Investigation 2.2

Pima Point
Why do some areas of the Grand Canyon have plants growing and other areas do not?
This is a relevant question because in order for vegetation to grow, certain conditions must exist. Vegetation might indicate where water once was or something about the rock and soil composition.

Where is the best location to camp in the Grand Canyon?
This is not a relevant question because it does not get at the origin, structure, age, or composition of the Grand Canyon.

There appears to be lines on the cliff walls of the Grand Canyon. What causes these lines?
This is a relevant question because the color and width of these lines can indicate many things about the geologic history of the canyon. The lines could indicate relative time periods when certain parts of the canyon were under water as well as length of time over which deposition and sedimentation occurred.

Photo Exhibit
In the picture, there is a vertical cliff wall with light colored layers of rocks. There is a sloping pile of darker colored rock and plant material below the cliff.
This is a relevant question because of conditions necessary for plant growth. The color of the rocks could indicate different composition or different conditions present during formation.

Rock climbers would not like to climb this cliff because the rock is too hard.
This could be a relevant question. If the focus is on the hardness of the rock and its composition, then it would be. If the focus is on the rock climber, then it would not be relevant.

This would make a good place to stop and have a picnic as you raft down the river.
This is not a relevant question because it does not get at the origin, structure, age, or composition of the Grand Canyon.

Rock Samples
The rock is pretty.
This is not a relevant observation. It is simply an opinion.

The rock is gray.
This is a relevant observation. Rock color can shed light on a rock’s geologic past.

The rock is smooth. This is a relevant observation. The texture of a rock can shed light on how a rock was formed.