Question

question 20 of 25
what causes seafloor spreading?
a. instability in the speed and direction of earths ocean currents
b. circular currents due to thermal energy changes in earths mantle
c. seismic waves moving upward in earths lithosphere
d. pressure pushing upward due to the heat in earths core

Explanation:

Seafloor spreading is caused by convection currents in the Earth's mantle. These are circular currents due to thermal energy changes in the mantle that drive the movement of tectonic plates and create new oceanic crust at mid - ocean ridges.

Answer:

B. Circular currents due to thermal energy changes in Earth's mantle