Chapter 12

Question 1

What is the functional role of a slope?

Answer 1

one of throughput: 1) evacuation of rock and debris
prepared by weathering and 2) of water carrying elements in solution
and suspension.

Question 2

What is throughflow?

Answer 2

the lateral unsaturated flow of water in the soil zone, typically through a highly permeable geologic unit overlying a less permeable one. Water thus returns to the surface, as return flow, before or on entering a stream or groundwater.[1][2] Once water infiltrates into the soil, it is still affected by gravity and infiltrates to the water table or if permeability varies laterally travels downslope.[1] Throughflow usually occurs during peak hydrologic events (such as high precipitation). Flow rates are dependent on the hydraulic conductivity of the geologic medium

Question 3

Where do slopes come from?

Answer 3

• Orogenic activity
• Linear erosion (e.g., Grand Canyon – 0.25 mm a−1 for 8Ma)
• Marine action
  Slope form arises gradually

Question 4

What is orogenic activity? (orogeny)

Answer 4

mountain-building process that takes place at a convergent plate margin when plate motion compresses the margin.

Question 5

How is water transferred?

Answer 5

• Potential energy (ability to do work) of the water: water potential moves
  along a gradient from high to low potential
• Infiltration – movement of water into the soil (infiltration capacity)
• Three vertical moisture zones arise:
• wetting zone
• transmission zone
• saturated zone

Question 6

Water potential moves along a gradient from __ to ___

Answer 6

high to low potential

Question 7

What are the three vertical moisture zones?

Answer 7

wetting zone, transmission zone, saturated zone

Question 8

Wetting zone

Answer 8

In this zone, the water content sharply decreases with depth from the water content of the transmission zone to near the initial water content of the soil.

Question 9

Transmission zone

Answer 9

This zone is characterized by a small change in water content with depth. In general, the transmission zone is a lengthening unsaturated zone with uniform water content. The hydraulic gradient in this zone is primarily driven by gravitational forces.

Question 10

saturated zone

Answer 10

The pore space in this zone is filled with water or saturated. Depending on the length of time elapsed from the initial application of the water, this zone will generally extend only to a depth of a few millimeters.

Question 11

Darcy’s law

Answer 11

the capability of the liquid to flow via any porous media like a rock
q = K(H/L)
* q= discharge
* H/L = hydraulic gradient
(height/length)
* K = hydraulic conductivity
how much water is discharged as it goes through the soil matrix

Question 12

what is the hydrological cycle?

Answer 12

movement of water into the soil and down through soil layers to the capillary zone etc

Question 13

The larger the particle size ___ the more __

Answer 13

-larger the particle size= the more permeable; ease of water to permeate the ground; larger particles = bigger gaps vs smaller particles that have smaller gaps

Question 14

soils are layered into horizons of __

Answer 14

different conductivities

Question 15

Non-capillary macropores permit __

Answer 15

rapid
movement of water (karst, soil fauna, growth
and decay of roots, natural pipe network

Question 16

Overland flow occurs when

Answer 16

rate of
precipitation exceeds infiltration capacity

Question 17

Saturated overland flow

Answer 17

rare except in case
of impervious surfaces
-can occur due to surface water input on areas that are already saturated with water

Question 18

How are minerals transferred?

Answer 18

-Mass movement – slide, flow and heave
* Particulate movement – can change position relative to neighbors, fall, rainsplash,
surface wash
* Movement in solution – slope water comes in contact with rock and ion minerals;
controlled by
* solubility of the minerals,
* degree of under saturation of the water, and
* length of time the water remains in contact with the slope minerals.

Question 19

Mass movement of minerals

Answer 19

-weather limited slopes: bedrock
-transport-limited slopes: lowland topography with limited relief (there’s no more energy there to transport it)

Question 20

Maryland consists of:

Answer 20

Atlantic Coastal Plain, Piedmont, and Blue Ridge (edge of the Appalachians)
-grenville orogeny (cycles of uplift and erosion)
-Appalachians are older mountains that occurred from tectonic plate collision leaving erosion-resistant rock