Front

What are index fossils?

Back

Index fossils are fossils of organisms that were widespread but only existed for a short period of geological time. They are used by geologists to date and correlate the age of rock layers.

Front

Why are index fossils useful to geologists?

Back

They tell the ages of many different rock layers.

Front

What is the role of sunlight in forming lake-effect snow?

Back

The sun heats the air and water unequally, generating winds that pick up moisture from the lakes and drop it to the east.

Front

What is the Theory of Plate Tectonics?

Back

The geological theory that states that pieces of Earth’s lithosphere are in constant, slow motion.

Front

How are mountains formed at converging continental plates?

Back

Mountains are formed when two continental plates collide, causing the land to buckle and fold.

Front

What is ocean crust?

Back

Ocean crust is the part of Earth's crust that underlies the ocean basins, typically younger and denser than continental crust.

Front

What evidence supports the Theory of Plate Tectonics?

Back

The age of ocean crust shows that new ocean crust is formed at mid-ocean ridges, pushing older crust away.

Front

What is subduction?

Back

Subduction is the process where one tectonic plate moves under another and sinks into the mantle.

Front

What happens at divergent boundaries?

Back

At divergent boundaries, tectonic plates move apart, leading to the formation of new crust as magma rises to the surface.

Front

What is continental drift?

Back

Continental drift is the theory that continents have moved over geological time and were once joined together.