1 / 31

Earth’s Interior

Earth’s Interior. Direct evidence – rock samples from up to 12km deep 2. Indirect evidence – seismic waves (waves that travel through the earth during earthquakes). wps.prenhall.com. Temperature and Pressure. Temperature Deeper you go the warmer it is

raven
Download Presentation

Earth’s Interior

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Earth’s Interior Direct evidence – rock samples from up to 12km deep 2. Indirect evidence – seismic waves (waves that travel through the earth during earthquakes) wps.prenhall.com

  2. Temperature and Pressure Temperature • Deeper you go the warmer it is • After 20 meters, every 40 meters you descend the temperature rises 1 degree Celsius • High temperature results from the formation of the planets and radioactive substances releasing energy Pressure • The deeper you go, the higher or greater the pressure

  3. Layers of the Earth myschoolhouse.com

  4. Layers of the Earth • Crust: layer of solid rock that includes both dry land and ocean floor a) oceanic crust – crust beneath the ocean, made of basalt rock http://volcanoes.usgs.gov/images/pglossary/basalt.php b) continental crust – the crust that forms the continents (land), made of granite nwnature.net beg.utexas.edu

  5. Layers of the Earth • Mantle: below the crust, very hot and solid, 3,000 km thick a) lithosphere: uppermost mantle and crust, pushed together, 100km thick b) asthenosphere: soft layer of the mantle (it can bend like plastic) but is still solid, the lithosphere floats on top of this layer, 2,767km thick c) lower mantle: beneath the asthenosphere, solid layer that extends to the core

  6. Layers of the Earth 3. Core – two parts made of iron and nickel a) outer core: layer of molten metal that surrounds the inner core, this layer is liquid b) inner core: solid metal due to extreme pressure. - The movement in the core creates Earth’s magnetic field

  7. Convection and the Mantle Types of Heat Transfer • Radiation: transfer of energy through space, no direct contact needed. Example: sun  blacktop or heat from fire • Conduction: heat transfer within a material or between materials that are touching (soup spoon in soup pot) • Convection: heat transfer by the movement of currents within a fluid (bounce off one another and heat up, example: teapot). - caused by differences in temperature and density within a fluid

  8. Density = mass/volume Density: amount of mass in a given volume of a substance. • as gas or liquid is heated, the particles move faster and take up more space, decreasing it’s density • as a gas cools, the particles slow and settle closer, increasing it’s density

  9. Convection currents: the flow that transfers heat within a fluid • Gravity and density put these currents in motion * Convection currents occur in the mantle and outer core * physics.arizona.edu

  10. Continental Drift • It states: that all the continents were once joined together in a single landmass and have since drifted apart • Alfred Wegener responsible for this idea • When all continents were joined together it was called Pangaea • Wegener used evidence from land features, fossils, and climate change to prove this theory (it was NOT accepted) Land: used mountains and features on the continents Fossils: any trace of an ancient organism preserved in rock Climate change: as a continent moves toward the equator, it becomes warmer (coal was found in Antarctica)

  11. Sea-floor Spreading • Sea-floor spreads apart along both sides of a mid-ocean ridge as new crust is added • Ocean (sea) floor moves like a conveyor belt, carrying the continents along with them 123rf.com

  12. Mid-ocean ridge: a mountain chain at the bottom of the ocean where the new ocean is produced. - The new ocean floor forms when lava is erupted onto the ocean floor. http://geomaps.wr.usgs.gov/parks/animate/index.html

  13. Evidence of Sea-Floor spreadingHarry Hess’s theory • Molten material: tube shaped rocks from molten material hardening quickly • Magnetic stripes: pattern of magnetized stripes (iron in the rock), when rock cools • Drilling samples: rock samples farther away from mid-ocean ridge the older the rock was

  14. xtimeline.com

  15. Subduction and Trenches Deep ocean trench: deep underwater canyon that bends downward into the oceanic crust Subduction: when the ocean floor sinks beneath a deep ocean trench and back into the mantle

  16. How has this changed our oceans? • Pacific Ocean is shrinking because the deep ocean trenches are too big • Atlantic Ocean is getting bigger because it only has a few short trenches

  17. Plate Tectonics Plates: broken sections in the lithosphere that look like cracks Plate tectonics: pieces of Earth’s lithosphere are in slow, constant motion, driven by convection currents in the mantle • This theory explains the formation, movement, and subduction of Earth’s plates • As plates move, they collide, pull apart, or grind past one another

  18. Plate Boundaries Divergent boundary: place where 2 plates move apart. Example – Great Rift Valley or Grand Canyon • Occur along mid-ocean ridges • Forms a rift valley (deep valley on land) cotf.edu

  19. Convergent Boundary Definition: place where two plates come together or collide • The more dense (heavier) plate will sink below the other plate (subduction) • On land this creates mountain ranges cotf.edu

  20. Transform Boundary Definition: place where two plates slip past one another in opposite directions *Earthquakes occur here* gweaver.net

  21. Different Types of Boundaries http://pubs.usgs.gov/gip/dynamic/understanding.html

  22. Divergent Boundary – Arabian and African Plates Arabian Plate Red Sea African Plate

  23. Divergent Boundary – Iceland http://pubs.usgs.gov/gip/dynamic/understanding.html

  24. Divergent Boundary - Oceanic http://www.geology.com

  25. Divergent Boundary - Continental http://www.geology.com

  26. Convergent Boundary – Indian and Eurasian Plates Eurasian Plate Indian Plate

  27. Convergent Boundary – Oceanic & Continental http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com

  28. Convergent Boundary – Oceanic & Oceanic Note – plates are reversed http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com

  29. Convergent Boundaries - Continental http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com

  30. Transform Boundary – San Andreas Fault www.geology.com

  31. How to calculate plate movement Rate = Distance/Time Example: A plate takes 2 million years to move 156km. Calculate the rate at which the plate moved. 156km/2,000,000yrs = 7.8cm/year

More Related