The Moving Plates

The video discusses the initial skepticism towards Wegener's theory of continental drift due to the lack of explanation for how continents could move through the ocean floor. In the 1960s, scientists discovered undersea mountains and ridges, leading to the understanding of seafloor spreading and the development of the plate tectonics theory. This theory suggests Earth's surface is divided into tectonic plates that float and move, causing various geological processes.

Why did many scientists initially reject Wegener's theory of continental drift?

• It lacked an explanation for how continents could move through the ocean floor.

• It was too complex to understand.

• It contradicted the theory of evolution.

• It was not supported by any geological evidence.

What is a significant feature of mid-ocean ridges?

• They are the deepest parts of the ocean.

• They are the largest mountain chain in the world.

• They are completely inactive geologically.

• They are formed by the collision of tectonic plates.

What process occurs at rift valleys along mid-ocean ridges?

• Earthquake prevention

• Tsunami generation

• Mountain formation

• Seafloor spreading

What does the theory of plate tectonics propose about Earth's surface?

• It is made up of a single solid plate.

• It is constantly shrinking.

• It is composed of seven major tectonic plates and many smaller ones.

• It is completely stationary.

How do tectonic plates behave on Earth's surface?

• They dissolve over time.

• They float and move like ice on a lake.

• They remain completely still.

• They sink into the ocean.