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本帖最后由 PEW 于 2009-11-17 22:10 编辑 6 ?) N9 |: Y* {: t
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Alberta scientists probe possible human causes of earthquakes
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0 `& u( e; w/ A/ s) s7 D4 eBy Tamara Gignac , Calgary HeraldNovember 13, 2009[/b]
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7 L8 \ G- }0 j; w. s( \CALGARY — Could oil and gas exploration — or the burial of climate-changing carbon dioxide deep underground — trigger earthquakes in the normally calm crust of Alberta?4 T) F4 j$ Z6 `( B) o- q
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7 y; } p8 I( y) n8 F" Y B! LNobody knows for sure but a team of researchers from the University of Calgary plans to find out.
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Most tremors in Alberta are too small to notice but sizable earthquakes do occur — as in 2001, when a 5.4-magnitude event rocked the northern Dawson Creek area and was felt as far south as Edmonton.
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* U% o$ {% Z- U' |# p4 yScientists at the U of C's geoscience department hope to learn more about what causes these poorly understood subterranean movements by installing a series of monitoring devices across Alberta.
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Earthquakes occur naturally but can also be human-induced, Dave Eaton, U of C head of geoscience, said Friday.
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He said he wants to know more about the impact of the oil and gas industry on seismic activity — and better understand the potential seismic effects of underground CO2 storage, a largely untested technology seen by many governments as a magic bullet to arrest greenhouse gas-induced climate change.+ b$ s" |0 m) ^& ~. z7 |9 @% O: a1 q
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The Alberta government has promised $2 billion toward carbon capture technologies, with the federal government earmarking $1 billion toward a clean-energy fund.8 X* f& W3 r) U6 n6 S
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Dave Eaton, a geophysics professor, is looking for links between oil and gas activity and earthquakes in Alberta. (CBC)( u; h% F; `5 E7 M1 E
* a `6 T( {+ r2 L"A large earthquake in Alberta would be a rare event, but even one with a magnitude of five or six would be a concern for certain types of storage facilities like CO2," said Eaton. He was in Priddis, just south of Calgary, to launch one of nine monitoring devices that will send information to an early warning data centre in Ottawa.- F1 k6 h' w2 t% \2 q' W
& v8 D N% ]+ ?$ \The project is the second of its kind launched this year in Alberta. Last June, scientists from the University of Alberta deployed 11 high-tech seismometers in farmers' fields and other locales in a bid to find out when and where a quake happens and where a fault may be located.
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The U of C's stations, however, can send data over the Internet, where it will be accessible to people all over the world.' N7 p9 j) ^3 F8 ` @- S
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The study could have a big impact on the emerging carbon-capture industry in the province. Alberta has set aside $2 billion to fund such projects.1 h* _& }4 ^4 Y( U8 L' w0 b
& s- K& Q( [; r"There's no proof right now of any causal link between CO2 injection and earthquakes, but that's one of the reasons we would like to investigate it more," Eaton said. "We need to be very careful and aware of all the earthquake risks, especially when we are contemplating these sorts of really long-term storage of materials inside the earth."
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Little is known about the possible connection between earthquakes and carbon capture, said John Harper, a geologist with the Geological Survey of Canada. . [5 w3 t. {/ G1 T, n3 k: D _
3 J3 D: R. `. s! z$ A2 l"Not a lot of research has been done relative to carbon capture and storage and earth movements so it is the kind of research that is extremely valuable," he said.+ P% L. y" e% e3 U0 A6 Q) ~
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Eaton is also interested in what's happening deep underground.
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"We are also hoping to understand better the deep geology of this region and some of the forces that cause the North American plate to move."' W3 g" z6 Z/ p9 ~, ?
& Y7 D) u f+ N9 {* o0 y4 }The University of Alberta in Edmonton also has earthquake research stations, but the University of Calgary's stations will be online, accessible through the Geological Survey of Canada. Researchers have to go to the U of A stations in person to collect the information.
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