Complete question:
Geologists are conducting a study on many layers of different types of rock in the Grand Canyon. These geologists will likely find ancient fossils that reveal the history of life near the Grand Canyon in
- igneous rock layers
-
layers of sedimentary rock
-
layers of volcanic rock.
-
metamorphic rock layers
Answer:
layers of sedimentary rock
Explanation:
Most rocks in the Grand Canyon are sedimentary rocks, formed while <em>sediments of sand and mud got deposited in thick layers and got compacted through the pass of time until becoming a rock</em>. Sedimentary rocks have been chronologically accumulating for years, reflecting the geological formation known as superposition. According to this sedimentary deposition, we can distinguish the older rocks located in the deepest areas from the younger rocks in more superficial layers.
As the sedimentary layers were deposited chronologically, they reflect the canyon history by keeping in each layer some of the forms of life that used to inhabit this area in the past. Such is the example of the superficial limestone stratum where many marine animal fossils are found, like clams, fish, and corals.
