Notebook Pages, Assignments, Etc.
Notes: Forces Shaping Earth (Ch. 10, Sect. 1)
Earth’s Moving Plates
Notes: Chapter 10, Section 2
G. Mountains form in different ways.
a. igneous & metamorphic rock left
1. can erode leaving sharp peaks & ridges
4. Over time, layers of lava can form a cone shaped volcanic mountain.
a. some form when plates sink into the subduction zone (melting occurs)
b. magma (less dense) forced upward toward the surface
c. erupts & lava/ash pile up over time = volcanic mountain (subduction volcano)
5. Hot spots formed by plumes of magma in the mantle can cause underwater volcanic mountains
a. plates travel over hot spots = series of volcanoes (Hawaiian Islands)
b. magma forms deeper in mantle than subduction volcanoes
c. larger with more gently sloping sides than subduction volcanoes
H. Isostacy principle indicates Earth’s lithosphere (crust & uppermost mantle) floats on the aethenosphere (upper mantle)
1. Earth’s crust is thicker under mountains.
2. If uplifting continues, crust under mountains will become thicker & extend further into the mantle.
3. When mountains stop forming, erosion/weathering begins.
4. Mountains lowered due to erosion/weathering & crust rises because of less weight.
a. crust no longer as thick
5. Icebergs behave in a similar way as they melt. (less & less below the water as they melt)
Study Guide “Forces Shaping Earth.”
To prepare for the chapter test, the following strategies should be helpful:
Notes: Weathering & Erosion (Ch. 11, Sect. 1)
Section 1: Weathering & Soil Formation
Name ____________________
Date _____________________
Period 1 2 3 6 7 8
Activity “Chalk”
Instructions:
Name ____________________
Date _____________________
Period 1 2 3 6 7 8
Questions, pg. 321
Answer the following questions in complete sentences.
Notes: Ch. 11, Sect. 2: Erosion of Earth’s Surface
Earth’s Moving Plates
- Geologists use earthquakes & surface rocks to indirectly observe Earth’s interior.
- Seismic waves change speed/direction depending on the density of the material they travel through.
- Primary (P) waves travel 6 km/sec. & can travel through liquids & solids.
- Secondary (S) waves travel 4 km/sec. & travel through solids (but not liquids).
- Forces bring rocks formed deep within Earth to the surface.
- Evidence suggests Earth is formed of different materials in layers.
- Earth has four layers.
- Inner core – solid, dense iron core (very hot)
- Outer core – molten metal above the inner core
- Mantle – solid layer that flows slowly like putty
- Crust – outermost layer (We live here.)
- Earth’s structure – theories based on physical properties of density, temperature, & pressure that change with depth
- Earth’s moving plates are sections of the lithosphere (rigid upper part of the mantle & crust).
- Plate boundaries are edges where plates meet.
- Tension can pull plates apart, resulting in new lithosphere forming in the gaps.
- Mid ocean ridges & rift valleys
- Colliding plates (compression) could cause mountains to form as rock crumbles/folds.
- Himalayan & Andes mountains
- Subduction occurs when a denser plate sinks under a less dense plate.
- Continental/oceanic or oceanic/oceanic
- Volcanoes and/or volcanic islands can form
- Shearing causes faults & earthquakes as two plates slide past each other. (transform boundaries)
- San Andreas Fault in California
- Plate movement theory – convection in the mantle circulates material & moves plates.
- Ridge-push at mid-ocean ridges causes plates to slide down the slope.
Notes: Chapter 10, Section 2
G. Mountains form in different ways.
- Fault – block mountains form from huge tilted blocks of rock separated from surrounding rock by large faults
- rock layers pulled in opposite directions
- large blocks slide downward = peaks & valleys
- ex.: Teton Range in Wyoming
- Folded mountains – form by compression forces (plates colliding) folding rock layers
- Appalachian mountains formed 250 – 300 MYA
- North American & African plates collided
- higher than the Rocky Mountains at one time
- erosion has rounded & lowered them over time
a. igneous & metamorphic rock left
1. can erode leaving sharp peaks & ridges
4. Over time, layers of lava can form a cone shaped volcanic mountain.
a. some form when plates sink into the subduction zone (melting occurs)
b. magma (less dense) forced upward toward the surface
c. erupts & lava/ash pile up over time = volcanic mountain (subduction volcano)
5. Hot spots formed by plumes of magma in the mantle can cause underwater volcanic mountains
a. plates travel over hot spots = series of volcanoes (Hawaiian Islands)
b. magma forms deeper in mantle than subduction volcanoes
c. larger with more gently sloping sides than subduction volcanoes
H. Isostacy principle indicates Earth’s lithosphere (crust & uppermost mantle) floats on the aethenosphere (upper mantle)
1. Earth’s crust is thicker under mountains.
2. If uplifting continues, crust under mountains will become thicker & extend further into the mantle.
3. When mountains stop forming, erosion/weathering begins.
4. Mountains lowered due to erosion/weathering & crust rises because of less weight.
a. crust no longer as thick
5. Icebergs behave in a similar way as they melt. (less & less below the water as they melt)
Study Guide “Forces Shaping Earth.”
To prepare for the chapter test, the following strategies should be helpful:
- Reread Ch. 10 “Forces Shaping Earth.”
- Study your notes.
- Review your Science Notebook beginning with # 6.
- Study Section Review questions, pgs. 297 & 305.
- Study the Chapter Review questions, pgs. 310 – 313.
- Identify where earthquakes usually take place.
- Identify/discuss the different types of plate collisions.
- Describe the formation of/give an example of fault – block mountains.
- Describe the formation of/give an example of folded mountains.
- Describe the formation of/give an example of volcanic mountains.
- Discuss the similarities/differences between subduction & underwater volcanoes.
- Identify/discuss characteristics of the Earth’s layers.
- Discuss what happens to temperature & pressure as you move from the Earth’s crust toward the inner core.
- Discuss the effect of Earth’s moving plates on the positions of the continents.
- Discuss ridge push & slab pull.
- Discuss the principle of isostacy as it applies to mountains & the thickness of Earth’s crust below them. Discuss what happens to Earth’s crust as uplifting continues.
- Discuss what happens to the thickness of Earth’s crust as the mountains are eroded away.
- Discuss how geologists have used information they gathered by studying earthquakes & rocks at the surface to learn about the layers of the Earth.
- Discuss the difference between primary & secondary seismic waves.
- Discuss the plate movement theory.
- Discuss three types of movement that can occur where two plates meet.
- Discuss transform boundaries. (shearing)
Notes: Weathering & Erosion (Ch. 11, Sect. 1)
Section 1: Weathering & Soil Formation
- Weathering – natural process that causes rock to break down
- Mechanical weathering – breaks rock into smaller pieces without changing them chemically
- Ice wedging – the freezing/thawing cycle that breaks rock apart
- Water expands when it freezes = pressure on the rocks
- Plant roots and burrowing animals exert pressure on rocks
- Chemical weathering causes the chemical composition of rock to change
- Carbonic acid from water & carbon dioxide, reacts chemically with rocks such as limestone & marble
- Tannic acid, formed from a plant’s (incl. mosses) release of tannin, dissolves some rock minerals
- Remaining rock is weakened & can break into smaller pieces
- Oxygen can cause rocks containing iron to rust in the process of oxidation (iron oxide)
- Remaining rock is weakened & can break apart
- Soil – mixture of weathered rock, organic matter, water, & air that supports plant life
- Parent rock affects what kind of soil develops
- Sandstone = sandy soil
- Topography influences soil development
- Steep hillside = little chance of soil developing
- The climate in tropical regions increases the rate of weathering forming soil (faster than in deserts)
- Soil in deserts contains little organic matter
- Soil formed in warm, humid climates contains more organic matter (humus)
- Rocks take time (perhaps thousands of years), to weather into soil
- Soil becomes less like parent rock over time
- Plant materials affect soil development
- Lichens grow directly on rock
- Nutrients taken from the rock
- Thin layer of soil forms
- Once soil is formed, many types of plants (grasses/trees) grow
- Roots further break down the parent rock
- Dead plant material (leaves, etc.) accumulates
- Adds organic matter to the soil
Name ____________________
Date _____________________
Period 1 2 3 6 7 8
Activity “Chalk”
Instructions:
- Use the dissecting probe to scratch your name in the piece of chalk.
- Carefully, put a few drops of vinegar on the area of the chalk with your name. Observe carefully (you need to use a magnifying glass), and record your observations. ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
- Chalk is a type of sedimentary rock, and the vinegar is a slightly acidic solution. Describe how your observations today are similar to a type of chemical weathering of rock. Use your notes, and be specific. ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Name ____________________
Date _____________________
Period 1 2 3 6 7 8
Questions, pg. 321
Answer the following questions in complete sentences.
- Describe how rocks are mechanically weathered. (2)
- ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
- Name agents of chemical weathering. (2)
- _______________________________________________________________________________________________________________________________________________________________
- Explain how carbonic acid weathers rock.
- ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
- Explain how soil forms. What factors are important? (5)
- ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
- How could climate affect the rates of mechanical weathering? What about chemical weathering? How are the two kinds of weathering related?
- ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
- Compare/contrast mechanical weathering caused by ice & growing roots
Notes: Ch. 11, Sect. 2: Erosion of Earth’s Surface
- Erosion – wearing away & removal of rock; occurs because of gravity, ice, wind, & water (agents)
- Mass Movement – gravity pulls rock or sediment down slopes
- Creep – sediments move downhill slowly
- Freezing/thawing of soil & gravity involved
- Slump – rock or sediment moves downhill along a curved slope
- Rock slide – rock layers break loose & slide downhill
- Mudflow – mass of wet sediment that flows downhill over the ground surface
- Ice forms continental & valley glaciers
- General erosion - glaciers remove loose pieces of rock or as dragged rock scratches rock underneath the glacier
- Glaciers can form cirques or steep peaks in mountains, create lakes, or totally remove rock from the surface
- Glaciers deposit sediment
- Till – a mixture of different sized particles ranging from clay to boulders, deposited directly from the bottom of the glacier
- Outwash – sand & gravel deposits moved by rivers from melting glaciers
- Wind – blows small particles from Earth’s surface in a process called deflation
- Abrasion – forms pits in rock or polishes surfaces smooth as sediments are blown by strong winds
- Dunes – form as the wind is slowed as it blows around irregular features such as rock or vegetation & deposits the sediment it carried
- Loess (fine silt) – often collects downwind of large deserts or near glacial streams
- Runoff – water flowing on Earth’s surface causes erosion
- Sheet flow – water flows downhill as a thin sheet often carrying loose sediment grains
- Rills & gullies – channels cut into Earth’s surface & are formed as runoff carries sediments along
- Streams have water flowing through them continuosly; eventually flow into the ocean or a large lake
- Moving water in streams – the most important agent of erosion
- Shape more of Earth’s surface than ice, wind, or gravity