Strike and dip

Orientation of a geologic feature

In geology, strike and dip is a measurement convention used to describe the plane orientation or attitude of a planar geologic feature. A feature's strike is the azimuth (relative to north) of an imagined horizontal line across the plane, and its dip is the angle of inclination (or depression angle) measured downward from horizontal. They are used together to measure and document a structure's characteristics for study or for use on a geological map.

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