ERTH 209 Final Exam (W9-W11)

Mass Wasting

Gravity and Shear Resistance (Inclined Plane)

Shear Strength

Cohesion

Angle of Repose

Slope Stability

Angle of Repose and Slope Stability

Water and Pore Space

Mass Wasting Events

Mass Wasting Events Classification

Creep

Solifluction

Debris Flow

Earthflows

Lahars/Mudflows

Debris

Earth

Mud

Slides

Slumps

Rock Falls

Rock Avalanches

Minimizing Slope Hazard

Mass Wasting Event Prevention

Hydrologic Cycle Steps

1. Evaporation

2. Transpiration

3. Condensation

4. Precipitation

5. Infiltration

6. Runoff

Stream

Floodplains

The low-lying, nearly flat alluvial valley floor that is periodically inundated with flood waters.

Stream Velocity

The distance water travels in a stream over a measured time period.

Slow = <1 km/h

Fast = 5 km/h

Flood = 25 km/h

Channel Shape

The greater the cross-sectional area is compared to the wetted perimeter, the greater the velocity, because less of the water is experiences friction.

Gradient

Vertical Drop

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Horizontal Distance

Channel Roughness

The rougher the channel is, the slower the flow.

S

Thalweg

A line Marking the fastest Moving water in a channel.

Discharge

The total volume of water flowing past a point at a given time.

Q = Depth x Width x Velocity

Stream Erosion

1. Hydraulic Action- Force of water

2. Solution- chemical erosion

3. Abrasion- particle erosion

Hydrologic Force

Solution

Abrasion

Stream Sediments

Bedload

Suspended Load

D

Dissolved Load

Flooding Cause

Floodplain Formation

Natural Levee Formation

Built-up area around a river channel which can hold river flow within a channel. Forms from repeated flooding, which builds up ‘walls’ around the edge of the river.

Discharge and Flooding Events

Increased discharge = Increased energy/erosion/transportation

Flood Recurrence Interval

The average number of years between peak discharge values of a certain size. Helps determine how frequently a stream overflows its banks/floods.

Stream Evolution

Base Level

Ultimate Base Level

Local Base Level

Vertical Erosion

Lateral Erosion

Side-to-side erosion in which channel location migrates with time. Erosion on outside bend, deposition on inside bend.

Groundwater

Zone of Aeration

Zone of Saturation

Water Table

Dry Water Table

Wet Water Table

Unconfined Aquifers

Confined Aquifers

Perched Aquifers

Porosity

High Porosity Rocks

Permeability

High Permeability Rocks

Low Permeability Rocks

Aquifer

Aquitard

Darcy’s Law

Henry Darcy

Artesian Well

Natural Springs

Drawdown

Depletion

Subsidence

Contamination

Karst Topography

Karst Geographic Features

Cave and Cavern Formation

Chemical Weathering (Karst)

Karst Rocks

Sinkholes

Glaciers

Erosional Landforms

U-Shaped Glacial Troughs

Hanging Valleys

Cirque

Arete

Horn

Depositional Landforms

Ground Moraine

End Moraine

Lateral and Medial Moraines

Drumlins

Kame

Kettle

Esker

Zone of Accumulation

Zone of Ablation