Question: A tectonic plate that is being subducted along much of its boundary tends to move _________ a tectonic plate that is not being subducted.
a) slower than
b) faster than
c) the same rate as
d) over
slower than
To answer this question, we need to understand the concept of subduction and its effect on tectonic plate movement.
Subduction occurs when one tectonic plate is forced beneath another plate at a convergent boundary. When a plate is being subducted, it is typically pulled downward into the Earth's mantle by the force of the descending plate. This process of subduction leads to a change in the movement of the subducting plate compared to a plate that is not being subducted.
Now, let's analyze each option:
a) Slower than: When a tectonic plate is being subducted, it is dragged downward into the mantle. Since it is being pulled and pushed down, it will typically move at a slower rate compared to a plate that is not being subducted.
b) Faster than: As explained earlier, subduction involves the downward movement of a plate. Therefore, a plate being subducted would not generally move faster than a plate that is not being subducted.
c) The same rate as: This option is unlikely as the process of subduction significantly affects the movement of a tectonic plate. Therefore, a subducting plate typically does not move at the same rate as a plate that is not being subducted.
d) Over: "Over" does not describe the movement of a subducting plate but instead implies gliding or moving on top of another plate. This option does not accurately explain the movement of a subducting tectonic plate.
Based on the explanations above, the correct answer would be:
a) Slower than