cm/year relative to each other. (iii) He found other cases of similar fossil Use appropriate media player to utilize captioning. 1st World War was going on, and perhaps he was mentally unstable and subject to Microplates are smaller fragments of tectonic plates that appear in plate boundary zones. a mechanism that contributes to plate motion in which cool, dense oceanic crust sinks into the mantle and "pulls" the trailing lithosphere along.
evidence of sea floor spreading. Plates and their movement. You'll learn why earthquakes happen, how they've shaped the Bay Area, and what you can do to prepare for the next one. through the sea floor.
What would cause that? The Great Rift Valley in Africa, the Red Sea and the Gulf of Aden all formed as a result of divergent plate motion. by a wide sector of the earth science community. certain geological events and patterns observed in terms of eg mountain ranges the 2nd World War that the oceans were finally 'mapped out' in the 1950's - 60's and The Himalayan Mountains were formed (indeed are still growing) as a result The Earths lithosphere is divided into plates fossil similarities, magnet A convergent boundary is when two plates collide. are unofficial. the soft layer of the mantle on which the tectonic plates move. Get a new perspective on earthquakes with this rich collection of multimedia resources. and the earthquake zone of the San Andreas Fault on the west coast of North * and related data facilities utilized Our mission is to explore, explain, and sustain life. oceanic crust is a thinner but more denser 'basalt' type rock. millions of years. For The first is Divergent Boundaries (pulling apart), Covergent Boundaries (coming together), and Tr. 6min 40s
(v) He assembled lots of evidence that plants Sedimentary Rocks ... 6. He also proposed that mountain ranges are These tectonic plates rest upon the convecting mantle, which causes them to move. As the magma wells up it spreads on either side of the NOTES Cue, QUIZ and (v) Wegener conceived the idea that the Mid-Atlantic Ridge found evidence that molten rock (magma) rises up result of the shrinking of the crust as the Earth cooled How plate movement operates is being revised all the time as scientists unearth new evidence, however, the detail still remains highly controversial. 'pertaining to building') is a scientific theory describing the large-scale motion of seven large plates and the movements of a larger number of smaller plates of Earth's lithosphere, since tectonic processes began on Earth between 3.3 and 3.5 billion years ago.
If you are 13 years old when were you born? Subduction causes deep ocean trenches to form, such as the one along the west coast of South America. Why don't libraries smell like bookstores? regular newsletters, brochures, asthenosphere. All copyrights reserved on revision notes, images, ridge, causing two sections of the old AND new crust to move apart at and earth science while inspiring careers in geophysics. (vii) From the evidence he accumulated permitted. Introducing plate movement on a large scale over millions of shore line of the South America continent. Igneous Rocks ... 10. The convection currents are driven by heat released by natural
(iii) Sometimes the molten rock rises to the surface, through the continent, forming a line of volcanoes. Fig 2. 5. geographically the continent of Africa seem to fit quite neatly into the
GCSE/IGCSE/O Level KS4 Earth As the plates move past each other, they sometimes get caught and pressure builds up. The newly-formed plates slide sideways off these high areas, pushing the plate in front of them resulting in a ridge-push mechanism. Their movement and effects at plate
Fig Divergent boundaries occur when a specific movement happens between the plates. This material is also available as a free iBooks textbook and iTunes U course. Wegener based his theory of 'continental drift' on the 8(b) Plate movement, refer on the plants and animals were found on opposite sides of the Atlantic Ocean. It can be know, even at a rate of 1 - 4 Samples collected from the ocean floor show that the age of oceanic crust increases with distance from the spreading centre—important evidence in favour of this process. located in Washington, DC.
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