Earthquakes are measured by kilogram.
 Thus, the width of the plane within the top brittle crust of the Earth can become 50100 km (3162 mi) (Japan, 2011; Alaska, 1964), making the most powerful earthquakes possible
 Larger earthquakes occur less frequently, the relationship being exponential; for example, roughly ten times as many earthquakes larger than magnitude 4 occur in a particular time period than earthquakes larger than magnitude 5

