Examine Record A. Use the three basic rules to figure out the ages of the layers. In Chart A, list the layers from youngest to oldest with the youngest layer in the first row. Look for signs of tilting, erosion, or folding. In the second column in Chart A, write whether you think tilting, erosion, or folding took place. Write tilting, erosion, or folding next to the letter of any rock layer that was formed when the tilting, erosion, or folding took place. If you see no evidence of tilting, erosion, or folding, write none.

Repeat steps 1 and 2 for Record B. Record the data in Chart B.
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Ageologist is working in an area with exposed sedimentary rocks and finds a well exposed sequence of stratified rocks. as he works through a thick sequence of limestone, he sees abundant large clam fossils that produce an interlocking texture suggesting a reef, but within the limestone section these clams disappear and the overlying limestone is made up primarily of fragments of corals. he now moves 50 km away and finds limestones interbedded with shales, and the limestones contain the same clam fossils he had seen previously 50 km away. as he continues through this section, the rocks become entirely limestone, and the clams disappear again with coral fossils above forming a reef structure. he concludes