The San Andreas fault at Cajon Pass

The San Andreas fault at Cajon Pass; this view is from one of our USGS-Caltech SoSAFz sites that I upgraded to improve low-latency GPS performance for use in the prototype earthquake early warning system. The red arrows point to the trace of the fault where it passes up Lone Pine Canyon towards Wrightwood, California in the distance. Los Angeles is behind (south, or to the left of) the San Gabriel Mountains in this photo. Click the small image below to see the full-res annotated photo.

What happens when...?

Sometimes a question is asked that you have never heard before; it challenges you to think differently about how to explain something to the public or to a student in clear terms, without jargon. I love it when that happens; a recent result is this interesting 'Critical Opalescence' Scientific American blog article by George Musser -- @gmusser -- http://blogs.scientificamerican.com/critical-opalescence/2013/11/11/what-happens-to-google-maps-when-tectonic-plates-move/