Weathering, Erosion and Deposition7.8B analyze the effect of weathering, erosion and deposition on the environment in Ecoregions of Texas

Once a rock is formed, does it stay in the same place forever?

Video!

• Crash Course on Weathering, Erosion and Deposition

Make sure you have this foldable:

Key Terms:

Weathering – chemical and physical break down of rocks into sediment

Key Terms (cont’d):

CHEMICAL WEATHERING

THE PROCESS THAT BREAKS DOWN ROCKS BY CHEMICAL CHANGES OR REACTIONS.

This statue has lost finer details in the eyes and lost major details of the nose

Footer text here

MECHANICAL WEATHERINGTHE PROCESS THAT BREAKS DOWN ROCKS BY PHYSICAL MEANS (NO CHANGE IN THE CHEMICAL NATURE OF THE ROCKS).

Grand Canyon is an example of mechanical weathering

Frost or Ice wedging: Exfoliation:

Biological Weathering

• Plant roots grow and break apart rock

Fill in your chart (mechanical)Type of Mechanical Weathering Explanation

Ice Wedging Process that splits rock when water seeps into cracks, then freezes and expands

Exfoliation Extreme high temperatures cause the outside of rocks to crack and flake off

Root Pry Roots enter cracks in rocks, forcing the cracks further apart

Actions of Animals Burrowing in the ground breaks rocks apart

Abrasion Grinding away of rock by other rock particles

Fill in your chart (chemical)Type of Chemical

WeatheringExplanation

Water Water weathers rock by dissolving it

Oxidation Rocks that contain iron, oxidize (rust) and appear red in color

Carbonation Carbon dioxide and water mix to form carbonic acid – over time caves form

Living Organisms Plants produce a weak acid that dissolves rock

Acid Rain Pollutants react chemically with water vapor to form acid rain

Key Terms:

Weathering – chemical and physical break down of rocks into sediment

Erosion – the movement of sediment from one place to another

Deposition – the placement of sediment after being carried from place of origin

Erosion

• First picture - The water weathers the rock and then carries it away from its original location

• Second picture - Utah Canyonlands are created by the wind carrying away rock particles

DepositionExamples:

1. Deposition of this sediment occurs when the waters slows down and the heavier particles drop, forming a delta

2. The sand dunes were created when particles carried on wind were dropped in a new location

Weathering Erosion and Deposition Lab

Do you have your lab page?

This lab will demonstrate different types of weathering, erosion and deposition.

Follow the instructions both on the lab page and at each station. CLEAN UP IS REQUIRED!

Questions at the end are required as part of the reflection and understanding of this lab.

MAKING OBSERVATIONS

What tools do you use to make good observations?

How do you describe observations?

Use descriptive words, for example: don’t just say “white”, say “white with a powdery surface that easily comes off on my hand”.

Lab Expectations

Let’s read the top of the page.

You will be on a time limit for each station.

Lab Expectations

Station Instructions – notice CLEAN UP portion of the station??

Lab Stations 1-3

Stations need to look like this BEFORE your time is up at this station.

DO NOT be the group that holds everyone else up!

You MAY NOT leave your station to rotate to the next one if your current station is not clean!

Lab Stations 4-6

Work in your table groups

• Start at the station you are assigned. When the timer goes off, move to the next station in numerical order.

http://www.online-stopwatch.com/

To complete the lab…

•Complete questions throughout the lab.

•This is due next class!