| A | B |
|---|
| Asthenosphere | The bottom layer of the earth's mantle that lies beneath the lithosphere and consists of several hundred kilometers of deformable rock |
| convergent boundary | a plate boundary where plates are colliding and coming together, one or both plates fold, tilt and lift to form mountains |
| Crater | A bowl-shaped opening at the top of a volcano |
| crust | the thinnest, outermost layer of Earth; made up of rocky material |
| Divergent Boundary | Boundary between two plates moving away from each other |
| Earthquakes | Sudden movements of Earth's crust followed by a series of aftershocks |
| epicenter | point on Earth's surface directly above the location of initial plate boundary movement |
| Fault Line | Line determined by the intersection of a geological fault and the earth's surface |
| focus | location where earthquake movement first occurs |
| fossils | remains of once living organisms preserved in layers of sediment |
| Hot Spot | A constant stream of magma, one of which formed Hawaii |
| inner core | the hottest, most dense layer of Earth composed of mostly iron; located at the center |
| Lava | Rock that is in its molten form (as magma) issues from volcanos |
| Lithosphere | The solid part of the earth consisting of the crust and outer mantle |
| magma | molten rock that exists under the Earth's surface |
| Mantle | thickest layer, divided into two parts, upper mantle - solid hot rock layer and lower mantle - solid rock layer that flow like a liquid |
| mid-ocean ridge | mountain range that runs continuously around Earth on the seafloor with a rift valley in between; formed when magma is forced upward and cracks the crust apart; a source for new rock |
| Normal Fault | An inclined fault in which the hanging wall slips downward relative to the footwall |
| outer core | the liquid part of the core, located below the mesophere and above the inner core |
| plate boundary | plates meet at the edges of techtonic plate |
| plate tectonics | a system of plates made up of crust that move around the surface of Earth |
| plates | pieces of the lithophere that are composed of a rigid layer of the uppermost mantle and a layer of oceanic or continental crust, or both |
| Richter Scale | A logarithmic scale of 1 to 10 used to express the energy released by an earthquake |
| Rift Zone | Deep cracks between tectonic plates that are pulling apart and form new crust |
| seafloor spreading | pulling apart of plate boundaries under the ocean floor |
| seismic wave | wave produced by energy that is released when rock moves at plate boundaries |
| seismograph | records seismic waves- any movement in earth's crust |
| Shield volcanoes | gentle slopes, made of almost all lava, eruptions are calm, Hawaii |
| volcanoes | found in such areas as faults, plate boundaries ans hot spots - hot lava and gases can be pushed out of a volcano |
| destructive | When plates move and earthquakes happen this is this type of force that can cause damage to buildings, as well as landslides and tsunamis. |
| constructive | When mountains and volcanoes are created when lava cools into rock this is this type of force. |
| Spreading plate boundaries | When two plates move apart from one another…causing a low area/rift valley |
| Sliding plate boundaries | When two plates slide past each other in opposite directions… some get hooked together, the jerk apart causing an earthquake |
| faults | earthquakes occur most often at these cracks along plate boundaries |
| Colliding plate boundaries | Volcanos form near colliding plates, magma can forced out of the weak spots in the crust (a vent or a hole) |
| Core | The center of the Earth |
