Stratigraphic expression of the lateral propagation and growth of isolated fault-related uplifts

The lateral propagation of faults and folds is known to be an important process during the development of mountain belts, but little is known about the manner in which along-strike fault-fold growth is expressed in pre- and syntectonic (growth) strata. We use a coupled tectonic and stratigraphic model to investigate the along-strike stratigraphic expression of fault-related folds/uplifts that grow in both the transport and strike directions. We consider faults that propagate following a quadratic (nonself-similar evolution) or linear (self-similar evolution) scaling law, using different slip distributions per episode of fault propagation, under general background sedimentation. We find that the long-strike geometry of pre- and syntectonic strata and the geometry of growth axial surfaces reflect the mode of fault propagation. The geometry of strata observed in the model is similar to that observed in natural contractional structures when: (1) the evolution of the fault is nonself-similar, or (2) the fault grows as a result of thrust faulting events with similar displacements along strike that are terminated abruptly at the fault tips.