2.  “Weak sphere”  Layer that is involved in mantle convection

3.  Asthenosphere

4.  Line where it is hot enough below to flow and is cool and rigid above

5.  Boundary between lithosphere and asthenosphere

6.  Thick, less dense, and older

7.  Continental crust

8.  Boundary where plates are moving toward one another

9.  Convergent Boundary

10.  Example of a transform boundary

11.  San Andreas Fault

12.  Collision zone where subduction is active, earthquakes and volcanoes are possible

13.  Subduction  Continent-Oceanic collision

14.  Large forces build up within the lithosphere, forces become greater than the strength of the rock thus fracturing.

15.  Fault

16.  A place where molten rock, solid fragments and gases erupt at the Earth’s surface

17.  Volcanoes

18.  Mild Eruption

19.  Magma with low gas content

20.  Magma pockets in the mantle that do not move. Ocean plates move. Occur far from plate boundaries.

21.  Hot spot volcano

22.  Formed when 2 continental crusts collided. Still forming. No subduction.

23.  Himalayan mountains

24.  Rigid outer portion of the Earth. Composed of crust and the outer part of the mantle.

25.  Lithosphere

26.  Thin, more dense, and younger.

27.  Oceanic crust

28.  Boundary where plates are moving away from each other

29.  Divergent Boundary

30.  Boundary where plates are sliding past one another (very slow).

31.  Transform Boundary

32.  Area where plates are consumed (melted and recycled); one plate dives down underneath the other into the mantle.

33.  Subduction

34.  Collision zone where there is no subduction and mountains are formed.

35.  Continent-continent collision

36.  Fracture in the Earth’s surface

37.  Fault

38.  Explosive eruption

39.  Magma with high gas content

40.  Volcanic rock found along the Mid-Ocean Ridges

41.  Basalt

42.  Pacific Ocean rimmed with subduction zones. Earthquakes and volcanoes are common.

43.  Ring of fire

44.  A continuous mountain range extending throughout the ocean. It is seismically active and often has a rift valley. Divergent plate boundaries. Site of sea-floor spreading.

45.  Mid-ocean ridge