March 4, 2015

Agenda

1. Roll

2. PowerPoint titled: Wind Erosion and Deposition

3. Possible Video

Questions1. Why are areas with fine materials more likely

to be effected by wind erosion?

2. How does wind move sand and finer materials?

3. What are the effects of wind erosion?

4. What is the difference between dunes and loess?

Subject Area: Wind Erosion and Deposition

EQ: How are the surface features of the Earth changed by wind erosion?

January 30, 2014

Wind Erosion and Deposition

Have you ever been frustrated because the wind blew some very important papers all over the place? Then you go to pick them up and they are on the move again.

Wind Erosion and DepositionAreas where there are little plants and fine

loose material are more vulnerable to wind erosion.

Why do areas with no plants have more erosion from wind?Response: Areas with no plants have more wind erosion because …

Which climates or areas would be shaped moreby wind erosion?Response: The areas shaped more by wind erosion are …

Process of Wind ErosionWind moves material in different ways.

Three ways wind moves material is saltation, deflation, and abrasion.

SaltationIn areas where strong winds occur, material

is moved by saltation. Saltation is the movement of sand-sized particles by a skipping and bouncing action in the direction the wind is blowing.

What is the process of saltation?Response: The process of saltation is …

DeflationDeflation is the lifting and removal of fine

sediment by the wind. During deflation, wind removes the top layer of sediment leaving behind rock particles that are too heavy for the wind to lift them. The hard rocky surface left behind after deflation is called desert pavement.

Deflation Hollows If you have ever blown in a dust pile you will

notice that a small depression will form. Where there is little vegetation the wind may scoop out depressions in the sand known as deflation hollows.

Why do deflation hollows form in areas where there is little vegetation?Response: Deflation hollows form in areas where there is little vegetation because …

AbrasionAbrasion is the grinding and wearing down

of rock surfaces by other rock or sand particles. This commonly occurs in areas where there is loose sand and high winds. Rocks that are sandblasted by abrasion become very smooth and are called ventifacts.

Wind-deposited MaterialMaterial that is picked up by the wind is

eventually deposited somewhere downwind. As wind speed slows heavier materials are deposited first.

DunesAs the material collects it will cause mounds

of material to be formed. The mounds of wind deposited sand are called dunes. Dunes are common in deserts and along the shores of lakes and oceans.

DunesA dune usually has a gentle slope and a

steeply slope side. The steep side of a dune is called the slip face. As sand moves over the crest, or peak, of a dune it will slide down the slip face, creating a steep slope.

Disappearing DunesThe desert tortoise and other animals use

the dunes for their homes. As dune buggies and other motorized vehicles destroy the dunes the animal have no where to live and die off. Some like the desert tortoise are endangered of becoming extinct. This is why some federal agencies have said that some areas are off-limits for off-road vehicles.

LoessWind can deposit material much finer than

sand. Thick deposits of fine sediment are known as loess. Loess is very fine and feels like talcum powder.

LoessLoess can be moved very large distances.

Loess deposits can easily be prepared for growing crops and are responsible for very successful grain growing areas of the world.

What is the difference of a dune and a loess deposit?Response: The difference between a dune and

a loess deposit is …

Summary

1.Answer the essential question “How are the surface features of the Earth changed by wind erosion?”

2.Your answer needs to be in complete sentences.3.Place your answer at the bottom of the notes we

did today. 4.Make sure you include how wind moves sand

and particles around. 5.Use your notes to get the answers.

Erosion and Weathering1. What did you know?_______________________________________________________________________________________________________________________________________2. What did you learn?_______________________________________________________________________________________________________________________________________3. What do you want to know?_______________________________________________________________________________________________________________________________________

Talking PunishmentToday I have decided to break the rules of Mr. Elsmore’s

classroom and have been granted the opportunity to write this paragraph. Unfortunately, it is possible that I have been granted this opportunity because of the actions of another student and not because of my actions. I will be forever indebted to that particular student or group of students for this wonderful opportunity to have to write instead of watching the video that was planned for today. I will make sure to let that student or students know how I appreciate this opportunity and show my gratitude by asking them to stop the breaking of the rules in Mr. Elsmore’s classroom. If you are the one responsible for this punishment please learn how to be mature enough to follow the five simple rules that Mr. Elsmore created to make this classroom an atmosphere of learning and kindness. If we have any more problems then we will get the wonderful opportunity to write this paragraph again and possibly loose the drawing at the end of the triad. All because I cannot or my fellow student cannot follow the rules. What a shame!!!

America’s Economy: Sorrow and Hope

1. What did you know?_______________________________________________________________________________________________________________________________________2. What did you learn?_______________________________________________________________________________________________________________________________________3. What do you want to know?_______________________________________________________________________________________________________________________________________4. What was removed that caused the dustbowl to happen?

Homework

Chapter 11, Section 2 in the purple workbook. This is found on pages 84 – 86.