Strike and Dip
Many features observed in geology are planes or lines, and their orientation is commonly referred to as their attitude. These attitudes are specified with two angles.
For a line, these angles are called the trend and the plunge. The trend is the compass direction of the line, and the plunge is the downward angle it makes with a horizontal plane.
For a plane, the two angles are called its strike (angle) and its dip (angle). A strike line is the intersection of a horizontal plane with the observed planar feature (and therefore a horizontal line), and the strike angle is the bearing of this line (that is, relative to geographic north or from magnetic north). The dip is the angle between a horizontal plane and the observed planar feature as observed in a third vertical plane perpendicular to the strike line.
Read more about this topic: Orientation (geometry), Plane in Three Dimensions
Famous quotes containing the words strike and/or dip:
“So, instead of spending my strength quarreling with the hand, I would strike for the heart of that great tyranny.”
—Jane Grey Swisshelm (1815–1884)
“A just thinker will allow full swing to his skepticism. I dip my pen in the blackest ink, because I am not afraid of falling into my inkpot.”
—Ralph Waldo Emerson (1803–1882)