Strike and dip

Strike and dip refer to the orientation or attitude of a geologic feature. The strike of a stratum or planar feature is a line representing the intersection of that feature with the horizontal. On a geologic map this is represented with a short straight line segment oriented parallel to the compass direction of the strike. Strike is usually given as a compass bearing (N25°E for example) in terms of east or west of north, or as a single three digit number representing the azimuth, where the lower number is usually given (where the example of N25°E would simply be 025, and the other value of 205 is discarded). The dip gives the angle below the horizontal of a tilted stratum or feature. The symbol is a short line attached and at right angles to the strike symbol pointing in the direction of inclination. Typically the angle of dip is included on a geologic map.
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