Across
- 1. a nonrenewable energy used in nuclear power plants that is not a fossil fuel
- 4. a process where high-pressure water splits apart undergound rocks, releasing trapped natural gas
- 5. a fossil fuel found underground that is mostly made up of methane
- 7. oil; a liquid fossil fuel found in underground rock formations
Down
- 2. a type of coal mining used when the coal is located deep below the Earth's surface
- 3. a process where the inner core of an atom is split and energy is released
- 6. a type of coal mining used when the coal is located near the Earth's surface