Scientists believe that some other planets in the universe might have a geologic structure similar to Earth’s, including a mantle and an outer layer made of plates. Imagine that scientists have found a planet with an outer layer divided into plates made of hard, solid rock, but the mantle below the plates is made of hard, solid rock instead of soft, solid rock as it is on Earth.

Do you think plate motion would take place on that planet? Why or why not? (Use the words in the Word Bank if it helps you answer the question.)