Rule 1 – every point of a contour line has the same elevation. Rule 2 – contour lines separate uphill from downhill. Rule 3 – contour lines do not touch or cross each other except at a cliff. Rule 4 –
every 5th contour line is darker in color
.
What are the 5 rules of a topographic map?
- Contour Lines Never Cross. …
- Measuring Steepness.
- Stream Flow Direction.
- Contours Close.
- Concentric Circles.
- Elevation Between Lines.
What are 3 types of contour lines?
Contour lines are of three different kinds. They are
the Index lines, Intermediate lines and the Supplementary lines
.
What is every 5 contour line called?
However, the elevations represented by the contour lines are not always labeled on each line (see Figure 3.2). Instead, every 5
th
contour line is labeled with an elevation, and is darkened; such a contour line is called
an index contour
.
What are 4 types of contour lines?
- Isopleth. Isopleth on a contour map connects the places having the same value of some measurable quantity of geographical or meteorological phenomena. …
- Isohyet. …
- Isobar. …
- Isobath. …
- Isohaline. …
- Isotherm. …
- Isohel. …
- Isohume.
How do you get contour lines?
The two ways to establish a contour map are
the cross-section method and the trace contour method
. To use the cross-section method, set a control or reference line at the center of the lot, then lay out and stake a grid; the elevation is determined at each stake in the grid relative to a benchmark.
How do the lines indicate which side of the mountain is the steepest?
Contour lines that are close together
indicate a steep slope, where the elevation changes quickly over a short distance. If the contour lines are so close together that they seem to touch, they indicate a very steep slope, such as a cliff. In contrast, contour lines that are far apart indicate a gentle slope.
Why can’t contour lines cross?
Contour lines never cross on a topographic map
because each line represents the same elevation level of the land
.
What is the space between contour lines called?
A contour interval
is the vertical distance or difference in elevation between contour lines. Index contours are bold or thicker lines that appear at every fifth contour line.
What is a depression contour line?
A closed contour,
inside of which the ground or geologic structure is at a lower elevation than that outside
, and distinguished on a map from other contour lines by hachures marked on the downslope or downdip side.
What is major and minor contour lines?
The major contour lines at the decades
are logarithmic values that are equally spaced
, and the minor contour lines are linear values that are logarithmically spaced.
Does Google Earth show contour lines?
This KML network link displays a map overlay for USGS Contours (http://viewer.nationalmap.gov/) in Google Earth. To get started, simply download usgs-contours-overlay-for-google-earth. Or checkout all 4 USGS The National Map map overlays on this site. …
What are the types of contour line?
- Index lines are the thickest contour lines and are usually labeled with a number at one point along the line. …
- Intermediate lines are the thinner, more common, lines between the index lines.
What are the basic features of contour lines?
- Must close on themselves, on or off the map.
- Perpendicular to the direction of max. …
- Slope between them is assumed uniform.
- The distance between them indicates the steepness of the slope, gentle or steep.
- Irregular signify rough, smooth signify gradual slopes.
How does Google Earth measure contour?
Open Google Earth. Click File | Open,
select the KML file
, and click Open. The contour map is loaded and displayed over the aerial photo. The color and transparency properties are retained.
