Rake (geology)
In structural geology, rake is formally defined as "the angle between a line and the strike line of the plane in which it is found", measured on the plane. The three-dimensional orientation of a line can be described with just a plunge and trend. The rake is a useful description of a line because often features follow along a planar surface. In these cases the rake can be used to describe the line's orientation in three dimensions relative to that planar surface. One might also expect to see this used when the particular line is hard to measure directly. The rake always sweeps down from the horizontal plane.Rake is used to describe the direction of fault motion with respect to the strike :
- left-lateral strike slip: rake near 0°
- right-lateral strike slip: rake near 180°
- normal: rake near −90°
- reverse/thrust: rake near +90°
