What is the Earth s interior like?

Similar documents
Layers of The Earth and Plate Tectonics. Learn it, know it, love it.

Topic 5: The Dynamic Crust (workbook p ) Evidence that Earth s crust has shifted and changed in both the past and the present is shown by:

Earthquakes & Volcanoes

12.2 Plate Tectonics

Volcano: a weak spot in the crust where molten material or magma comes to the surface

Outcome C&D Study Guide

Moho (Mohorovicic discontinuity) - boundary between crust and mantle

Earth s Layers p.3 Basic Inner Earth Characteristics

4 Deforming the Earth s Crust

FORCES ON EARTH UNIT 3.2. An investigation into how Newton s Laws of Motion are applied to the tectonic activity on Earth.

Features of Tectonic Plates

Earth and Space Science Semester 2 Exam Review. Part 1. - Convection currents circulate in the Asthenosphere located in the Upper Mantle.

Theory of Plate Tectonics

When Mount St. Helens erupted, trapped gases caused the north side of the mountain to explode. Volcanic ash was ejected high into the atmosphere.

22.4 Plate Tectonics. Africa

Earth Systems, Structures and Processes

Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

FORCES ON EARTH. An investigation into how Newton s Laws of Motion are applied to the tectonic activity on Earth.

Volcanoes. Volcanic eruptions can be more powerful than the explosion of an atomic bomb.

Section 1: Earth s Interior and Plate Tectonics Section 2: Earthquakes and Volcanoes Section 3: Minerals and Rocks Section 4: Weathering and Erosion

Earth s Structure. Earth has 4 layers. The inner core, outer core, mantle and crust. How do we know???

Volcanoes. Presented by Kesler Science

Types of Volcanoes KEY CONCEPT: TECTONIC PLATE MOTIONS CAN RESULT IN VOLCANIC ACTIVITY AT PLATE BOUNDARIES.

Earth is over 1200 km thick and has four distinct layers.

Plate Tectonics. Chapter 8

TAKE HOME EXAM 8R - Geology

Chapter 7: Volcanoes 8/18/2014. Section 1 (Volcanoes and Plate Tectonics) 8 th Grade. Ring of Fire

Unit 4 Lesson 4 Volcanoes. Copyright Houghton Mifflin Harcourt Publishing Company

Earth has more than 600 active volcanoes. An active volcano is one that has erupted within recorded history.

The Theory of Plate Tectonics

Structure of the Earth

Unit Topics. Topic 1: Earth s Interior Topic 2: Continental Drift Topic 3: Crustal Activity Topic 4: Crustal Boundaries Topic 5: Earthquakes

TEST NAME:Geology part 1 TEST ID: GRADE:06 - Sixth Grade SUBJECT:Life and Physical Sciences TEST CATEGORY: My Classroom

Chapter 7 Plate Tectonics. Plate tectonics accounts for important features of Earth s surface and major geologic events.

Earth s Dynamic Surface

Earth s Interior HW Packet HW #1 Plate Tectonics (pages )

Ch12&13 Test. 3. Where does the first motion of an earthquake occur? a. fault c. epicenter b. focus d. locus

PLATE TECTONICS Chapter 4 Notes

Chapter 5 Notes: Plate Tectonics

In 1912 Alfred Wegener proposed Continental Drift the continents have moved over time the continents were part of one giant landmass named Pangaea.

Earthquakes = shaking of Earth because of a rapid release of energy

In order to study Plate Tectonics, we must first

Unit 5: Plate Tectonics

Earth Systems, Structures and Processes

I. Earth s Layers a. Crust: Earth s outside layer. Made of mostly rock. i. Continental: er; made of mostly granite, forms the continents and shallow

Ch. 9 Review. Pgs #1-31 Write Questions and Answers

EARTH SCIENCE KESSEL

Sir Francis Bacon, 1620, noted that the continental coasts on opposites sides of the Atlantic fit together like puzzle pieces.

Mohorovicic discontinuity separates the crust and the upper mantle.

Topography the natural and human features of the Earth s surface. ie. Surface features need to understand difference between relief and elevation

Continental Drift. & Plate Tectonics

Chapter 22: Earth s Interior

Plate Tectonics. Earth has distinctive layers - Like an onion

sonar seismic wave basalt granite

Layers of the Earth Date: SWABT: Identify and describe the layers of the Earth and their characteristics

Plate Tectonics. Chapter 5

A Volcano is An opening in Earth s crust through

Refer to the map on page 173 to answer the following questions.

Plate Tectonics CHAPTER 17

Unit 11: Plate Tectonics

Objectives: Describe how volcanoes can affect people. Describe conditions that cause volcanoes. Describe the relationship between volcanoes and Earth

Earth Movement and Resultant Landforms

Directed Reading. Section: Volcanoes and Plate Tectonics

Directed Reading. Section: The Theory of Plate Tectonics. to the development of plate tectonics, developed? HOW CONTINENTS MOVE

Earth s Changing Surface

Plate Tectonics IDEA THAT EARTH S SURFACE IS BROKEN INTO PLATES THAT MOVE AROUND. Fault = fracture in the crust where the movement has occurred

Name Date Class. How have geologists learned about Earth s inner structure? What are the characteristics of Earth s crust, mantle, and core?

Study guide chapter 9

Effects of Eruptions. Most active in the world Kilauea, Hawaii.

UNIT 11 PLATE TECTONICS

UNIT 4: Earth Science Chapter 12: Earth s Internal Processes (pages )

CONTENT. A. Changes in the Crust Facts Changes Construction and Destruction. B. Continental Drift What is it? Evidence

EARTH S INTERIOR, EVIDENCE FOR PLATE TECTONICS AND PLATE BOUNDARIES

Chapter Review USING KEY TERMS. asthenosphere uplift continental drift. known as. tectonic plates move. object. UNDERSTANDING KEY IDEAS

Ch 9.1 Notes. Objective: Be able to explain the theory of plate tectonics and be able to explain evidence that supports it.

3.2 Notes: Volcanoes Form as Molten Rock Erupts

Tectonic Plates Test Study Guide Answers

UNIT SIX: Earth s Structure. Chapter 18 Earth s History and Rocks Chapter 19 Changing Earth Chapter 20 Earthquakes and Volcanoes

The Structure of the Earth and Plate Tectonics

Name Date Class. Directions: Use the diagram below to answer question Florida Progress Monitoring and Benchmark Assessments

Introduction to Earth s s Spheres The Benchmark

C Earth's Formation and Structure

Earth s Interior StudyGuide

Volcanoes. Table of Contents Volcanoes and Plate Tectonics Volcanic Eruptions Volcanic Landforms

PLATE TECTONICS 11/13/ Investigations of glaciers also indicated that the land masses on Earth were once a supercontinent.

World Geography 3202 Unit 1. Ch. 1: Landform Patterns and Processes

CONTINENTAL DRIFT THEORY

A physical feature of the Earth s surface

Dynamic Crust Practice

Alfred Wegener: continental drift theory Continents move around 200 mya Pangaea (pan = all, gaea= earth) fg 12.8 p. 508

Plate Tectonics. Continental Drift Sea Floor Spreading Plate Boundaries

10/27/2014. Before We Begin, You Need to Understand These Terms: Earth s Structural Key Elements & the Hazards of Plate Movement

05/22/15. Tectonic plate (Noun) Plate tectonics (Noun) Oceanic crust/plate (Noun) Continental crust/plate (Noun) Continental drift (Noun)

PHYSICAL GEOGRAPHY. By Brett Lucas

Directed Reading. Section: Volcanic Eruptions. light in color is called a. felsic. b. oceanic. c. mantle. d. mafic. dark in color is called

L wave Lahar Lava Magma

Continental Drift and Plate Tectonics

Plate Tectonics. Chapter 17. Great Idea: The entire Earth is still changing, due to the slow convection of soft, hot rocks deep within the planet.

Earth, the Lively* Planet. * not counting the life on the planet!

CHAPTER 2 NOTES -FOUNDATIONS OF GEOLOGY-

Transcription:

What is the Earth s interior like?

CRUST Where we live State of matter: solid Characteristics: Rocky, Hard Rock Composition: mostly Aluminum and Silicon Thickness: 0-25 miles thick

Two types of crust 2 types of crust Oceanic crust: below ocean 4 miles thick Continental crust: Below the continents, mostly granite 18-25 miles thick,

MANTLE State of matter: Semi-solid Characteristics: hot, dense, semi-solid Pressure and temperature increase as you go deeper Convection (heat) currents cause plates to move Rock Composition: mostly Iron and magnesium Thickness: 1,800 miles 80% Of Earth s volume

Three layers of Mantle Three layers: Lithosphere Uppermost layer relatively cool, rigid rock Made up of 7 large moving pieces and some smaller moving pieces called tectonics plates Asthenosphere- middle layer softer, weaker rock, flows slow like taffy Mesosphere bottom layer stiff rock

CORE State of matter: Inner core Solid Outer core- Liquid Characteristics: very high pressure Very hot - 5500 c Rock composition: Iron and Nickel

Two layers of the core Two Layers Outer Core = hot liquid metal 1,430 miles thick Rock - nickel and iron alloy Inner core = solid metal 745 miles thick Rock - iron http://www.youtube.com/ watch?v=3mfr2cc3erk &feature=related http://www.youtube.com/watch?v=q9j1xgax

Practice Quiz Question Can you label the following layers?

Why is the interior of the Earth so hot? There are three main sources of heat in the deep earth: Heat from when the planet formed Frictional heating- caused by denser core material sinking to the center of the planet Heat from the decay of radioactive elements. The interior contains radioactive isotopes. When these isotopes break apart, they release energy in the form of heat.

The Theory of Plate Tectonics The idea of plate tectonics was first introduced by Alfred Wegener in the early 1900 s but it was not widely accepted until the 1960 s. Plate tectonics is the theory that pieces of the Earth s lithosphere, called plates, move about slowly on top of the asthenosphere.

Forces causing plate movement The physical force driving these plates is not fully understood, however it appears that the lithosphere plates glide slowly on top of a semi-solid layer of the upper mantle known as the asthenosphere.

Forces causing plate movement Convection currents, due to the temperature differences between the mantle and the crust, hot matter will rise to the surface and cool matter will drop, which causes the plates above it to move and shift.

The Plate tectonics theory explains: The continents were once connected together in a large continent called Pangaea meaning all land. The continents have been and are still moving at a rate of 1-16 cm a year. http://www.classzone.com/books/earth_science/terc/c ontent/visualizations/es0806/es0806page01.cfm?chapt er_no=visualization

Plate Tectonics

Movement of the Plates

http://www.montereyinstitute.org/noaa/lesson01.html

Evidence of Plate movement 1. Matching Coastlines (puzzle) Eastern coast of South America and Western coast of Africa fit together

Gondwanaland: matching coastlines Matching Coastlines

Evidence of Plate tectonics 2. Shared Fossils: Same kinds of animals lived on continents that are now oceans apart

Evidence of Plate tectonics 3. Paleomagnetism Iron materials on ocean floor align themselves parallel to Earth s magnetic poles. A permanent records of magnetism field. Rocks retain memory of magnetic field when they cool Polar Reversals - Different aged rocks show that the polarity of the magnetic pole has reversed many times in the past.

Earth s magnetic poles helped to determine the plate boundaries

Evidence of Plate tectonics 4.Matching Glaciers

Evidence of Plate tectonics 5. Rocks strata (layers) match

Evidence of Plate tectonics 6. Matching Mountain ranges Appalachian Mountains, Greenland range, British Idles and Caledonian Mountains

Mechanisms of Plate Tectonics Movement Patterns: 1. Move towards each other 2. Move away from each other 3. Slide alongside each other Plate move about 1-16 cm/year

Earth s Tectonic Plates

Plate Boundaries There are three types Divergent boundaries Convergent Boundaries Transform Boundaries

Divergent Boundaries Two plates move apart and creates a gap of newly formed rock. In the ocean: Ridges are created as lava pushes its way up through the crust. Ex. Mid-Atlantic ridge Sea Floor spreading process where new oceanic crust is made as magma rises and old crust moves away.

Divergent Boundary

Divergent Boundary On the continent: Rift Valley: When the plates move away, the land between drops and creates a valley http://www.montereyinstitute.org/noaa/lesson02.html

Convergent Boundary Two plates move towards each other In the ocean: Subduction: As seafloor spreading occurs old oceanic plates sink into the mantle and creates a trench This destroys old oceanic crust Trench : where a plate sinks creating a depression

Plate movements

Convergent Boundary On the continent: Continental plates moving towards each other can form mountains Example: Himalayas

Building the Himalayas

Boundaries Review: Divergent Boundaries Plates Move away from each other Continent: Form Rift Valleys Ocean: Mid ocean ridges Convergent Boundaries Plates move towards each other Continent: Mountain ranges Ocean: Trenches

Transform Fault Plates slide horizontally in opposite directions. Rock is neither created or displaced, just shifted. Often creates earthquakes

San Andres Fault: Transform Fault

What is an Earthquake? Movement of the earth s lithosphere that occurs when rocks suddenly shift, releasing stored energy. As plates move, the rocks along their edges experience immense pressure and eventually rocks are broken along the fault line. The energy is released as seismic waves. A tsunami is a large sea wave created by an underwater earthquake, volcano or landslide.

Earthquake Terms Fault Break in a mass of rock along which movement occurs Fold Bending in the layers of rock Focus location beneath the earth s surface where an earthquake starts Epicenter Location on the earth s surface directly above the focus

Types of Stress Compression - squeezes rock until it breaks. Tension pulls on the crust stretching rock Shearing pushes a mass of rock in two opposite directions

Normal Fault One block of rock lies above the fault and one block below it Caused by tension Types of Faults Reverse Fault The bottom block slides up past the upper block Caused by compression Strike Slip Rocks slide past each other Caused by shearing

Waves Energy from earthquakes is transferred through the Earth by waves P waves - Longitudinal Waves Primary wave - First wave to reach the recording station. The fastest moving wave through solid or liquid The wave looks like a compressed spring and then you release the spring.

Waves S Wave = Transverse Waves Secondary wave Move more slowly through rock Wave looks like a rope being shaken up and down Light and electromagnetic radiation Cannot travel through liquid

Waves Surface Waves These waves move on the surface of the Earth. Move slower than S and P waves but produce larger ground movements and greater damage. They can move up and down, side to side, or like an ocean wave coming in.

Measuring an Earthquake Seismology: Study of earthquakes. Seismograph is a tool used to record P waves, S waves, and Surface waves. Based on the recordings, we can determine how strong the earthquake was.

Seismology Three seismographs are necessary to locate the epicenter of an earthquake 1. P waves: small zigzag lines 2. S waves: larger, more ragged lines 3. Surface waves: arrive last and make the largest lines

How do geologists use seismographs to investigate the Earth s interior?? Certain waves move at different speeds and through certain material. (S waves can not go through liquid.) Because of this, we have figured out part of the core is liquid, the mantle is semi-liquid, etc.

Rating Earthquakes Richter Scale: measures the magnitude of earthquakes Moment Magnitude Scale Measures the amount of energy released by earthquake each unit represents 32X increase in the energy released. Modified Mercalli scale rates the type of damage and other effects noted by observers Largest Ever recorded 9.5 in Chile 1960

Modified Mercalli

Richter Scale

Example In Alaska, 1964, there was an earthquake with a magnitude of 8.4. An earthquake with a magnitude of 8 releases 810,000 times as much energy as an earthquake with a magnitude of 4.

Scale vs. Damage The scales cannot predict amount of damage. Damage depends on: Distance between populated areas and the epicenter. The depth of the focus. The physical properties of the surface rocks.

Compare the occurrence of earthquakes with the plate boundaries. Where are the earthquakes happening? (Look at the black, green and red dots.)

An opening in the Earth s crust through which magma reaches Earth s surface.

Volcanoes Can be very destructive Have also been beneficial: Atmospheric gases Water New land Energy source Information about the inside of the Earth

Structure of a volcano Magma chamber where magma collects Pipe Where magma rises to the surface Conduit/Vent Tubelike structure from below the surface emerging to the surface as a vent. Crater Connected to the conduit, it is the bowl shaped pit at the top of the volcano Caldera depression at top of volcano caused by a shell collapse Lava Dome protrusion from extra lava flows

a. caldera

Mount St. Helen s c. lava dome Lava dome

Why volcanoes erupt Similar to shaking a pop bottle Magma is under the surface is under a lot of pressure from dissolved gases (water vapor and CO2) As it approaches the surface, the lowered pressure causes the gases to expand rapidly. An eruption occurs when the gases bubble out through a crack in the crust.

Magma vs Lava What is the difference?

Magma Under the Earth s surface. Forced upward through the vent

Lava When magma reaches the surface Magma cools and hardens to form lava fields

Eruptions Volcanoes erupt explosively or quietly depending on the magma. Explosive eruptions lava and hot gases are hurled outward and lava solidifies quickly Quiet eruptions lava erupts in a stream of easily flowing lava

Pahoehoe Lava flow Hot fast moving with ropelike surface

AA lava flow Cooler, slow lava with a chunky, crumbly appearance

Pillow lavaoozing lava beneath the water surface

Eruptions Tephra is what volcanoes throw into the air it is classified by size Ash/Dust smallest fragments of tephra Blocks Largest size pieces Cinders igneous rock similar to pumice Pyroclastic Flow Rapidly moving clouds of tephra with hot gas (up to 700 ) at speeds up to 80 mph

Types of Volcanoes Shield Volcanoes Broad, gentle sloping shape Quiet, mild eruptions Largest volcanoes Ex. Mauna Loa

Types of Volcanoes Composite Volcanoes Tall with steep sides Built from alternating layers of ash, cinder and lava Explosive eruptions Often have secondary vents Ex. Mt Fuji, Japan

Types of Volcanoes Cinder Cone Smallest and most abundant Steep sides Explosive eruption is entirely of ash and cinders Active only for a short time, then dormant Ex. Paracutin, Mexico

Sunset crater, AZ

Mt. Pelée, Martinique

Locations of volcanoes Two places most volcanoes reside Plate boundaries Hot spots Hot spots occur in the middle of plates - region where hot rock extends from deep within the mantle (ex. Hawaii, Iceland)

80% of all volcanoes are located in the Ring of Fire

Active, dormant, extinct An active volcano is a volcano that has had at least one eruption during the past 10,000 years. An active volcano might be erupting or dormant. An erupting volcano is an active volcano that is having an eruption. A dormant volcano is an active volcano that is not erupting, but supposed to erupt again. An extinct volcano has not had an eruption for at least 10,000 years and is not expected to erupt again in a comparable time scale of the future.

Mauna Loa 1984 (Photograph by Richard B. Moore)

Hekla, Iceland 1991, photo by Sigurgeir Jónasson

Hekla, Iceland 1991, photo by Ragnar Th. Sigurdsson

Mauna Loa (Peter Francis)

1,900-foot high fountain, Kilauea Iki,1959 (National Park Service Photograph)

Stromboli, April 1996

Vulcano,Vulcanello, and Lipari (Peter Francis)

1980 eruption of Mount St. Helens (photo courtesy of J.M. Vallance)

Mt. St. Helens most recent eruption

Eyjafjallajökull Iceland - 2010