Term | Definition |
Classifying Mass Movement | Falls + Slides + Flows |
Triggering Mechanisms (Mass Movement) | Earthquakes, Volcanoes, Undercutting of toe, Human caused vibrations, saturation via water |
Mass Movement | Down slope movement of rock and soil under the force of gravity. |
Stream/River Base Level | Lowest point a stream can erode in its bed. |
Drainage Basin | Where streams converge. |
Divides | The separation of drainage basins by ridges and such. |
Drainage Patterns | Dendritic: Develops in valleys. Branching.
Parallel: forms on steep slopes. swift and straight.
Trellis: tributaries entering river at a ninety degree angle.
Radial: flowing into a central location. Volcanoes esp. |
Base flow | lowest discharge of any given river. |
Stream Discharge | Q=VA ---> width x distance x velocity |
Stream Erosion/Transport/Deposition | Erosion: hydraulic action, abrasion, corrosion
Transport: Bed load, suspended load, solution load
Deposition: Alluvial fans, deltas, natural levees |
Coastal processes | Waves, ocean currents, storms, tides |
Littoral current | Develops from waves hitting the shore at an angle. Travels parallel to the shoreline. |
Coastal landforms | Erosional: Stacks/arches, wave cut terraces, headlands,
Depositional: Baymouth bars, beaches, spits. |
Waves -- sets, rogue, tsunami | Rogue: spontaneous waves that occur far out in the sea
Wave sets: usually result from plate movement. Can also occur due to underwater mass wasting. |
Earth's Fresh water breakdown | 97.22 = ocean water. 2.78 = fresh water, of that 2.78, 77% is frozen, 22% underground, 1% in lakes. |
Alpine Glacier (Deposition) | Medial moraine: deposited debris/sediment formed at the point when two glaciers coalesce.
Lateral moraine: parallel debris deposition
Terminal moraine: deposited at the snout of a glacier |
Alpine Glacier (Erosion) | Striations (scratches on underlying bedrock tell the direction of glacier)
Cirque: formed at the head of a glacier.
Tarn: mountain lake formed in a cirque created by a glacier
Horn
Bergschrund: deep crevasse at the head of a glacier. |
Continental Glaciers (deposition) | Eskers: old stream beds
Kettle lakes: formed from separated ice blocks
Kames: essentially sand domes
erratics: large displaced rocks. |
Continental glaciers (erosional) | Drumlin: deposited till in an upside-down spoon shape. The downhill slope corresponds with the direction of the glacier
Roche Moutonnee: bedrock, movement of glacier corresponds to direction away from plucking. |
Extent of Wisconsin Glaciation | Covered New York, through southern tip of Illinois to Seattle. |
Laurentide and Cordilleran | Right side of rockies = Laurentide, Cordilleran = left side. |
Post-glacial rebound | Rise of landmass after depression from ice sheet/glaciers. Occurring in Scandinavia and Hudson Bay |
Pluvial Lakes | Once existed, now nonexistent lakes. Existed during most recent glaciation. (e.g. Area 51) |
Ice Age; Cause | One theory says the Earth goes through a cooling period every 100,000 because of change in its relative position to the Sun. |
Defining a Desert | An area that receives less than 10 in. of rainfall per year. |
The Four Deserts | Mojave, Great Basin, Sonoran, Chihuahuan |
Dist. of Deserts | Results from 3 predominant factorsl;
- Distance from moisture
- located on the "lee side" of a large mountain range
- located in sub tropical high pressure zone |
Aeolian (erosion) | Deflation - blowing away of loose particles. Creates desert pavement + blowout depression
Abrasion - produces pitted, grooved landforms. Also, yardangs.
Varnish - rapid evaporation after precip. |
Aeolian (transport) | Dust storm: especially find particles carried high in the atmosphere.
Sand storm: carried few metres off ground. Moves by saltation (aerodynamic lift) |
Aeolian (deposition) | - Ripples, formed at right angles.
Various dune shapes:
- barchan (parabolic) forms horns.
- longitudinal resulting from strong one-directional winds.
- star dunes (variable winds) |
Loess | Essentially fine sediment deposited after glaciation. Was picked up and deposited in areas like the Great Plains. REEEAL good for agriculture. |
Sahel | Location in Northern Africa where there exists a transition zone between rain forest and desert. |
Defining ecosystems | an area containing biotic + abiotic factors |
Two Abiotic Factors Affecting Dist. of Biomes | Temperature + Precipitation |
Arizona's Life Zones (C. Hart Merriam) | Lower Sonoran ---> Upper Sonoran (Pinyon-Juniper woodland, grassland) ----> Transition (ponderosa pine) --- > Canadian (mixed conifer) ---- > Hudsonian (Spruce fir + Subalpine conifer forest) --- > Arctic Alpine |
Neap & Spring Tides | Spring; when moon + sun are aligned. Causes higher tide
Neap: moon and Sun are at right angle from each other, results in lower tides. |