Plate Tectonics

6. - When subducting plates contain continental material, two continents collide
8. – Deep faulted structures found along the axes of divergent plate boundaries
14. – form as volcanoes emerge from the sea
16. - At a______ ______ ______, plates grind past each other without destroying the lithosphere. (3 words)
19. – The rigid outer part of the earth, consisting of the crust and upper mantle
20. – Form in part by volcanic activity caused by the subduction of oceanic lithosphere beneath a continent
21. - Fossil evidence for continental drift includes several fossil organisms found on different _______.
22. – Where two plates move together
23. – Margins where two plates grind past each other without the production or destruction of the lithosphere
24. - Denser oceanic slab sinks into the asthenosphere

1. – Produces new oceanic lithosphere
2. – One oceanic plate is forced down into the mantle beneath a second plate
3. – The continents had once been joined to form a single supercontinent
4. – Early aquatic relative of reptiles, found as fossils from the Early Permian Period in South Africa and South America
5. – Extinct genus of about seven species of medium-sized heavily built animals that lived from the middle of the Permian Period until early in the Triassic Period
7. – Genus of extinct advanced therapsids (mammals and their relatives) found as fossils in South Africa and South America
9. – Continuous elevated zones on the floor of all major ocean basins
10. – The supercontinent that began to break apart 200 million years ago and form the present landmasses
11. – Genus of fossilized woody plants known from rocks that have been dated to the Permian and Triassic periods deposited on the southern supercontinent of Gondwana
12. – Numerous rigid sections of the lithosphere that move as a unit over the material of the asthenosphere
13. – The upper layer of the earth's mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur
15. – When spreading centers develop within a continent, the landmass may split into two or more smaller segments
17. – The place where two plates move apart
18. - Two oceanic slabs converge and one descends beneath the other