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AAS.SC15.6.8 Identify the physical process (sedimentation, heat and pressure, weathering, cooling) that results in the formation of rocks; use a model to demonstrate the rock cycle.

Unpacked Content

Scientific and Engineering Practices

Planning and Carrying out Investigations

Crosscutting Concepts

Energy and Matter


Students know:
  • Rocks are the solid mineral materials forming part of the surface of the Earth and other similar planets.
  • Different Earth processes (melting, sedimentation, crystallization) drive matter cycling (from one type of Earth material to another) through observable chemical and physical changes.
  • Chemical changes are changes that result in the formation of new chemical substances.
  • Physical changes involve changes into new forms or shapes in which the chemical identity of the substance is not changed.
  • Melting is a physical change in which a solid changes to a liquid as a result of exposure to heat.
  • Sedimentation is a process in which material (like rock or sand) is carried to the bottom of a body of water and forms a solid layer. Sedimentary rock consists of cemented sediment.
  • Crystallization is the process of the formation of crystals from a liquid. Igneous rocks are the result of crystallizing magma.
  • Deformation is a physical change in a rock's shape or size. Rocks become deformed when the Earth's crust is stretched, compressed, or heated.
  • Metamorphic rock was once one form of rock but changed to another under the influence of heat or pressure.
  • Energy from Earth's interior and the sun drive Earth processes that together cause matter cycling through different forms of Earth materials.
  • The movement of energy that originates from the Earth's hot interior causes the cycling of matter through the Earth processes of melting, crystallization, and deformation.
  • Energy from the sun causes matter to cycle via processes that produce weathering, erosion, and sedimentation (e.g., wind, rain).
  • Weathering is the chemical or physical breaking down or dissolving of rocks and minerals on Earth's surface.
  • Erosion is the act in which Earth is worn away, often by wind, water, or ice.


Students are able to:
  • Identify the phenomena under investigation, which includes the chemical and physical processes of Earth.
  • Identify the purpose of the investigation, which includes demonstrating the chemical and physical processes that form rocks and cycle Earth materials.
  • Develop a plan for the investigation individually or collaboratively.
  • Describe factors used in the investigation including appropriate units (if necessary), independent and dependent variables, controls and number of trials for each experimental condition.
  • Perform the investigation as prescribed by the plan.
  • Use data from the investigation to provide an causal account of the relationship between chemical and physical processes and the formation of rocks and the cycling of Earth materials.


Students understand that:
  • All Earth processes are the result of energy flowing and matter cycling within and among the planet's systems. This energy is derived from the sun and Earth's hot interior. The energy that flows and matter that cycles produce chemical and physical changes in Earth's materials.


  • Rock
  • Melting
  • Sedimentation
  • Crystallization
  • Chemical change
  • Physical change
  • Deformation
  • Interior energy
  • Cycling
  • Weathering
  • Erosion
  • Solar energy
  • Sedimentary rock
  • Igneous rock
  • Metamorphic rock