maps Flashcards
no distortion
globe
polar regions extremely distorted
Mercator- straight lines
useful for topographic maps
polyconic
longitude lines converge
shoe roads and political boundaries
highway maps
show elevation
topographic maps
show rocks that are exposed at the surface of the earth
geologic maps
show very specific things
specialized maps
grid system to locate places on the earths surface
the earth is divided into degrees
latitude and longitude
1 degree can be divided into how many mins
60
1 min can be divided into how many secs
60
parallel to the equator
distance in degrees north or south of the equator
latitude lines
equator
0 degrees
North Pole
90° N
South Pole
90° S
70 miles
1° of latitude
1 min is 1.15 miles
nautical mile
meridians prime meridians 0 degrees is arbitrarily picked at Greenwich, England connect pole to pole lines coverage at the poles not parallel, converge at poles perpendicular to the equator
longitude lines
1:24000
numerical scale
bar scale
graphical scale
conversion
verbal scale
1:1000000
show us area at low detail
zoomed out
small scale maps
1:24000
show a small area in lots of detail
zoomed in
large scale maps
used to interpret symbols
map legend
used on small scale to show more detail- large scale maps
inset maps
show the last of the land by using contour lines
show the elevation above sea level
usually in feet
every point on a contour line is the exact same elevation
topographic maps
brown
topography
red
highways
blue
water
black
man made objects
green
vegetation over 3 feet
white
no vegetation or vegetation under 3 feet
the change in elevation between adjacent contour lines
common interval is 20 feet
in very flat terrain, the interval might only be 5 feet
in steep terrain, the interval might be 40 or even 80 feet
contour interval
every 5th line is bold
contour line
area is steep
contour lines are close together
contour lines are superimposed
cliff
contour lines are spaced far apart
gentle slope
contours V upstream
rivers
closed loops
hills
multiple hills
ridges
shown with hachure marks
depression
gradient slope formula
change in elevation between two points in feet divided by change in horizontal distance between 2 points in miles
longitude of the prime meridian
0
longitude of international dateline
180
why is the distance between longitude lines not consistent
the lines converge at poles
represent 3 dimensional space in 2 dimensions
drawn to scale
used to be hand drawn
now are mostly made by air photos and satellites
maps
