Earthquakes are not scattered at random: they trace the seams between tectonic plates. Each circle is one earthquake, sized by magnitude and coloured by depth, and the thin line is the PB2002 plate-boundary model. Click a circle for details, use the layer control to isolate a depth band, and use the ruler to measure distance along a fault.
Data: USGS Earthquake Hazards Program 30-day M4.5+ feed. Plate boundaries: Bird (2003), PB2002, via fraxen/tectonicplates. Built with R Markdown and Leaflet.