Chapter 27, Problem 6TE

To determine

Whether present-day continents are a permanent feature on our planet.

Answer to Problem 6TE

The present-day continents are not a permanent feature on our planet.

Explanation of Solution

According to plate tectonics theory, the Earth's crust is in constant movement and rearrangement. What we see under an ocean at present could be a high plain a million years from now. Also, it might have been a mountain top millions of years ago. Again there are volcanoes that could form and fill in basins and earthquakes that could split the Earth or push it back together. Or even rock slides change the shape of the Earth.

All these phenomena make changes in the Earth lithosphere that would further result in gradual changes in the Earth. This makes the present-day continents a temporary feature on our planet. As the continents themselves will always exist, they have previously and are currently shifting and making new shapes and moving through the shifting of the tectonic plates under the Earth

Conclusion:

Therefore, present-day continents are not a permanent feature on our planet.