Persistence (discontinuity)

Persistence determines the possibilities of relative movement along a discontinuity in a soil or rock mass in geotechnical engineering.

[1][2] A persistent discontinuity is a continuous plane in a soil or rock mass.

A non-persistent discontinuity ends in intact soil or rock.

Before movement of the material on both sides of a non-persistent discontinuity is possible, the discontinuity has to extend and break through intact material.

A discontinuity might be persistent in dip direction but be not persistent perpendicular to the dip direction or vice versa.