Question

Earthquake foci (Focus, singular) are....

Answer 1

Answer:

3. depth of 50 - 200 miles.

Explanation:

• The foci is the focus spot down below the epicenter where the earthquake occurs in the crust and upper mantle. The presence of a subduction zone where the plate collides with one another.

• The earthquake range from 0-800 mile of depth the deep foci earthquakes are of range 50 to 300 miles as the stress regimes are deeper downwards like a dip down.

• This zone is also called as the dipping seismic or the wadis Benioff zone. As the san Andreas fault has a shallow depth of about 20 m depth which is considered the deepest.

Answer 2

The answer is the 3rd choice