Download presentation
Presentation is loading. Please wait.
1
Plate Tectonics - PANGAEA http://www.middleschoolscience.comhttp://www.middleschoolscience.com 2009
2
Evidence of Pangea
8
Continental Drift http://members.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml Alfred Wegener 1900’s Continents were once a single land mass that drifted apart. Theory is called continental drift. Fossils of the same plants and animals are found on different continents Called this supercontinent Pangaea, Greek for “all Earth” 250 Million years ago Split again – Laurasia & Gondwana 180 million years ago
9
Tectonic Plates- major and minor
10
How Plates Move- convection currents in the mantle causes hot magma to rise and sinks as it cools. This movement results in the movement of the lithosphere/crust. http://pubs.usgs.gov/gip/dynamic/unanswered.html
11
Earth’s Layers The Earth's rocky outer crust solidified billions of years ago, soon after the Earth formed. This crust is not a solid shell; it is broken up into huge, thick plates that drift atop the soft, underlying mantle.
12
The Crust Outermost layer 5 – 100 km thick Made of Oxygen, Silicon, Aluminum
13
The Mantle Layer of Earth between the crust and the core Contains most of the Earth’s mass Has more magnesium and less aluminum and silicon than the crust Is denser than the crust
14
The Core Below the mantle and to the center of the Earth Believed to be mostly Iron, smaller amounts of Nickel, almost no Oxygen, Silicon, Aluminum, or Magnesium
15
Plate Tectonics “tektonikos” means “builder” in GREEK Pieces of the lithosphere that move around Float on top of mantle’s asthenosphere similar to ice cubes in a bowl of water Each plate has a name Fit together like jigsaw puzzles
16
Sea Floor Spreading Mid Ocean Ridges – underwater mountain chains that run through the Earth’s Basins Magma rises to the surface and solidifies and new crust forms Older Crust is pushed farther away from the ridge
17
Different Types of Boundaries http://pubs.usgs.gov/gip/dynamic/understanding.html
18
Divergent Boundary – Arabian and African Plates
19
Convergent Boundary – Indian and Eurasian Plates
20
Convergent Boundary – Oceanic & Continental (denser oceanic crust will dive under the less dense continental crust, creating volcanoes or trenches http://pubs.usgs.gov/gip/dynamic/understanding.htmlhttp://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.comhttp://www.geology.com
21
Convergent Boundary – Oceanic & Oceanic (one will dive under the other due to density. This may result in the formation of a trench or volcanoes. http://pubs.usgs.gov/gip/dynamic/understanding.htmlhttp://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.comhttp://www.geology.com
22
Convergent Boundaries – Continental & continental crust create mountains http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.comhttp://www.geology.com
23
Transform Boundary – when 2 plates slide past each other due to friction, usually resulting in earthquakes. www.geology.com
24
Review Name the 3 main layers of the Earth What is a tectonic plate? What was Pangea? What is Sea-Floor spreading? Name the three different types of plate boundaries and one location on Earth for each one
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.