Question: what is the difference between shallow and deep focus earthquakes?
Answer: Shallow earthquakes are between 0 and 70 km deep; intermediate earthquakes, 70 - 300 km deep; and deep earthquakes, 300 - 700 km deep. In general, the term "deep-focus earthquakes" is applied to earthquakes deeper than 70 km. ... Previously, all earthquakes were considered to have shallow focal depths.