Tectonic Plates Quiz Regrade

1. Islands can form from magma which is pushed up at a convergent plate boundary

This is correct because, in subduction zones, the oceanic crust is pushed downwards, causing the magma to form islands.

2. Which boundary type adds to the lithosphere? (the hard outer crust of the Earth)

The correct answer is divergent boundaries. In divergent boundaries, the plates move apart from each other, so the magma underneath fills in the gap and adds to the lithosphere.

6. The theory that says Earth's continents once made up an ancient supercontinent and have been drifting apart ever since is called the theory of Plate Tectonics.

The correct answer is Plate Tectonics because "tectonics" means a long process that may affect the Earth's crust. This means that 'plate tectonics' is the theory that the Earth's continents have been drifting apart.

18. A fault is formed by the movement of a transform plate boundary

The correct answer is transform boundary. This is the correct answer because the movement of transform boundaries (side to side) create spaces, which are considered faults.

20. Most geologists rejected Alfred Wegener's idea of Continental Drift because Wegner could not identify the force that moved the continents.

This makes sense because, at the time that Wegener was doing research of the Continental Drift, there was no proof that there was a thing such as tectonic plates, so people did not believe him.

21. Which of the following is NOT evidence to support the theory of plate tectonics?

The correct answer is sand erosion. I know this is a correct answer because fossils, glaciers, and mountains are all effects of tectonic plate movements.

22. Oceanic Trenches are formed by Divergent plate boundaries

I know that this is the correct answer because when plates pull apart from each other, magma forms new crust. However, since divergent boundaries happen mostly underwater, they create oceanic trenches.

26. This theory states that Earths plates move on top of the mantle at a slow and constant rate due to convection currents.

The correct answer is plate tectonics. I know that this is correct because "tectonics" means a long process that may affect the Earth's crust. This means that 'plate tectonics' is the theory that the Earth's plates are moving very slowly over a long process and time.