| A | B |
|---|
| Mantle | thickest layer of earth made of hot rock |
| outer core | layer of earth made of liquid metal |
| inner core | layer of earth made of solid metal |
| crust | layer of earth where sudden shifts cause earthquakes |
| heat transfer | movement of energy from warmer object to cooler one |
| radiation | transfer of heat through open space |
| convection | transfer of heat through direct contact of objects |
| conduction | transfer of heat by movement of heated fluid |
| convection currents | flow that transfers heat through a fluid |
| asthenosphere | where convection currents are located in the mantle |
| Pangaea | Alfred Wegener's super-continent |
| mid-ocean ridge | where molten material rises from the mantle and erupts |
| Sea-Floor Spreading | Harry Hess's radical idea about the ocean floor |
| plates | seperate sections of the lithosphere |
| faults | breaks in Earth's crust where rocks slip by one another |
| transform boundary | two plates slip by each other in opposite directions |
| divergent boundary | two plates move apart, or diverge |
| convergent boundary | two plates move towards each other, or converge |
| rift valley | deep valley that forms along a divergent boundary on land |
| earthquake | shaking and trembling from rocks moving beneath Earth's crust |
| seismic waves | vibrations that travel through Earth carrying energy released during an earthquake |
| aftershock | earthquake that follows a much larger earthquake |
| tsunami | large wave formed by water displaced by an earthquake |
| magma | what lava is called before it reaches Earth's surface |
| tension | stress that pulls on the crust, stretching rock so that it becomes thinner in the middle |
| compression | stress that squeezes rock until it folds or breaks |
| fault | break in the Earth's crust where slabs of crust slip past each other |
| three main types of faults | strike-slip, normal, and reverse |
| types of stress in rock | shearing, tension, and compression |
| deformation | any change in volume or shape of the Earth's crust such as bending, stretching, breaking, tilting, folding and sliding |
| shearing | stress that pushes rock in two opposite directions |
| strike-slip fault | rocks on either side of the fault slip past each other in opposite directions |
| normal fault | tension forces cause the angled break in crust so that the footwall is above and the hanging wall is below |
| reverse fault | compression forces cause the angled break in crust so that the footwall is below and the hanging wall is above |
| friction | the force that opposes the notion of one surface as it moves across another |
| fault movement | over millions of years movement in the breaks of the Earth's crust can change a flat plain into a towering mountain range |
| fault-block mountain | tension forces create parallel normal faults where the hanging walls slip downward and leave a block of rock in the middle that pushes upward |
| folds | bends in the rocks that form when compression shortens or thickens part of the Earth's crust |
| examples of mountains formed by folds | Himilayas in Asia and the Alps in Europe |
| mountains formed by folds | when plate movement causes the rock to fold - such plate collisions can lead to earthquakes |
| examples of fault-block mountains | Great Basin from Salt Lake City, Utah and Los Angeles, California has many fault-block mountain ranges |
| anticline | a fold in the rock that bends upward in an arch |
| syncline | a fold in the rock that bends downward to form a bowl |
| examples of anticlines | Black Hills of South Dakota |
| examples of synclines | Illinois basin |
| plateaus | large area of flat land elevated high above sea level when vertical faults push up a large, flat block of land |
| examples of plateaus | "Four Corners" region of Arizona, Utah, Colorado, and New Mexico |
| focus | point beneath the Earth's surface where rock that is under stress breaks, triggering an earthquake |
