Gesc 102 Midterm 2

Front 1

Geomorphology

Back 1

The study of landforms, processes, thresholds, and budgets, that shape landscapes

Front 2

Coarse scales

Back 2

An observation scale in which it's possible to classify regions according to a range of criteria

Front 3

Fine scales

Back 3

An observation scale that closely examines details to learn about specfic processes

Front 4

Driving force

Back 4

The application of energy to Earth materials & its surface

Front 5

Endogenic forces

Back 5

Forces that are a result of internal energy like the movement of plate techtonics

Front 6

Exogenic forces

Back 6

Forces that are a result of external energy such as solar

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Process

Back 7

An action that's involved when a force induces change in Earth’s materials or a landscape

Front 8

Basic equilibrium concept of gk gilbert

Back 8

landscapes remain at equilibrium if the driving forces & resistances to those forces remain unchanged

Front 9

Resisting Frameworks

Back 9

control how the landscape responds to the driving forces

Front 10

static equilibrium

Back 10

Equilibrium where landscapes do not change form.

Front 11

steady state equilibrium

Back 11

Equilibirum where landscapes change around some average form.

Front 12

dynamic equilibrium

Back 12

Equilibrium where the average form of a landscape is progressively changing.

Front 13

Metastable equilibrium

Back 13

equilibrium that's punctuated by major change

Front 14

Soil

Back 14

An unconsolidated layer of weathered rock at interface of lithosphere, biosphere, & atmosphere. It is a mobile layer (involved in erosive processes).

Front 15

Saprolite

Back 15

Disintegrated rock that is in its original location (not transported), retains some structure & remains in place. It's chemically & physically weathered.

Front 16

Bedrock

Back 16

Unweathered parent material

Front 17

Hydrolysis

Back 17

A chemical reaction between silicates and an aqueous solution containing free H+ (acidic solution).

Front 18

Eluviation

Back 18

the transportation of dissolved or suspended material within the soil by the movement of water when rainfall exceeds evaporation.

Front 19

Illuviation

Back 19

The accumulation of dissolved or suspended soil materials in one area or horizon as a result of eluviation from another.

Front 20

Soil horizons

Back 20

O, A, E, B, C, R

Front 21

O horizon

Back 21

Contains loose and partly decayed organic matter

Front 22

A horizon

Back 22

Contains mineral matter mixed with some hummus

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E horizon

Back 23

Contains the zone of eluviation and leaching

Front 24

B horizon

Back 24

Contains the accumulation of clay, iron, and aluminum from above

Front 25

C horizon

Back 25

Contains partially altered parent material

Front 26

R horizon

Back 26

Contains untethered parent material

Front 27

Aridisol

Back 27

A soil that has no O horizon, no leaching, and has high solubility materials in its B horizon

Front 28

Alifisol

Back 28

A soil that has distinct o, a, e, b, and c layers, an organic rich O horizon, a moderately leached E horizon, and has a B horizon with insoluble materials

Front 29

Oxisol

Back 29

A soil that has no O horizon, a heavily leached E horizon, and has a B horizon with only insoluble materials

Front 30

Laterite

Back 30

A reddish oxide and clay-rich material (hard when dry) that forms a topsoil in some tropical/subtropical regions.

Front 31

Transport limited hillslope traits

Back 31

• Sediment (soils) delivered from hillslope to valley is limited by rate soil & rock can be transported • Sediment supply > capacity to carry sediment • Temperate/Humid climates = transport limited • Weak bedrock in most climates • Long exposure times with limited soil transport

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Weathering limited hillslope traits

Back 32

• Sediment delivered from hillslope to valleylimited by rate of sediment production • Sediment supply < capacity tocarry sediment • Arid climates = weathering limited • Strong bedrock, possible even intemperate climates • New bedrock exposures may be weathering limited to start • Tectonics, glacial processes, mass wasting may reveal bedrock

Front 33

Positive hillslope curvature

Back 33

A curvature where slopes increase from the summit of the hill

Front 34

Negative hillslope curvature

Back 34

A curvature where slopes decrease from the summit of the hill

Front 35

Hillslope evolution

Back 35

1. Begins with freshly exposed bedrock cliff or mountain

2. Soil develops and the hill becomes parabolic

3. Soil develops more and is transported from the summit to the valley

4. Hill backwastes and leaves a thin divide & a predominately concave up slope morphology

Front 36

Diffusive soil transport

Back 36

Transport that's slow and gravity driven across the entire slope

Front 37

Advective soil transport

Back 37

Transport that's more rapid and channelized

Front 38

Creep

Back 38

The slow, gravity driven downslope movement of loose soils

Front 39

Steady diffusion

Back 39

Diffusion where change does not vary with time

Front 40

Uniform diffusion

Back 40

Diffusion where change is equal everywhere

Front 41

Shear stress

Back 41

The horizontal component of the stress/force exerted by flow on the bed

Front 42

Shear stress equation

Back 42

tb = pghs

P is water density

H is flow thickness

S is surfacd slope

Front 43

Shear strength

Back 43

The relationship between shear force and normal force in a block of material on a slope.

Front 44

Factor of safety equation

Back 44

Factor of safety = resisting stress/driving stress

fs>1 = stable slope

fs<1 = unstable slope

Front 45

Debris flow

Back 45

The relatively rapid mass movement of loose material on a hillslope (soils and other non-lithified granular materials), can be dry or wet.

Front 46

Hummocky

Back 46

Jumbled debris at leading edge of slide. Internal structure of hill not maintained here

Front 47

Erosion

Back 47

The removal of material from the surface of a landscape

Front 48

Erosion rate

Back 48

The rate at which material is removed from a landscape. Rates are lowest in arid climates, with humid climates having the highest

Front 49

Rock uplift

Back 49

The displacement of rocks relative to sea level

Front 50

Surface uplift

Back 50

The net uplift when erosion is also accounted for

Front 51

Sediment yield

Back 51

The amount of sediment leaving a watershed

Front 52

Adiabatic cooling

Back 52

the process of reducing heat through a change in air pressure caused by volume expansion.

Front 53

Orographic effect

Back 53

A change in atmospheric conditions caused by a change in elevation, primarily due to mountains.

Front 54

Horton overland flow

Back 54

A flow of water where there's a tendency of water to flow horizontally across land surfaces when rainfall has exceeded infiltration capacity and depression storage capacity

Front 55

Saturation overland flow

Back 55

A water flow that occurs when the combination of precipitation intensity and duration (and run-on from higher areas) saturates the soil and raises the water table to the surface

Front 56

Ephemeral stream

Back 56

a stream that flows only briefly during and following a period of rainfall in the immediate locality.

Front 57

Perennial stream

Back 57

a stream or river (channel) that has continuous flow in parts of its stream bed all year round during years of normal rainfall.

Front 58

Drainage density

Back 58

The measure of the total length of channels over a given area.

Front 59

Drainage density equation

Back 59

dd=l/a

L is the sum of the channel length in a watershed

A is the area of the watershed

Front 60

Supply limited slopes

Back 60

Slopes where sediment transport in a stream is limited by the supply of sediment delivered from a watershed

Front 61

Transport limited slopes

Back 61

Slopes where sediment transport is limited only by the hydraulic capacity to carry sediment

Front 62

Knickpoint

Back 62

The part of a river or channel where there is a sharp change in channel slope, such as a waterfall or lake.

Front 63

Cavitation

Back 63

the rapid formation and collapse of vapor pockets in a flowing liquid in regions of very low pressure, a frequent cause of structural damage to propellers, pumps, etc.

Front 64

Alluvial fan

Back 64

A fan-shaped mass of alluvium deposited by water flow at a slope break.

Front 65

Froude Number

Back 65

a dimensionless number that defines different flow regimes in a flow (subcritical, supercritical). If the number is above 1, it's supercritical. If the number is lower than 1, it's subcrtical

Front 66

Bernoulli Effect

Back 66

The pressure differential around an object generates a lift force

Front 67

Bedform

Back 67

A feature that develops at interface of fluid and a moveable bed, result of bed material being moved by fluid flow

Front 68

Sinuosity

Back 68

A term that's used to define the degree of meandering of a riverbed, which is then used to establish geomorphological river types.

Front 69

Sinuosity Equation

Back 69

Sinuosity = length of steam channel/length of straight line distance

Front 70

Thalweg

Back 70

The line connecting the fastest flow in a channel

Front 71

Helical flow

Back 71

A rotational flow that is the result of a river responding to changes in direction. Superelevation around outer bend (cut bank) of a river generates a pressure gradient which drives helical flow.

Front 72

Types of channel patterns

Back 72

•Straight (highlands & pediment)

•Braided (alluvial fans & plains)

•Meandering (plains)

•Anastomosing (coastal plains)

Front 73

Submergent Coastline

Back 73

A coastline where the relative rate of sediment input is less than relative rate of sea level rise (transgression).

Front 74

Prograding Coastline

Back 74

A coastline where the relative rate of sediment input outpaces changes to sea level

Front 75

Emergent Coastline

Back 75

A coastline where there's exposure of the coastline due to relative sea level fall