| A | B |
|---|
| mountain | a topographic elevation of more than 300 m (1000 feet) |
| range | a small group of similar mountains |
| chain, system | a larger group of mountains with broad similarities |
| belt | continental/global scale group of mountains |
| volcanism | tectonic activity involving magma at the surface |
| ocean-ocean convergent margin | plate margin between two ocean plates with compressional stress |
| volcanic island arc | mountain range formed at an ocean/ocean convergent margin |
| ocean-continent convergent margin | plate margin between an ocean plate and a continental plate with compressional stress |
| volcanic/magmatic arc | mountain range formed at an ocean/continental convergent margin |
| oceanic divergent margin | plate margin between two ocean plates with tensional stress |
| mid-ocean ridge | mountain range formed at an ocean/ocean divergent margin |
| mantle plume | a rising column of earth material within the mantle |
| hot spot | crust location over a mantle plume |
| deformation | tectonic activity involving the folding or faulting of rocks |
| folding | plastic deformation of rocks, the "bending" of rocks |
| faulting | rupture deformation of rocks, the "breaking" of rocks |
| thrust-block mountains | older term for mountains formed by compressional thrust faulting |
| continent-continent convergent margin | plate margin between two continental plates with compressional stress |
| fold/thrust belt | mountain range formed at a continental/continental convergent margin |
| fault-block mountains | older term for mountains formed by tensional stress |
| continental divergent margin | plate margin between two continental plates with tenional stress |
| rifting | tectonic activity (faulting) continental divergent margin |
| up-warped mountains | older term for mountains formed by vertical stresses |
| eruptive complex | igneous landscape feature composed of extrusive rocks |
| extrusion | eruption of magma as "quiet" lava flows |
| ejection | eruption of magma as explosive blast of tephra into the atmosphere |
| tephra | any type of pyroclastic material ejected into the atmosphere |
| tephra plume | a cloud of tephra erupting from a vent |
| vent eruption | a volcanic eruption (extrusion or ejection) from a relatively small opening in the crust |
| volcanic cone | the eruption feature that forms around a vent |
| crater | conical depression at the summit of a volcano |
| vent | the opening the crust from which magma erupts |
| shield volcano | vent eruption feature, volcano formed by flows |
| composite cone, stratovolcano | vent eruption feature, volcano formed by flows and pyroclastics |
| cinder cone | vent eruption feature, volcano formed by pyroclastics |
| lava plug, plug dome, rhyolite plug | vent eruption feature, extrusion mass filling the vent |
| lava dome | vent eruption feature, a shield-shaped volcanic feature |
| splatter cone | vent eruption feature, formed by "splatters" of magma |
| fumarole | vent eruption feature in which volcanic gases escape into the atmosphere |
| mud volcano, mudpot | vent eruption feature, in which heated groundwater mixes with the soil/regolith |
| geyser | vent eruption feature in which steam from heated groundwater erupts |
| fissure eruption | magma eruption from a large crustal fracture |
| flood basalts, plateau basalts | extrusive rocks that form around a fissure eruption |
| lava plateau | the large, flat-topped landscape feature that forms during a fissure eruption |
| caldera | a large basin-shaped depression that forms when a volcano collapses after a massive ejection of magma |
| deformation | tectonic activity involving the folding or faulting of rocks |
| dipslip fault | faulting with vertical offsets |
| normal fault | tensional dipslip fault with footwall up and hanging wall down |
| crustal lengthening | tectonic result of tensional stress |
| monocline | a vertical uplift feature, a single limb structure where dip increases within uniform tilted layers |
| hanging wall | that side of a dipslip fault the "leans" over the opposite side |
| footwall | that side of a dipslip fault the "porjects" under the opposite side |
| reverse fault | compressional dipslip fault with footwall down and hanging wall up |
| thrust fault | a compressional dipslip fault, a low-angle reverse fault |
| crustal shortening | tectonic result of compressional stress |
| anticline | a compressional fold that is convex upward |
| syncline | a compressional fold that is convex upward |
| fold limb | a compressional fold that is concave upward |
| symmetric fold | a fold in which both limbs have similar dip |
| asymmetric fold | a fold in which the limbs have different dip |
| overturned fold | a fold in which one of the limbs is folded past vertical |
| recumbent fold | a reclining fold in which the overturned limb is nearly horizontal |
| dome | a large, circular anticline |
| basin | a large, circular syncline |
| strike slip fault | a shear stress fault with lateral slip |
| right-lateral | strike slip fault with right-handed offset |
| left-lateral | strike slip fault with left-handed offset |
