Unit 4 : Weathering, Erosion and Landscapes

Earth Science Picture of the Day http://epod.usra.edu/

At the end of this unit You will be able to Describe the differences in settling rates due to density, shape and size Describe the factors that increase weathering Interpret graphs and diagrams relating to erosion Describe and label, old age, mature and youthful streams Label erosion and deposition in a river channel Relate velocity to slope and discharge of a stream Define: erosion, deposition, weathering Create a profile Read and interpret topographic maps

Laboratory Activities for this unit: Landscape Regions of NYS Slope, Rise over run (gutter) Weathering (top secret) Weathering rocks (shake, shake) Sediment deposition

Turn to the table of contents and copy this down Unit 4 Surface Processes p 47-49 Vocabulary p 50 Types of weathering p 51 Weathering rates p 52 Weathering Agents p 53 Settling rates p 54 Water velocity p 55 Stream evolution p 56 Landscapes

Now… turn to page 46 and number up to page 56 Turn to page 47… you will be writing 22 vocabulary terms. You have pages (47-49) to write them on… I gave you extra room in case you need it.

Vocabulary page 47-49 in notebook Abrasion: To rub, grind or wear away at rock surfaces and sediment Chemical Weathering: process by which chemicals break rocks down and make new materials  Erosion: carrying away of sediment to a new location Mass movement: mudslides, landslides, avalanche, due to gravity

Vocabulary page 47-49 in notebook Physical weathering: breakdown of rock with no change in composition  Sediment: particles that are formed by the erosion of rocks and materials  Stream abrasion: rounding, smoothing and size reduction because of rolling, sliding and bouncing along the bottom  Tributary: a small stream or river that joins a larger stream or river 

Vocabulary page 47-49 in notebook Watershed: an area that is drained by a stream Weathering: chemical and physical changes of a rock or material at or near the surface  Deposition: sediment is released dropped or settled out from an erosional system  Drumlin: a long narrow streamlined oval mound of unsorted sediment formed by a glacier 

Vocabulary page 47-49 in notebook Escarpment: a steep slope or cliff in layered rocks often formed when a rock is resistant to weathering and erosion Landscape: features of the earth’s surface  Mountain: an area of high elevation, with distorted rock structure  Plain: an area of low elevation, with horizontal rock structure

Vocabulary page 47-49 in notebook Plateau: an area of high elevation with undistorted horizontal rock structure  Ridge: a long, narrow, high, steep sloped part of a landscape  Stream drainage pattern: the shape of the stream course in an area as viewed from above 

Vocabulary page 47-49 in notebook Uplifting forces: forces that cause the earth’s surface to be raised up Sorted sediment: a deposit of sediment based on similar size, shape, or density Unsorted sediment: a deposit of sediments that are mixed in size, shape and density

Weathering = a break down = a change P 50 in notebook I. weathering(definition): a physical and chemical process that changes how rocks and minerals look on the surface of the earth Weathering = a break down = a change

Weathering A. 2 types of weathering 1. Physical weathering broken down into smaller pieces, hammer, gravity P 50 in notebook

a. Changed into something else, rust, dissolving etc… Weathering P 50 in notebook 2. Chemical weathering a. Changed into something else, rust, dissolving etc…

Weathering P 50 in notebook B. Weathering rates (Foldable) How do I make weathering happened faster? (a faster rate of time?) 1. Softer rocks= faster 2. Size, smaller = faster 3. Longer the exposure= more weathering

C. Weathering agents / cause erosion P 51 in notebook Sorted the sediments wind – sand particles blast at the surface a. Pitted or frosted appearance

C. Weathering agents / cause erosion P 51 in notebook Sorted the sediments 2. water – abrasion from rolling and hitting other particles a. Rounded and smooth

C. Weathering agents/ cause erosion P 51 in notebook The 2 “W’s” sort by size

The movement of soil, rocks, minerals from 1 location to another. D. Erosion P 51 in notebook The movement of soil, rocks, minerals from 1 location to another.

C. Weathering agents/ cause erosion P 51 in notebook Unsorted sediments glaciers- gouge out the sediment below it. a. “U” shaped valleys, striations or scratches on the bedrock Visualizations and features

C. Weathering agents/ cause erosion P 51 in notebook Unsorted sediments gravity- makes the objects fall a. jagged edges - angular Visualizations and features

C. Weathering agents/ cause erosion P 51 in notebook The 2 “G’s” do not sort

E. Settling rates (foldable) P 52 in notebook What will make a particle fall to the bottom faster than another? 1. Density a. more dense = settles faster 2. Shape a. rounder it is the faster it settles Analogy: Cannon ball vs Belly flop

E. Settling rates (foldable) P 54 in notebook What will make a particle fall to the bottom faster than another? 3. Size a. larger it is the faster it settles or falls to the bottom Analogy: Big kid vs. Little kid on a water slide ride (see page 31 of notebook)

F. Water velocity P 54 in notebook 1. What a stream or river can transport is based on the size, density and velocity of the water. (page 6, ESRT)chart a. stream traveling at 700 Cm/ sec can carry _______________

Page 6, ESRT Above the line Cannot carry Below the Line, CAN carry Return to slide

Side View Top View F. Water velocity Friction with sides or banks P 55 in notebook 2. Straight stream (foldable) Friction with sides or banks Friction with air and bottom Side View Top View

F. Water velocity P 55 in notebook 2. Straight stream (foldable) a. fastest flow in the middle of the channel b. fastest flow right below the surface of the water

F. Water velocity P 56 in notebook Fastest flow on the outside of the bend erosion Slow on the inside Deposition material gets deposited

F. Water velocity b. inside of bend: slow flow, deposition P 56 in notebook a. Outside of bend: fastest flow, erosion b. inside of bend: slow flow, deposition Analogy: Go carts, Running the mile with a friend meandering stream #2 Oxbow lake

G. Stream Evolution P 57 in notebook 1. Youthful streams a. straight- no meanders b. Cuts down-Lots of erosion c. “V” shaped valleys d. Fast flow

G. Stream Evolution 2. Mature Streams a. a few meanders or bends P 57 in notebook 2. Mature Streams a. a few meanders or bends

G. Stream Evolution P 57 in notebook 3. Old age streams a. lots of meanders or bends b. Oxbow lakes

H. Landscapes 1. Mountains a.high elevation- or high relief b.usually made of deformed rocks, such as metamorphic, or igneous P 57 in notebook

H. Landscapes 2. Plains a. low elevation- little to no relief b. flat, typically sedimentary c. usually surrounding bodies of water P 57 in notebook

H. Landscapes 3. Plateau: flat topped mountains a. sedimentary rock P 57 in notebook