Across
- 3. The concept that the processes that have shaped Earth in the geologic past are essentially the same as those operating today.
- 8. A tentative explanation that is then tested to determine if it is valid.
- 10. A major division of geology that examines the materials of Earth and seeks to understand the processes and forces acting beneath and upon Earth’s surface.
- 15. The solid Earth; one of Earth’s four basic spheres.
- 17. Rock formed from the weathered products of preexisting rocks that have been transported, deposited, and lithified.
- 18. The rigid outer layer of Earth, including the crust and upper mantle.
- 19. The part of the mantle that extends from the core–mantle boundary to a depth of 660 kilometers (410 miles). Also known as the Mesosphere
- 21. The totality of life-forms on Earth.
- 22. Rock formed by the alteration of preexisting rock deep within Earth (but still in the solid state) by heat, pressure, and/or chemically active fluids.
- 24. The science that examines Earth, its form and composition, and the changes that it has undergone and is undergoing.
- 25. The innermost layer of Earth. It is thought to be largely an iron–nickel alloy, with minor amounts of oxygen, silicon, and sulfur.
Down
- 1. The concept that Earth was shaped by catastrophic events of a short-term nature.
- 2. The gaseous portion of a planet, the planet’s envelope of air. One of the traditional subdivisions of Earth’s physical environment.
- 4. The lowest portion of the upper mantle.
- 5. A major division of geology that deals with the origin of Earth and its development through time. Usually involves the study of fossils and their sequence in rock beds.
- 6. The water portion of our planet; one of the traditional subdivisions of Earth’s physical environment.
- 7. A model that illustrates the origin of the three basic rock types and the interrelatedness of Earth materials and processes.
- 9. An interdisciplinary study that seeks to examine Earth as a system composed of numerous interacting parts or subsystems.
- 11. A group of interacting or interdependent parts that form a complex whole.
- 12. Unconsolidated particles created by the weathering and erosion of rock by chemical precipitation from solution in water, or from the secretions of organisms, and transported by water, wind, or glaciers.
- 13. Rock formed from the crystallization of magma.
- 14. One of Earth’s compositional layers. The solid rocky shell that extends from the base of the crust to a depth of 2900 kilometers (1800 miles).
- 16. A subdivision of the mantle situated below the lithosphere. This zone of weak material exists below a depth of about 100 kilometers (60 miles) and in some regions extends as deep as 700 kilometers (430 miles). The rock within this zone is easily deformed.
- 20. A well-tested and widely accepted view that explains certain observable facts.
- 23. The very thin, outermost layer of Earth.