Rocks and minerals are classified according to their chemical and physical properties. Rocks also are classified according to how they are formed. Sort and group rocks and minerals into natural classification systems using physical and chemical tests. Sedimentary rocks, which are made of particles from other rocks and organic remains, are laid down in horizontal layers. Fossilized remains and successive layering of sedimentary rocks provide evidence of the Earth's history.
Absolute age is determined by radioactive dating.
Construct models and geological profiles to demonstrate the age relationship of sedimentary rock layers. The atmosphere has properties that can be observed, measured, and used to predict changes in weather and to identify climatic patterns. Compare and contrast the measurements to local and regional weather data. Water falling to Earth flows over the surface as run-off and collects in ocean basins, rivers, lakes, ice caps, and underground. Human activity and natural events can introduce chemicals affecting the quality of the water supply.