Basic Concepts
In a nutshell: Geology explores Earth's structure, rocks, and the forces that shape the land.
## Digging Into Geology
Geology is the study of Earth's solid materials—rocks, minerals, and the processes that shape the planet's surface. Geologists uncover stories about Earth's past by examining rock layers, fossils, and natural formations.
### Layers of the Earth
- **Crust**: The thin, outer layer where we live.
- **Mantle**: Thicker, made of hot, flowing rock.
- **Core**: The center, with a liquid outer part and a solid inner part.
### Rock Types
- **Igneous**: Formed from cooled magma or lava.
- **Sedimentary**: Made of particles pressed together over time.
- **Metamorphic**: Changed by heat and pressure.
## Why Geology Matters
Geology helps us find resources like oil, water, and minerals, and understand natural hazards like earthquakes and volcanoes.
Examples
- Discovering fossils in sedimentary rocks.
- Studying volcanoes to predict eruptions.
Key terms
- Igneous Rock
- Rock formed from cooled magma or lava.
- Sedimentary Rock
- Rock made from compressed particles or sediments.
- Metamorphic Rock
- Rock changed by heat and pressure.