Page 208 - Laboratory Manual in Physical Geology

A CTIVIT Y 6.7 Grand Canyon Outcrop Analysis and Interpretation

Name: ______________________________________ Course/Section: ______________________ Date: ___________

A. Analyze the images above, from the South Rim of the Grand Canyon, near Grand Canyon Village. The edge of the canyon here is
made of a Permian calcarenite (sand–sized fossilifereous limestone) called the Kiabab Limestone. It is about 270 million years old.
Brachiopod shells

Horn
Crinoid stems coral
(related to starfish)

1. Notice that some of the beds in the outcrop are cross-bedded. Draw an arrow on the picture to show the direction that the

water moved here to make this cross bedding. Refer to FIGURE 6.12 as needed.

2. Which kind of cross bedding is this? ( FIGURE 6.12 )? _________________________________________
3. REFLECT & DISCUSS Describe (as well as you can) what the environment was like here about 270 million years ago
and the evidence and logic that you used to reach your conclusion.

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