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Strike-slip landscapes are often associated with a suite of characteristic geomorphic features that provide primary evidence for interpreting fault slip histories. Here we explore the role of shutter ridges, areas of relief advected laterally along faults, in generating two classic strike-slip processes: progressive lateral offset of channels and stream capture. Landscape models and comparative analysis of the Marlborough Fault System, NZ, show that the length of channel offsets observable in a landscape is primarily controlled by the length of shutter ridges. In our simple landscape model, this scale is controlled by the drainage spacing, and therefore by the geometry of the mountain range. In a more complex landscape, this scale may be controlled by lithologic or structural contrasts. We also find that shutter ridge relief inhibits stream capture, especially at slow fault slip rates relative to hillslope erosion rates. In this case, lateral drainage advection enables streams to "outrun" capture.

Plain Language Summary Many geoscientists look for horizontal stream deflection in a landscape in order to identify evidence of strike-slip faulting-a type of deformation that moves blocks of crust horizontally past one another. Based on results from this study, we suggest caution with this approach. Using a computer model of landscapes and comparison to the Marlborough Fault System of New Zealand, we determine that the "classic" signatures of strike-slip faulting, long stream channel offsets that flow parallel to the fault, and stream capture, which re-directs streams into neighboring channels, are controlled not by fault slip properties, such as slip rate or maturity, but by the presence and stature of shutter ridges (areas of high topography carried along the fault). In particular, we find that channel offset length is largely dictated by the length of the shutter ridge causing the obstruction. Stream capture rate is influenced by both length and height of shutter ridges, as well as fault slip rate and the rate at which the landscape is eroding. The bottom line from this study is that without topographic elements to impede the courses of streams, even a very long-lived and fast-slipping purely strike-slip fault may not develop and sustain long channel offsets.