4. What were the observations that Mohorovičić made that led to his discovery of the Mohorovičić Seismic Discontinuity?(1 point)

Question

Responses

earthquake waves travel into the ocean
earthquake waves travel into the ocean

earthquake waves were refracted at a certain depth under the surface of the earth
earthquake waves were refracted at a certain depth under the surface of the earth

all earthquake waves travel at the same speed

Answer 1

The correct observation that led to Mohorovičić's discovery of the Mohorovičić Seismic Discontinuity is:

earthquake waves were refracted at a certain depth under the surface of the earth.

This observation indicated a change in the properties of the Earth's materials at that depth, marking the boundary between the Earth's crust and the underlying mantle.