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Why are fossils of organism's from the phanerozoic eon much more likely to be found than fossils of organisms from any other eon? a. more organisms present during the phanerozoic eon had soft body parts. b. organisms present during the phanerozoic eon were all microscopic. c. more organisms present during the phanerozoic eon had hard body parts. d. organisms present during the phanerozoic eon are the most ancient life forms.

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

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