Page 209 - Laboratory Manual in Physical Geology

A CTIVIT Y 6.8 Using the Present to Imagine the Past—Dogs and
Dinosaurs

Name: ______________________________________ Course/Section: ______________________ Date: ___________
A. Analyze photographs X and Y below.

X. Modern dog tracks in mud with mudcracks on a tidal flat, Y. Triassic rock (about 215 m.y. old) from southeast
St Catherines Island, Georgia (x1) Pennsylvania with the track of a three-toed Coelophysis
dinosaur (x1)

1. How are the modern environment (Photograph X) and Triassic rock (Photograph Y) the same?

2. How are the modern environment (Photograph X) and Triassic rock (Photograph Y) different?

3. Describe what the Pennsylvania ecosystem (environment + organisms) was like when Coelophysis walked there about
215 million years ago.

B. REFLECT & DISCUSS Use what you learned about sediment and sedimentary rocks. Develop a hypothesis about how the
dinosaur footprint in Photograph Y was preserved.

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