exam 3 Flashcards
contour map
a common and effective way to show how a measurement varies across an area
contour lines
drawn to connect known or interpreted points of equal value. connect points of equal elevation
contour interval
the difference in elevation represented by two successive contour lines
rules for contouringing
- contour lines never cross each other
- contour lines never split or merge
- honor all points in the construction of the map
- a contour line passes directly through a point only if its value is exactly that of the contour line
- observe the contour interval when deciding which contour lines to draw.
mineable acreage
limits will reduce the amount of mineable acreage. the total area you are able to mine on
mining ratio
the higher the ratio, the more costly the mining will be
depth limit
the cost of removing overburden rocks can become too expensive (thickness of rocks above coal seam) (250 ft)
minimum thickness limit
(20 ft) not enough coal = no profit
maximum sulfur limit
(2% sulfur) air pollution standards
stream encroachment limit
(4000 ft buffer zone) keeps streams from getting polluted
intensity
the amount of shaking and destruction of buildings or structures based on what humans feel or observe (modified mercalli scale)
modified mercalli scale (numbers)
higher numbers indicate that more shaking was felt by people in the area and more more damage to buildings or structures was observed
Mercalli scale
measures intensity on a scale from I to XII (1 - 12) based on the impact to humans and damages to buildings. does not need any equiptment
richter scale
measures magnitude on a logarithmic scale from 1 - 10. uses seismographs to measure the EQ’s. a measure of the energy released. (also known as local magnitude)
epicenter
the point on earths surface directly above the rupture
focus
point of rupture inside the earth directly below the epicenter
fault
a pre-existing fracture
seismic shock waves
sent by the rupture from the focus in all directions
seismograph
the principal tool used to investigate earthquakes
seismogram
an output where the wiggles produced by the seismic waves is recorded (the larger the earthquake the larger the wiggle)
P-waves
faster and occur first
S-waves
slower and occur second
lag time
the difference between the s-wave and the p-wave. relates to the distance from the epicenter. the longer the lag time the further the seismic station is from the epicenter
earth covered with water
3/4
% of fresh water
0.8%
water used brushing teeth
5 gallons
water a family uses each day
400 gallons
acids
pH less than 7
bases
pH greater than 7
neutral
pH equal to 7
pH
a measure of how acidic or basic liquids are
Basic (6) examples
household lye bleach ammonia baking soda sea water swimming pool water
neutral example
distilled water
Acidic (6) examples
rain water orange juice vinegar coca-cola lemon juice battery acid
soap consumption
the soap is reacting with the calcium and magnesium, effectively removing them as discrete minerals from the water. the water then tests soft
can cause pH to drop
rainwater
Iron
forms from dissolution of pyrite
mainly abundant in acid mine drainage
chlorine
not naturally occurring. usually added to tap water to kill bacteria
copper
related to blue-green staining on faucets
bitter tasting water
hard water
means containing calcium or magnesium.
wells/aquifers within limestone or dolomite.
related to scale build up in pipes
the harder the water the more soap is required.
durability (most to least) 3
granite
marble
sandstone
limestone environment
warm shallow sea
sandstone environment
beach, desert, or river channels
materials that react with acid
limestone or marble
properties of slate
foliated, small crystals, hard to distinguish texture
minerals found in granite
orthoclase feldspar, quartz, plagioclase feldspar, mica and amphibole
minerals found in gabbro
predominantly plagioclase and pyroxene (augite) with lesser olivine.
