Question

In western Utah, there are large rock formations comprised of layers of sedimentary rock limestone. Which of the following is the most likely explanation?

A. Western Utah used to be under water (an ocean or inland sea).
B. Western Utah used to have many active volcanoes.
C. The rocks in western Utah used to be buried many miles beneath the Earth’s surface.
D. The rocks in western Utah have been subjected to extreme temperatures and pressures.
E. The rock cooled quickly as it formed on the surface.

Answer 1

Hey there! I'm happy to help!

Much of Utah used to be covered by a prehistoric body of water called Lake Bonneville. Evidences of this include fossils of trilobites and fish in Utah's mountains.

Sedimentary rocks are comprised of sediments (small bits and pieces of weathered rock), and the reason sedimentary rock formations are usually layered is because they were formed underwater. The pressure of the water compacts the rocks, and as new sediments arrive in the water, it is compacted on top of the previous compressed rock, creating layers.

Since we know that much of Utah used to be a lake, the best explanation for this sedimentary rock limestone is that A. Western Utah used to be under water (an ocean or inland sea).

Have a wonderful day and keep on learning! :D