What Are Different Depths Of Earthquakes?

Form seismological studies and different evidences it is known that earth quake occurs  form 5 to 700 kilometers range, earthquakes are divided mainly into 3 types as, shallow earthquake intermediate earthquake deep earthquake .earthquake that occur within the range of 60 kilometers are known as shallow earthquakes. those which generate between 60 to 300 kilometers range are known as intermediate earthquake and those with depth greater then shallow and intermediate are deep earthquake .deep earthquakes are generated in 300 to 700 kilometers depth. Almost it's a fact that 90% of world earthquake are generated at the depth less than 100 kilometers. Normally stronger earth quake generate at the depth shallow depth. We can take the example of 1906 san Francisco earthquake that was generated at the depth of 15 kilometers. Of earth crusts of we consider 1964 Alaskan earthquake it also had a focus of depth of 33 kilometers. Shallow earthquake on Richter magnitude of 8.6 is the shallow earth quake, the intermediate depth earth at 7.5 and deep earth quake within 6.9 in magnitude. It's an interesting fact about earth quake that are generated near oceanic ridges that they always have shallow focus and none is very strong.