sick and tired of these phoney baloney "studies" and "reports" by people who can barely spell "scientist", much less be one!
Isn’t this caused by the mine being on fire?
I'm not buyin' it. Not for one minute.
Once the mine is mined out a fire is unlikely. An explosion is possible, but usually the mine is near the surface and the ground gives way under the basement.
Plate Tectonics causes Volcanoes and Earth Quakes.
OMG, that is about the most stupid premise EVER.
Let this bozo CAUSE an earthquake. Let's see how well he does and measure it.
Back up your dumb assertion, Mr. Scientist.
Isn’t this caused by the mine being on fire?
Wrong side of the state.
This statement is idiotic. Regions that are naturally inactive are not under great stress. That is why they are naturally inactive. If they were under great stress and very trigger-sensitive they would be not be naturally inactive.
I haven't heard of entire neighborhoods falling in, but if they start, can they start with Homewood?
Well, that was just to get some sympathy. But sometimes one or two basements will open up and the whole house can go in. Happens a lot, once or twice while was there, but they don't usually drop out of sight, just enough to ruin a brick wall or a concrete foundation.
Nonsense. Coal mining built that entire area. If the buildings and infrastructure were worth more than all the coal they've ever pulled out, it never would have made economic sense to build them in the first place.
So what about pumping oil and water? I could see man's activities being responsible for sinkholes, but not earthquakes.
A city is itself a goldmine. The value of the city would not depend on the mining industry alone but on the usual economic activity. Mining might be the kickstart, but the city can keep going and growing forever after the mines are played out.
I'll bet that he can prove, with a little more funding, that Wal-Mart and tobacco companies cause earthquakes too.
Liberals are the most self-loathing group of frightened lemmings...
Sheesh.
That's subsidence; how did tectonic shift and subsidence become married?
This idea doesn't pass the smell test.
(Note: While it was a Very Bad Thing, only one life was lost in the collapse, and that to a heart attack as he was trying to evacuate.)
But the point is the same. Mining can cause, and has caused earthquakes.
There may have been as many earthquakes before WWII as after, bu they may have been in remote areas. How many seismographs were in use before WWII?
I have lived in Western PA all my life and never heard of "an entire neighborhood" caving in. Yes, individual houses have had problems... for the most part cracked foundations that can be expensive to fix. Occasionally, a house is damaged so bad it must be condemned. There is mine subsidence insurance available and you can check with the state to find out if there is an old mine under your property.
A more serious problem is fires in abandoned mines which has on occasion caused entire neighborhoods to be condemned due to the toxic fumes that can enter buildings. Putting out mine fires very expensive and if possible, they allow them to burn themselves out which can take decades.
While I lived there a house fell in and my neighbor said it happens all the time. Of course you have to build over an old uncharted mine, which is getting less and less likely as the town expands.
But that's not the case here. Coal is by far the dominant industry, there.
There was a quake under my garage a couple days ago. Seriously, 2.2
Felt it, a lot of people felt it. Epicenter was 8 miles down, directly down. No mining, no drift mines, not even a placer mine right here. I just mention that because a 2.2 is not usually thought important enough to mention. The dog is still kind of spooked.
Now my take - breathing causes death so quit now!
I would be willing to say that extensive mining can cause a subsidence, but I think 'earthquakes' is giving way to much credit to the works of man.
I'm waiting for the report linking cow flatulence to earthquakes and/or tsunamis.
Write to the Department of the Interior for a grant.
Oh, yeah I believe this.
That was good...
See post #34.
WCF makes a compelling case that sneezing "could" cause earthquakes and if a simple sneeze could do it, how much more carnage is the result of pernicious cow flatulence?
I urge you to pursue this and apply for grants to throughly investigate this possibility. There is no point in letting WCF get all the cash.
Personally, I'm investigating the potential of basketball kicking of major tremors with all of the stress of bouncing balls and 200 pound players repeatedly jumping upon the fragile crust of the earth. Preliminary figures show that an excess 500,000 tons of stress are placed on the crust per game and I figure that a grant for further research should be worth at least a dollar per ton. We must do this before an NCAA Tournament ends life as we know it.
Walk softly, and carry a big grant.
There is somewhat of a difference between sink holes and undermining tectonic plates. /sarc
"She turned me into a newt!!"
mumble mumble mumble
"I got better!"
Apples and oranges. Explosions, collapses, etc., can cause Richter readings. It doesn't have to be an EARTHQUAKE.
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