As many of you are aware, the Earth's crust is cracked like an eggshell and moved around by convection (heating -cooling circulation like peas boiling in a pot) in the mantle. The majority of earthquake and volcanic activity occurs in these regions. Thus the plate boundaries can be traced with a degree of certainty, such as shown below:
USGS - image source
(It ought to be noted that the Indo-Australian plate is actually two plates)
Notice on the map, the Hawaiian Islands - which are a volcanic hotspot, away from a plate boundary... this is somewhat, but not totally analogous to intraplate earthquakes. Essentially, they are earthquakes that occur away from plate boundaries - in places such as Hawaii (as occurred recently), and other areas away from volcanic influences such as Australia and China, a very famous example is the New Madrid Fault Zone in the US.
Berkeley - mainly about the New Madrid and Charleston quakes
AGU - a south west Pacific example