At approximately 3:25 AM local time, a fairly significant earthquake hit Northern California. I had just woken up in Berkeley, and was annoyed that my neighbor’s large dog was barking when things started shaking. The epicenter of the quake, near Napa, California, is about 30 miles from me as the crow flies (see map below), so the effects were comparatively gentle here – a normal (for California) minor shaker. An Instagram User in Santa Rosa, about 15 miles from the epicenter, posted a video of his chandelier swaying, demonstrating the back-and-forth motion of the later moments of the quake. But 6.0 on alluvial soil can lead to real damage. A look at the map showing the epicenter reveals that it is near the mouth of the Napa River, on what should be alluvial soil. It appears be quite close to Napa Airport, in an area that has some commercial and industrial facilities. The City of Napa is nearby and is comparatively densely populated. I wouldn’t expect...(Read Full Post)