2Section 1 Layers of the Earth Objectives:Describe and compare the crust, mantle, and coreDescribe the structure of the lithosphereExplain why matter within the asthenosphere movesMake a model of the earth and its layers
3Skills Warm-up Layer by Layer List different objects that are made up of layers.Classify them based on number, type, and thickness of layers.Do most of the objects contain soft or hard centers?
4Earth’s InteriorEarth’s surface is made up of ______, ______, and _______At one time, people thought earth might be ___________In 1864, Jules Verne wrote “Journey to the Center of the Earth”What do you think is between earth’s surface and its center?
5Earth’s InteriorWhat would you find if you could bore a hole deep into the earth until you reached its center?1. The _________ __________of the materials changes as you go __________2. Materials increase in ________ as you go __________3. __________ and _________ increase with depth, but at different ratesThe way that these factors ________ in the earth’s interior produces ________ with different ________ __________ and different ________ __________
6Layers of the Earth 3 Main Layers based on ___________ properties: ________ – outermost layer of the earth________ – middle layer of the earth________ – innermost layer of the earth
7ActivityWatch parts of Journey to the Center of the Earth
9Chemical Makeup of Layers From _________ to _________:Crust – contains rocky ________ (silicon/oxygen compounds) rich in _________ (Al), _______ (Fe), and ___________ (Mg)Thickness varies from _______to _______Mantle – dense, mostly _____ and ____ _________Makes up ________ of Earth’s volumeMakes up ________ of Earth’s massCore – very dense, mostly two metals: ___ and ___
12Physical Makeup of Layers 3 Main Layers based on ___________ ___________:The _____________ includes the crust and outer mantle – it is strong, cold and rigidThe _____________ is just below in the mantle - it is hot, semi-liquid, and easily deformed (plasticity)The ______________ (mantle) below the asthenosphere – very strong and rigid because temperature isn’t high enough
13Physical Makeup of Layers ______ ______– liquidTemperature overcomes pressureCirculation of molten Fe is source of magnetic field?______ ______– solidVery high pressure overcomes high temperature
14Physical Properties of Layers ____________________ deep inside the earth are ______ __________to melt the silicates and other substances that make it upBut, most of the earth’s interior is not ___________Why????
15Physical Properties of Layers _________ inside the earth offset the high temperatures_______ pressures will not allow the earth’s matter to _______
17Physical Properties_________ between __________ and ________ varies with depth of each of earth’s layersDepending on this balance, matter can be ________, ________, or ___ ____________________ – condition where the right balance of pressure and temperature makes _______ material _______ and ___________, but not completely liquid
18Questions So Far Answer the following 10 questions on a sheet of paper and hand them in at the end of class (use your guided notes)1. How thick is the crust and what does it contain?2. What materials does the mantle contain?3. How much of the earth’s volume does the mantle make up? How much of the earth’s mass?4. Which layer is more dense, the mantle or the core? (Remember D = M/V)5. What materials account for the density of the earth’s core?
19Questions So Far6. Based on their characteristic physical properties, what are the 5 zones of the earth?7. What does the lithosphere include?8. What is the hot, soft, and flowing condition of the asthenosphere called?9. What is the physical condition of the outer core? Why?10. What is the physical condition of the inner core? Why?
21Skills Warm-up Crust: What objects besides the earth have crusts? How are their crusts similar to and different from the earth’s crust?
22Structure of the ____________ Two distinct parts:___________ _______Less dense because of higher percentage of silicon and oxygen, has more aluminumContains rocks called rhyolite and graniteMore dense and darker in colorContains rocks called basalt and gabbroWhich varies in thickness more?
23Movement in the ______________ Material is ________ and ________ – like hot tarIntense heat from Earth’s core causes this material to _____________Matter ______ as it heats, then cools and slowly _______The result – ___________, a circular flow of matter that is very slow, but has important effects!
24Living on Oceanic Crust Most oceanic crust is covered with _________But many islands and the surface of some continents are made of oceanic crust_________ ________________________________ __________ (Idaho, Washington, Oregon)Oceanic crust soil is not as ________ because of large amounts of _______ and ____________Can be used to grow _________, _________, and ____________ or to graze ____________
26Graphing Activity Temperature Changes in then Earth Each student should complete the graphing activity using the data and the graph paper that I give out.If it is not completed in class, it must be done for homework.
29Section 2 Studying the Earth’s Interior Objectives:Identify two types of seismic wavesDescribe the movement of seismic wavesExplain how earth scientists make inferences about the earth’s coreInfer the characteristics of an object through indirect observation
30Skills Warm-up Boiling Over: Without removing the cover from a pot cooking on the stove, how could you determine what was cooking inside?How might your method of determining the pot’s contents be similar to the way scientists determine what is inside of the earth?
31How do we know it’s hot in there? Studying the EarthHow do we know that some parts are liquid and some are solid?How do we know it’s hot in there?How do we know what the chemical makeup is?
32Studying the EarthThe interior of the earth _______ be observed _________Deepest mine is ___ ____ _______Deepest hole ever bored into the crust went down only ________ – still far from the mantleEarth’s _________ does provide some clues________ _______(magma) from volcanoes is evidence for high temperatures inside the earthBut most knowledge has come from ________ ___________ of how _______ _________from earthquakes travel
33Shock Waves You have all probably experienced shock waves Have ever hit a baseball or softball with a bat?The vibrations or shock waves travel through the bat to your handsShock waves can also travel through the _______
34Seismic Waves____________ – sudden movements in the crust that can cause shockwaves________ _____– shock waves from an earthquakecan pass from one side of the Earth to the other__________ – instrument that detects seismic waves.Located all over Earth’s surfaceScientists gain valuable information about the interior of earth by comparing the ________ and ________ _______of waves
36The two types most useful for studying the Earth’s interior are: Types of Seismic WavesThe two types most useful for studying the Earth’s interior are:____ _______ travel in a _______________ movement of rock particles. Particles are squeezed together, then pulled apart.____ _______ travel in an ______________ movement of rock particles.S waves cannot travel through __________
38Speed and Bending of Waves _______ at which waves travel depends partly on the ________ of the rock it travels throughThe higher the density, the ________ the speedAs a wave passes through the Earth and encounters rock types with different densities, its speed __________If a wave passes through rock layers at a slight _______, a change in speed can cause it to change _____________
39Speed and Bending of Waves Most seismic waves travel in a ________ path through the Earth. This curving is called _________When a wave passes into a rock of a different ________, its path may ______ sharply
40Inferring from Seismic Waves With knowledge of how seismic waves travel, scientists have:Located the _________ between earth’s ________Inferred the ________/_________ __________ of layers
41Andrija Mohorovicic Croatian scientist In 1909 he discovered the boundary between the earth’s ______ and _________
42The Moho_________ ___________– “Moho”, the boundary between the crust and the mantle.At a depth of between ____and ____km below the surface, seismic waves suddenly ______ _____At this depth, rocks became much more ______, and probably of a different ________ ________
44The CoreWhen an earthquake occurs, it sends seismic waves in ____ _______P and S waves are detected by ______________At a certain distance away from where the earthquake occurs starts a zone in which ____ _________can be detectedCalled the _________ _______ – caused by the Earth’s ________
45The CoreNote that __________ __________ from the earthquake, only ____ ________ are detected. What does this tell you about the core?It suggests that at least part of the core is _______ since no ____ ________ are detectedThe size of the earth’s core can be calculated from the size of the _________ ________
47Answer the following questions: Where do the seismic waves from an earthquake go?What happens as P waves strike the core? Why?Which waves cross the core?Which waves are detected in the shadow zone?What can be used to calculate the size of the core?