Term
|
Definition
-lava flows
-lava bomb
-pyroclastic flow
-ash fall
-poisonous gases
-lahars |
|
|
Term
| how do the volcanic hazards flow |
|
Definition
-lava flows travel downhill
-lahars & pyroclastic flows follow river channels
-ash travels in the direction of the wind |
|
|
Term
| why do people live near volcanoes and what is the catch 22 |
|
Definition
| they live near them because they provide rich topsoil for vegetation but the catch 22 is that it can destroy their livelihood |
|
|
Term
| what things are monitored on volcanoes |
|
Definition
-volcanic gases
-plume monitoring
-freshwater acidity |
|
|
Term
| what things are looked at for potential volcanic eruptions |
|
Definition
-seismic activity
-ground elevation
-gas output
-water acidity (ground/fresh) |
|
|
Term
| what are the effects on the climate from volcanic eruptions |
|
Definition
-global cooling: ash and sulfur reflect suns rays away and sulfuric acid attacks the ozone
-higher acid rain concentration
-global warming: increased CO2 traps infared rays and acts as a blanket |
|
|
Term
| what is mass wasting and how does it vary |
|
Definition
-it is a large volume of material moving down a slope all at once
-it varies on water content and rate of motion |
|
|
Term
| what are the different types of mass wasting |
|
Definition
-fall: rapid movement of material
-slides: semi solid mass moves along bottom
-flows: fluid moves down slopes rapidly
-creep: slow movement downhill
-subsidence: determined by underlying material |
|
|
Term
| what controls slope stability #1 |
|
Definition
| -slope angle: angle of repose is the steepest possible angle that loose material can sustain. Resisting mass must be greater than driving mass or failure with occur |
|
|
Term
|
Definition
-material
-water content
-angle of layers
-vegetation
-climate |
|
|
Term
| what is the factor of safety |
|
Definition
-resisting fores/driving forces
-if +1 slope is safe, if not its unstable |
|
|
Term
| what triggers mass wasting |
|
Definition
-an earthquake
-volcanic eruptions
-heavy rainfall |
|
|
Term
| how to prevent the effects of mass wasting #1 |
|
Definition
-reduce the slope: add more mass to resisting force
-benching
-water reduction
*drainage control (rechannel canals)
*cover the surface
*drain system |
|
|
Term
| prevent mass wasting effects #2 |
|
Definition
-water removal wells
-slope support
*cement walls
*chicken wire baskets
*rock bolts
*shotcrete
*netting
*rock scaling |
|
|
Term
|
Definition
| -through the pore spaces present in rocks |
|
|
Term
| what is porosity and what material works best? |
|
Definition
-the space between the grains in a rock or sediment
-sediment works best |
|
|
Term
|
Definition
| the ability for fluid to travel between pore spaces...the better connected the pore the better |
|
|
Term
|
Definition
-aquifer: good porosity and permeability (sand, gravel, sandstone & limestone)
-aquiclude: poor porosity/permeability (clay, shale, quartzite)
* aquiclude with good porosity but poor permeability is possible |
|
|
Term
| how does gw flow and what influences the flow |
|
Definition
-flows downhill
-influenced by slope of hill and material
permeability |
|
|
Term
|
Definition
-rainfall/snow melt
-pump out of ground, will recharge
*overpumping causes cone of depression |
|
|
Term
| what are the benefits of a confined aquifer |
|
Definition
-safe from contamination
-constant supply of water
-can create artesian well |
|
|
Term
| what does salt water do to gw and who is affected |
|
Definition
-ocean regions are affected
-salt water is more dense so freshwater floats
-overpumping causes the two to mix |
|
|
Term
| what is the geologic history of phx |
|
Definition
-basin and range led to normal fault blocks
-sediments filled in, great for aquifers |
|
|
Term
| what are earth fissure characteristics |
|
Definition
-gw overpumped, water space filled w/ settling sediments
-this causes elevation drop (subsidence)
-differential settling causes tension cracks
-cracks grow due to water erosion
-once space is filled with sediment it can never be refilled w/ water |
|
|
Term
| what are some earth fissure hazards |
|
Definition
| -unstable foundation for homes and roads |
|
|
Term
|
Definition
-earth fissures
-overpumping of oil
-over mining of ore material
-sinkholes |
|
|
Term
|
Definition
-made of carbonate material
-water reacts w/ limestone to form rock eating acid
-in humid climates
-creates caverns (fl and KY) |
|
|
Term
|
Definition
-fecal coliform bacteria (e. coli)
-fertilizers w/ nitrogen & phosphorous
-oil/gas
-hazardous materials (chemicals, metals)
-pharmaceuticals (hormones, antibiotics, antidepressants, caffeine) |
|
|
Term
| what are the sources of contamination and what is the problem with finding it out |
|
Definition
-point source (1 location)
-non-point source (many regions)
- can be difficult to figure out but you have to in order to clean the water |
|
|
Term
| what are some ways to treat the contaminated gw |
|
Definition
-extraction wells
-vapor extraction
-bioremediation
-permeable treatment bed |
|
|
Term
| what are some safe ways to dispose of the contaminated gw |
|
Definition
-containments (landfills, but leaks)
*location
*proper lining
*allow for appropriate decomp.
-injection wells |
|
|
Term
| what are the pros of yucca mountain |
|
Definition
-made of fractured volcanic rock, good aquiclude
-dry climate
-containers designed for 10,000 yrs
-safer than now |
|
|
Term
| what are the cons for yucca mountain |
|
Definition
-cinder cones
-near active eq. fault
-part of potential Las Vegas aquifer
-max. radiation output in 100,000yrs
-transport danger |
|
|
Term
| what are some river basics |
|
Definition
-travel from high elevation to low
-w/ large gradients it moves faster
-w/ small gradients, it moves slower
-whole drainage system in the watershed for a given river |
|
|
Term
| what are the high elevation elements |
|
Definition
-steep
-deeply cut channels
-straight flowing |
|
|
Term
| what are some low elevation elements |
|
Definition
-flatter, wider channels
-meandering directions
-levees and floodplains |
|
|
Term
| what is erosion rates dependent on |
|
Definition
-discharge: volume of water moving at one time (D=WxDxV=cubic ft/sec)
-sediment load: less sed. greater rate of erosion |
|
|
Term
| what are the types of floods |
|
Definition
-flash: high elevations, intense thunderstorms, discharge increase fast
-regional: lower elevations, long & drawn out rainfall |
|
|
Term
| what is flood recurrence dependent on |
|
Definition
-occur at regular intervals
-occurs as a % of likelihood to occur in any given yr
-100yr flood= 1% chance of this magnitude occurring in a given year
-based on discharge |
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