Question | Answer |
infer | make an educated guess what each layer is made of |
inner core | the very center of the earth |
outer core | layer of liquid metals that surrounds the inner core |
mantle | earths thickest layer that surrounds the outer core |
crust | outer most layer of the earth |
continental crust | continents and majot islands |
oceanic crust | all the ocean floors |
lithosphere | earths crust and the very top of the mantle |
asthenosphere | a layer of hotter, softer rock in the upper mantle |
tectonic plates | large and small slabs |
continental drift | the hypothesis that earths contents move on the earths surface |
pangaea | supercontinent made from the continents joined together |
the theory of plate tectonics | a theory stating that the earths lithosphere is broken into large moving pieces which carry both continental and oceanic crust |
mid-oceab ridges | huge underwater mountains ranges |
sea-floor spreading | molten rock rised through cracks in the oceanic crust. it then cools to form new oceanic crust. the old crust is pulled away to make room for new material |
trenches | deep canyons- in the sea floor |
convection | energy transfer by the movement of a material |
convection current | motion that transfers hear energy in the material |
slab pull | occurs where gravity pulls the edge of a cool, dense plate into the asthenosphere |
ridge push | occurs when material from a mid-ocean ridge slides downhill from the ridge |