What features are generally found on a geologic map?
1. Map
Geologic maps are idealized pictures of the distribution of earth materials at or near the ground surface.
2. Explanation
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The description of map units defines each earth material (map unit) shown on the geologic map. Each map unit is defined by its own unique color, name-abbreviation, and text describing physical characteristics.
3. Scale
The map scale relates the size of geologic features shown on the map to the actual size of those features.
A scale of 1:100,000 means that one unit (an inch, for example) is equal to 100,000 units in real life.
4. Symbols
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This area shows diagrams, names, and descriptions of every symbol used on the map.
5. Correlation of map units
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The correlation of map units shows the relative age of each type of earth material (map unit) shown on the map.
This element may be absent from a geologic map when the units simply stack one on top of another, from oldest to youngest. In this case, the explanation does double duty, describing each unit and presenting it in the order of its relative age.
