Nevada quakes continue. Are they foreshocks rather than aftershocks?

On Feb. 21, 2008 there was a moderately powerful earthquake of 6.3 near Wells, Nevada. Naturally that was followed by many aftershocks. But now geologists are wondering if something unusual may be underway, especially as the quakes seem to have migrated toward populous Reno, Nevada.

Sometimes moderately large quakes are foreshocks of a really big one.

Reno urged to prepare for worse as earthquakes continue. By Martin Griffith. Associated Press.

Update. April 30. Scientists seek clues as Reno earthquakes keep shaking. By Sandra Chereb. Associated Press.

Nevada has hundreds of mountain ranges. Most of them are classic fault block uplifts. There are thousands of active faults.

Monitor earthquakes around the world as they happen at USGS World Earthquake page.

Note: most of southern Idaho (where I live) felt the Wells quake quite distinctly.