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Historical Geology
plate tectonics
Question | Answer |
---|---|
What is plate tectonics? | a theory that describes the formation, movements, and interactions of these plates |
What is a mid ocean ridge? | a long chain of volcanic mountains on the ocean floor with a deep central boundary |
What are the 3 main types of plate boundaries? | divergent,convergent, and transform |
Divergent boundaries | a boundary between two lithosphere plates that are moving apart aka spreading centers |
What forms under water ridges? | divergent boundaries |
Mid Atlantic ridge | divergent |
Does divergent boundaries create new crust? | yes |
Convergent boundaries | a boundary where two plates are moving near each other or converging |
What are two broad classifications for convergent boundaries? | subduction boundaries and collision boundaries |
Does convergent boundaries create new crust? | no it destroys crust |
What does convergent boundaries form? | volcanoes, deep sea trenches, fault lines, islands |
What is a subduction boundary? | when a oceanic plate plunges beneath another plate |
True or False: subduction boundaries occur at the convergence of two oceanic plates or at the convergence of a oceanic plate and continental | True |
What does subduction form? | deep sea trenches |
What does collision boundaries for? | mountain ranges |
When two continent plates converge and collide what is it called? | collision boundary |
Transform boundary | a boundary between two plates that slide past each other |
Earthquakes are caused by? | transform boundaries |
What were the man gases of early earth? | carbon dioxide,ammonia, methane ,water vapor |
What was early water mainly like? | hot volcanoes everywhere with no oxygen |
what was the first big thing to help earth to get where it is | earth cooled |