The Dynamic Earth
description
Transcript of The Dynamic Earth
![Page 1: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/1.jpg)
The Dynamic Earth
Environmental ScienceMs. Moore
1/28/13
![Page 2: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/2.jpg)
The Earth as a System
• The Earth consists of rock, air, water, and living things that all interact with each other– Geosphere: rock– Atmosphere: air– Hydrosphere: water– Biosphere: living things
![Page 3: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/3.jpg)
The Geosphere
• The solid part of the Earth that consists of all rock, as well as soils and loose rocks on the Earth’s surface, makes up the geosphere.
• Most of the geosphere is located in Earth’s interior.
![Page 4: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/4.jpg)
Discovering Earth’s Interior
• How do we study the interior Earth?– Seismic waves: travel through the Earth’s interior
during an earthquake– We use the same thinking when figuring out if a
melon is ripe.
![Page 5: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/5.jpg)
The Earth’s Composition
• Using chemical properties, scientists divide Earth into 3 layers:– Crust: composed of light elements; makes up less
than 1% of the Earth’s mass; thinnest layer, 5-8km thick beneath oceans and 20-70km thick beneath continents
– Mantle: beneath crust; makes up 64% of Earth’s mass; 2,900km thick; made up of rocks
– Core: Earth’s innermost layer; densest elements; radius of 3,400km
![Page 6: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/6.jpg)
Structure of the Earth• Using physical properties, scientist divide the
Earth into 5 layers:– Lithosphere: outer layer; 15-300km thick; includes
the crust and uppermost mantle; divided into tectonic plates
– Asthenosphere: layer beneath lithosphere; plastic, solid layer of the mantle made of rock
– Mesosphere: lower part of the mantle; 2,550km thick– Outer Core: 2,200km thick; outer shell of core; made
of liquid nickel and iron– Inner Core: 1,228km radius; sphere of solid nickel and
iron at the center of the Earth
![Page 7: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/7.jpg)
Activity
• Ms. Moore will divide you into 5 groups
• Create a presentation about the layers of the Earth– Include compositional and physical layers– Include facts about each layer
• Be prepared to present your project to the class
![Page 8: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/8.jpg)
Plate Tectonics
• Lithosphere is divided into pieces called tectonic plates. They glide across the asthenosphere like a chunk of ice drifts across a pond.
• Major tectonic plates:– Pacific– North American– South American– African– Eurasian– Antarctic
![Page 9: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/9.jpg)
Plate Boundaries
• Plates may move away from one another, collide, or slip past one another. The forces produced can cause mountains to form, earthquakes to shake the crust, and volcanoes to erupt.
![Page 10: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/10.jpg)
Convergent Boundary
• A convergent boundary occurs where two plates are pushing toward each other.– The boundary between the Eurasian Plate and the
Indain Plate at the Himalayas– The boundary between the Nazca Plate and the
South American Plate along the west coast of South America
![Page 11: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/11.jpg)
Divergent Boundary
• A divergent boundary marks two plates that are moving apart from each other.– The boundary between the African Plate and the
Arabian Plate in the Red Sea– The boundary between the Pacific and Antarctic
Plates– The mid-Atlantic Ridge, made up of the boundary
between the North American and Eurasian Plates in the North Atlantic, crossing Iceland, and the South American and the African Plates in the South Atlantic
![Page 12: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/12.jpg)
Transform Boundary
• A transform boundary occurs where two plates slide past each other.– The boundary between the Pacific Plate, crossing
New Zealand– The boundary between the Pacific Plate and the
North American Plate in California
![Page 13: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/13.jpg)
Earthquakes
• A fault is a break in the Earth’s crust, when these areas are under great stress, we experience an earthquake.
• The Richter scale is used by scientists to quantify the magnitude of an earthquake.– 2.0 to 9.5
• The majority of earthquakes take place at or near tectonic plate boundaries.
![Page 14: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/14.jpg)
Volcanoes• A volcano is a mountain built from magma (melted rock);
they are often found near tectonic plate boundaries.
• A volcano erupts when the pressure of the magma inside becomes so great that is blows open the solid surface of the volcano.– If a volcano has magma running out of it all the time, then
pressure never builds up.
• Major volcanic eruptions can change Earth’s climate for several years.– Ash and gases reduce the amount of sunlight that reaches the
Earth’s surface drop in average global surface temperature.
![Page 15: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/15.jpg)
Erosion
• The removal and transport of surface material is called erosion.-this is how geologists know that the round topped
Appalachian mountains are older than the jagged Rocky mountains in the west.
• 2 types:– Wind– Water
![Page 16: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/16.jpg)
The Atmosphere• Earth is surrounded by a mixture of gases known as the
atmosphere.– Nitrogen = 78% (volcanic eruptions, dead organisms decay)– Oxygen = 21% (plant production– Others = 1% (Ar, CO2, CH4, and water vapor)
• The atmosphere is pulled toward Earth by gravity.– The atmosphere is denser near the Earth’s surface
Atmosphere Composition
NitrogenOxygenOther
![Page 17: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/17.jpg)
Layers of the Atmosphere• Nearest to Earth’s surface = troposphere– Weather occurs here; Densest layer; Temp drops as
• Above troposphere = stratosphere– Temp increases as ; ozone (O3) reduces UV to Earth
• Above stratosphere = mesosphere– Coldest layer of atmosphere (-93°C)
• Farthest from Earth’s surface = thermosphere– Absorbs radiation; hottest layer (2,000°C); lower thermosphere =
ionosphere = aurora borealis
![Page 18: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/18.jpg)
Energy in Atmosphere
• Energy from sun is transferred in the Earth’s atmosphere by 3 mechanisms:– Radiation: transfer of energy across space (fire
heat)– Conduction: flow of heat from warmer object to
colder object in direct contact (stove)– Convection: transfer of heat by air currents (hot air
rises and cold air sinks)
![Page 19: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/19.jpg)
![Page 20: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/20.jpg)
Greenhouse Effect • Why does your car
get hot on a sunny day?
• The greenhouse effect is the process in which gases trap heat near the Earth.– Without this effect,
it would be too cold for life to exist.
![Page 21: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/21.jpg)
The Hydrosphere
• Hydrosphere– Includes all of the water
on or near the Earth’s surface.
• The Water Cycle– Continuous movement of
water into the air, onto land, and back to water.
![Page 22: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/22.jpg)
Water Cycle
• Evaporation: liquid water is heated by the sun and rises into the atmosphere as water vapor
• Condensation: water vapor forms water droplets on dust particles = cloud formation
• Precipitation: large water droplets fall from clouds as rain, snow, sleet, or hail
![Page 23: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/23.jpg)
Earth’s Oceans
• What are the Earth’s oceans? Put them in order from largest to smallest.– Pacific, Atlantic, Indian, and Arctic.
• What makes up the ocean?
ChlorineSodiumMagnesiumSulfurCalciumPotassiumOther
![Page 24: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/24.jpg)
Ocean Temperature Zones
![Page 25: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/25.jpg)
Biosphere
• Biosphere: where life exists– Uppermost part of the geosphere, most of the
hydrosphere, and the lower part of the atmosphere
![Page 26: The Dynamic Earth](https://reader035.fdocuments.us/reader035/viewer/2022062520/56815ec9550346895dcd4d79/html5/thumbnails/26.jpg)
Lab
• Earthquake Exercise
• Volcano Exercise
• The Water Cycle
• Biosphere Model