The Solid Earth - Chapter 3: Stages of Valley Development

Question 1

Who proposed that streams were responsible for cutting the valleys in which they flowed?

Answer 1

James Hutton

Question 2

The three sequential stages into which the evolution of a valley has been divided

Answer 2

youth, maturity, old age

Question 3

The valley is considered ____ when the stream is downcutting to establish a graded condition with its base level

Answer 3

youthful

Question 4

5 Other features of youth in a valley

Answer 4

steep gradient
little or no floodplain
rapids
occasional waterfall
relatively straight course

Question 5

When a stream reaches maturity, downward erosion diminishes and ____ ____ dominates

Answer 5

lateral erosion

Question 6

The mature stream begins to create a _________

Answer 6

floodplain

Question 7

In which stage do cutoffs occur?

Answer 7

Mature

Question 8

A stream enters old age after it is has cut its floodplain several times wider than its ____ ____, or width of meander

Answer 8

meander belt

Question 9

During the transition from youth to old age, the land is uplifted or the ___ ____ is lowered

Answer 9

base level

Question 10

Uplifting of a mature stream would cause it to abandon lateral erosion and revert to ______

Answer 10

downcutting

Question 11

Rivers that ae taken from lateral erosion to downcutting (mature to young)

Answer 11

rejuvenated

Question 12

Meanders of a rejuvenated stream

Answer 12

entrenched

Question 13

When streams eventually readjust to uplift by cutting a new floodplain at a level below the old one, the remnants of high floodplain are called ___

Answer 13

terraces