<P> In geology , a fault is a planar fracture or discontinuity in a volume of rock , across which there has been significant displacement as a result of rock - mass movement . Large faults within the Earth 's crust result from the action of plate tectonic forces , with the largest forming the boundaries between the plates , such as subduction zones or transform faults . Energy release associated with rapid movement on active faults is the cause of most earthquakes . </P>
<P> In geology , a fault is a planar fracture or discontinuity in a volume of rock , across which there has been significant displacement as a result of rock - mass movement . Large faults within the Earth 's crust result from the action of plate tectonic forces , with the largest forming the boundaries between the plates , such as subduction zones or transform faults . Energy release associated with rapid movement on active faults is the cause of most earthquakes . </P>
what geological feature is a fracture in earth 's crust
what geological feature is a fracture in earth 's crust
a fault
a fault