Page 333 - Laboratory Manual in Physical Geology

3. Observe the profile that you constructed in part D2. 3000

Label the part of the profile that is “bedrock eroded
by Cedar Creek” and the part that is “sediment
deposited from Cedar Creek.” 2000
4. Observe Cedar Creek on the map in part D2.

a. What is its stream order classification at point L?
1000
900
800

b. What happens to that stream’s gradient and order 700
downstream, as it enters the alluvial fan, and how 600
does this contribute to the formation of the alluvial
fan? 500
400
300

E. On the semi-logarithmic graph paper provided at right,

you can determine if a stream is linear, sinuous, or 200
meandering by plotting a point based on the stream’s
gradient and sinuosity. Linear Sinuous Meandering
1. Plot points for the following streams, and draw a best-

fit line through the points: 100
90
■ Stream segment A-B (Garvin Canyon stream) 80

from part B4 of this activity 70 Gradient in feet per mile
60
■ Stream segment C-D (Timber Canyon stream)

from part B5 of this activity 50

■ Stream segment E-F (tributary of Passage Creek) 40
from part C2
30

■ Stream segment G-H (Passage Creek) from
part C3

2. Based on the summary graph that you just completed, 20
is there a relationship between a stream’s gradient
and whether its channel is straight, sinuous, or
meandering? If yes, then what is that relationship?
10
9
8
7
6
5
F. REFLECT & DISCUSS Compare the four landscapes
that you studied in this activity. What factors determine 4
the kind of drainage pattern that develops on a landscape
and whether a stream is eroding bedrock or depositing 3
sediment?
2

0
1.0 1.3 1.5 2.0 3.0 4.0
Sinuosity

303