Landslides change the surface of the Earth. They happen when rocks, soil, and anything else on the ground falls down a slope after becoming too weak or unstable to resist gravity. A slope includes mountains, hills, and cliffs. They happen on every continent on Earth, but they are most common in … [Read more...] about What are Landslides?
Earth Science
Learning About How Volcanoes Form
Volcanoes are mountains formed around vents or fissures in the Earth's crust that release lava, ash, rock, and gases. When volcanoes erupt, they release heat from the Earth's interior. The Earth's core contains decaying radioactive elements that release heat when they break down. This heat drives … [Read more...] about Learning About How Volcanoes Form
Learning About Pangaea the Supercontinent
For most of human history, people believed that the continents didn't move. However, as technology improved, scientists could see the ways the land on Earth was constantly changing. This led to the discovery of Pangaea the supercontinent. Millions of years ago, all of the land on Earth joined … [Read more...] about Learning About Pangaea the Supercontinent
How did Scientists Discover Seafloor Spreading?
Seafloor spreading happens at divergent plate boundaries under the ocean. As hot rocks rise in convection currents within the asthenosphere, they push the tectonic plates above them apart. The top of the convection current heats the crust above it and melts some of the rock, so it becomes magma. As … [Read more...] about How did Scientists Discover Seafloor Spreading?
Everything You Need to Know About Minerals
What are Minerals? Minerals are naturally occurring, inorganic, solids with definite chemical compositions and ordered internal structures. Naturally occurring means that they form in nature. People do not create them. For example, steel is not a mineral, but gold is. Inorganic means they are … [Read more...] about Everything You Need to Know About Minerals
What is the Evidence for the Theory of Plate Tectonics?
The theory of plate tectonics is new, but some of the evidence for the theory of plate tectonics dates back millions if not billions of years. In the 1960s, geologists installed seismometers to monitor nuclear testing in the United States. The seismometers also recorded geologic activity, including … [Read more...] about What is the Evidence for the Theory of Plate Tectonics?