My latest Mind and Matter column from the Wall Street
Journal:
Earthquakes are natural disasters. However much culpability there
is afterward about the building standards that may have worsened
the death toll or the response of the emergency authorities, nobody
is to blame for the actual shock.
At least, not normally. An exception is the phenomenon of "induced
seismicity," whereby human activity such as geothermal energy
projects, mining, gas drilling or the filling of reservoirs
apparently sets off swarms of very small earthquakes where there
are susceptible geological faults and in certain kinds of
underlying rock.
A recent report from the U.S. Geological Survey concludes, for
example, that a nearby shale gas well probably caused a swarm of 43
very small earthquakes (largest magnitude, 2.8) in Garvin County,
Okla., last January. A few hours before the quakes began, the well
had ceased hydraulic fracturing or "fracking": that is, injecting
high-pressure water into the ground to crack deep rocks.