The green line indicates the main road, black dotted lines are trails, and there are markers for campsites, a picnic area, and a shuttle bus stop. With contour lines to indicate elevation, the topographic map in Figure below shows the terrain. How does the map of Bryce Canyon reveal the terrain of the region? Several principles are important for reading a topographic map:.
Contour lines show the 3-dimensional shape of the land Figure below. What does the spacing of contour lines indicate? Just to the right of the city of Stowe is a steep hill with a sharp rise of about ft that becomes less steep toward the right. Concentric circles indicate a hill. When contour lines form closed loops all together in the same area, this is a hill.
The smallest loops are the higher elevations and the larger loops are downhill. On the Stowe map, which hill has an elevation of feet? If you found Cady Hill, on the left side of the map, you are right. Hatched concentric circles indicate a depression, as seen in the Figure below. The hatch marks are short, perpendicular lines inside the circle.
The innermost hatched circle would represent the deepest part of the depression, while the outer hatched circles represent higher elevations. V-shaped expanses of contour lines indicate stream valleys. Where a stream crosses the land, the Vs in the contour lines point uphill. The channel of the stream passes through the point of the V and the open end of the V represents the downstream portion.
If the stream contains water, the line will be blue; otherwise, the V patterns indicate the direction water will flow. In the map of Stowe, where does a stream run downhill into a lake? Scales on topographic maps indicate horizontal distance. An animation showing contour lines and the slopes they represent. Therefore, a map will never be entirely up to date. Changes to the landscape and cultural features regularly occur such as roads, vegetation, and buildings , resulting in maps becoming dated, although the rate of obsolescence varies depending upon location.
Geoscience Australia develops and maintains topographic maps and data for a variety of applications. Of course, topographic maps are used for recreational purposes, such as travelling, hiking and orienteering, but they are also used by government and industry to assist with urban planning, mining, emergency management and the establishment of legal boundaries and land ownership. What is Map Scale? Topographic maps are generally large-scale maps that depict both the physical and man-made features of the landscape; and are distinctly characterized by the presence of contour lines that show the in-detail ground relief of the land.
Many man-made features are found on topographic maps, these include roads, rivers, railroads, towns, mountains, elevation and vegetation types 1. Knowing what features are generally found on Topographic maps is always handy but the real skill you want, is being able to understand what the map is showing you.
This is an invaluable skill that will allow you to adventure into the unknown with nothing more than a paper map and have the confidence to navigate your way through unknown terrain safely. The four main features on Topographic maps that you will need to master are:. As mentioned previously, contour lines are the defining feature of topographic maps - understanding them and how they function is the most crucial part of being able to successfully read a topographic map.
Contour lines allow you to visualize the 3D world on a 2D map and identify specific features of the landscape, such as valleys, ridges, slopes, mountains, hills and spurs.
This is an essential skill needed when using topographic maps to navigate in the wilderness or areas that lack identifiable man-made features [2]. How contour lines show a pair of small hills [3].
A Contour line is a line on a map that joins points of equal height above sea level, allowing for an easy visual representation of the height of mountains, steepness of slopes and the general sense of the terrain. The shape of the contour lines is an important piece of information that allows you to identify features on the map such as peaks, ridges, passes or valleys.
Smaller circular shapes are most likely showing you peaks or hills, whereas V-shapes are probably showing you a spur or ridge [5]. Slope steepness and rapid elevation changes are indicated by how close the contour lines are to one another, the steeper the slope the closer the contour lines will be together.
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