I just released a small update to the Catfood Earth Beta adding a layer for earthquakes.
The layer uses the USGS feed for earthquakes over magnitude 2.5 in the past day.
Catfood Earth displays an accented circle over the epicenter of the earthquake. The size of the circle is proportional to the magnitude. You can customize the fill and accent colors. It's also possible to show earthquakes from the past hour up to the past 24 hours.