Lecture 02-13-2017

Question 1

What are dune sand stones best for?

Answer 1

aquifers

Question 2

How to minimize damage from wind action for dunes and other geological features prone to erosional forces?

Answer 2

1. Grasses with extensive root systems
2. Windbreaks
3. Shelter-belts
4. Terracing
5. Contour ploughing of slopes

Question 3

Where are most of the Dunes in Canada? Provide an example.

Answer 3

Between Alberta and Saskatchewan on the Precambrian Shield, most northerly active sand dunes (e.g., Althabascan Sand Dunes, Alberta, also home to super old sand stones).

Question 4

Cross bedding

Answer 4

Two patterns etched onto one surface which illustrate the path of different directional erosional forces.

Question 5

Mass movement

Answer 5

1. Movements of earth bodies (e.g., soil, bedrock, rock debris, soil, or mud, etc.)
2. Due to the pull of gravity
3. Typ. on hill slopes (e.g., landslides, mud slides, and avalanches.).

Question 6

Dynamic Equilibrium

Answer 6

The changing and ongoing balance of erosion and deposition.

Question 7

What are the 5 different types of streams?

Answer 7

1. Alluvial fan (e.g., Death Valley, Cali.)
2. Braided stream (e.g., Kicking Horse Riv.)
3. Sinuous and Meandering streams (e.g., Opeongo Riv.)
4. Deltas (e.g., St. Clair Riv. Delta)
5. Ox-bow lakes

Question 8

Alluvial fan

Answer 8

Alluvium (e.g., gravel, sand and silt) deposited across an expanding triangular plane flowing from precedingly higher elevations.

Question 9

Braided stream

Answer 9

Longitudinal bars (deposits) of sorted material in rivers with high sediment loads (e.g.,Kicking Horse Riv.).

Question 10

What are two prominent geomorphological features of Sinuous and Meandering streams like the Opeongo River?

Answer 10

1. Pool - erosion on outer part of the meander
2. Point bar - deposition on the inner part of the meander

*Both due to the helical flow of water through meanders

Question 11

Deltas

Answer 11

Landforms of deposited sediment carried by rivers which dump their sediment load as they collide with slower-moving or standing water (e.g., St. Clair River Delta).

Question 12

Ox-bow lakes

Answer 12

A lake formed when a meandering loop gets cut out from the main channel of a flowing river resulting in the creation of an ox-box.

Question 13

Row Crop

Answer 13

Bands of crops at right angles to the slope direction.

Question 14

Hoodoo

Answer 14

Erosional forces which remove the strata of a column of earth material at different rates resulting in a wavy looking column that resembles a silhouette of a vase (e.g., Writing on the Stone Provincial Park, Alberta)

Question 15

When do the most dramatic changes occur to River Banks and the bars and islands of braided streams?

Answer 15

When floods occur.

Question 16

A floodplain can be around __x the original width of a steam.

Answer 16

18

Question 17

What effect does urbanization have on surface infiltration?

Answer 17

Reduces surface infiltration.