Quake Graphs

George Ure at Urban Survival has some interesting graphs put up showing a disturbing trend.
While the number of temblors with a 3.0 magnitude and above over the past several decades is going down:

the average magnitude is going up:

related - Swarm of Quakes Rattle Central California Overnight

"COSO JUNCTION - There's plenty of seismic shaking going on around the Golden State.
In Central California, six earthquakes bigger than a 3.0 have hit the same spot within the past three days.
The strongest, a 3.8 hit, this morning around 1am, centered in Coso Junction.
And near the US/Mexico border, a 3.4 magnitude quake. This one hit last night around 10pm in Ocotillo."

Is The Yellowstone Caldera Calling?

Earthquakes beget earthquakes near and far

"University Park, Pa. -- Earthquakes not only shake up the local area but they also increase the rate of earthquake events locally and at a distance. The answer to how this happens may be in the laboratory, according to a Penn State researcher."We have learned a lot since the Landers earthquake in the Mojave Desert in 1992," says Chris Marone, professor of geosciences. "We learned that earthquake triggering happens a lot more than we thought. The mechanism is not well understood."