Where the Fault Lies within a Plate
Major faults occur at the point where two tectonic plates collide. But they can also exist within plates, as the New Madrid fault does in the middle of North America. Scientists are still unsure what powers these intraplate earthquakes; they may result from some combination of forces, such as the removal of glacial sheets after the last ice age or the drag from the fluid mantle underneath the plates. Earthquakes from such faults can be quite powerful and deadly. “Perhaps the most damaging earthquake in Australia’s recent history was in Newcastle in 1989, when a quake measuring 5.6 killed 13 people and left a damage bill of billions of dollars. It was in the middle of the continent,” recounts Seth Stein of Northwestern University. China and northern Europe may also be good places to investigate such activity.
Note: This article was originally printed with the title, "Rumble Off".