Plate tectonics
About this set
Created by:
tfreeman14 on April 5, 2011
Subjects:
Description:
Please add terms!
Log in to favorite or report as inappropriate.
Order by
33 terms
Terms | Definitions |
|---|---|
 plate | a solid section of the Earth's lithosphere- 20 plates move relative to one another atop the asthenosphere |
| convection current | circular motion of material due to heating and cooling responsible for the movement of the plates |
| lithosphere | crust very top of mantle plates |
| asthenosphere | what plates float on top of - mantle |
| Alfred Wegener | proposed that the continents were once joined together in a single land mass (called Pangea) in 1915 |
| Pangea | 200- 250 million years ago, it a was a single land mass- means all land in greek |
| Evidence for Pangaea | 1. Continents fit together (puzzle)- Africa and South America. 2. Fossils of plants and animals of same species were found on different continents 3. Mountain Ranges -correlations 4. coal was found where it should not have been able to form |
| continental shelves | continental edges underwater |
| Mesosaurus | freshwater reptile whose fossil provided evidence for Pangea |
| Glossopteris | a fern fossil, provided evidence for Pangea |
| Laurasia | Northern part of Pangaea |
| Gondwana | southern section of Pangea |
| Tethy's Sea | sea in Pangea between the northern and southern parts |
| Panthalassa | The single, large ocean that covered Earth's surface during the time the supercontinent Pangaea existed |
| Harry Hes | proposed seafloor spreading in 1962 |
| Iceland | the only place where the midatlantic ridge crossed land |
| Paleomagnetism | the study of changes in Earth's magnetic field, as shown by patterns of magnetism in rocks that have formed over time remnant magnetism in rock bodies |
| Vine and Matthews | the two people that came up with the magnetic discovery of paleomagnetism |
| Hot spots | not associated with plate boundaries- a plume of magma that rises towards the surface of the earth usually in the center of the plate, causes a volcanoe- plate moves relative to ________ |
| Seafloor spreading | the mechanism responsible for producing the new seafloor between two diverging plates |
| convergent plate boundary | where plates move together causing one of the slabs to be consumed into the mantle as it descends beneath an overriding plate. |
| normal polarity | when rocks exhibit the same magnetism as the present magnetic feild |
| divergent plate boundaries | the type of plate boundary where plates move apart, resulting in the upwelling of material from the mantle examples rift valley, mid Atlantic ridge |
| oceanic crust | crust formed from magma deep in the mantle DENSE |
| oceanic and continental | subduction, oceanic slides under, pushing continental upward, forms Mountain ranges (example: Andes) - site of volcanoes and earthquakes (name the plates) |
| continental and continental | overriding of one plate, formation of mountain ranges examples Himalayas |
| Oceanic and oceanic | forms an island arc ex; Japanese Islands, sites of volcanoes and earth quakes |
| Caledonia Mountains | Mt. range formed at the same time as Appalachians |
| 500,000 years | how often do the magnetic pulls flip flop |
| North American and Eurasian | two plates moving apart at the midatlantic ridge at iceland |
| deep ocean trench | fracture in subduction zone largest is Marianas trench |
| Transform Boundary | fault zones Ex San Andres fault site of earthquakes |
| Curie point | The temperature above which a material loses its magnetization. |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.
Set Champions
Scatter Champion
21.1 secs by iwilliams14
Space Race Champion
79,760 points by corachen14
Completed “Learn” mode
jgregory14 , nmcarthur14 , ftang14 , ccoffin14 , RSmith14 , tvalle-hoag14 , abarrett14 , jjacobs14 , mhoey14 , corachen14 , mwaddoups14 , camveidenheimer , sma14 , tfreeman14 , cbalboni14 (See all 24)