Where do the Mountain Aquifer and Coastal Aquifer occur?

If scientists only detect p waves in a certain layer of earths interior what does that tell us?

What did the pattern of earthquakes in the wadati-benioff seafloor zones show scientists? a.) earthquakes occur where the ocean floor reaches its highest temperatures. b.) many earthquakes take place 700 kilometers below the seafloor. c.) slabs of ocean floor return to the mantle in subduction zones. d.) ocean - trenches cause earthquakes.

What does 2[tex] {2}^{ - 4} \times {2}^{ - 2} [/tex]