from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The frequency or magnitude of earthquake activity in a given area.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. factor of how seismic a region is. How prone it is to earthquakes.
from The Century Dictionary and Cyclopedia
- n. The ratio between the number of earthquakes in a region and the area of the region.
Sorry, no etymologies found.
Now, here is the whole world and the seismicity, meaning: who is likely to experience earthquake activity?
Forty years later, engineers now know what kind of seismicity to expect in Oregon.
The other kind of seismicity associated with the volcano occurs after the initial shaking, but before the eruption, "when you have fluids and gases moving through the edifice and cracks and fault zones [and] you get this characteristic ringing and a resonance," said study team member Philip Benson of the University College London.
Unfortunately, many U.S. reactors were built decades ago when we knew less about flooding, seismicity and other threats.
The Oklahoma Geological Survey reported on its website that it located 1,047 earthquakes in the state in 2010, adding, "the frequency of earthquakes has temporarily increased in Oklahoma, but these earthquakes do not appear to be inconsistent with what might be called normal seismicity for Oklahoma."
"It is confirmed and established that injection wells can induce seismicity," said Scott Ausbrooks, a geologist for the Arkansas Geological Survey.
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.
Whatever the rights and wrongs of dam building, induced seismicity is part of a trend affecting human culpability in general.
As a colleague of mine says, Hayward is a "high anxiety" fault, partly because it has ongoing seismicity, and secondly because we have made people aware that it is likelier to have a larger earthquake.
In a 2008 paper, four researchers from Columbia University reported that “Indian Point is situated at the intersection of the two most striking linear features marking the seismicity and also in the midst of a large population that is at risk in case of an accident at the plants.”