Many larger rivers in the Colorado Plateau region meander in deep, narrow canyons and have no floodplains. How could this happen?
A)As sea level rose, the original, old age streams were rejuvenated.
B)Original, old age streams downcut as the land gradually rose.
C)Original, youthful streams continued to downcut as the land rose.
D)As sea level dropped, the original youthful streams matured into old- age streams.

Question

Quizplus · Accepted Answer

As the land gradually rose, the streams downcut into the bedrock, carving deep, narrow canyons and leaving no room for floodplains to form. This process is called "entrenchment." Choice A is incorrect because sea level changes are not relevant to the formation of canyons in this region. Choice C is incorrect because youthful streams are not able to downcut as deeply as older streams. Choice D is incorrect because sea level dropping is not relevant to the formation of canyons in this region.

Many Larger Rivers in the Colorado Plateau Region Meander in Deep