Nonlinear fault damage zone scaling revealed through analog modeling

Abstract Fault damage zones strongly influence fluid flow and seismogenic behavior of faults are thought to scale linearly with fault displacement until reaching a threshold thickness. Using analog modeling different frictional layer thicknesses, we investigate zone dynamic evolution during normal growth. We show that experimental growth is not linear but progressively tends toward thickness, being larger in the thicker models. This thickness increases significantly at segment relay zones. As approached, failure mode transitions from dilational shear isochoric shear. process affects whole develops as consequence linkage inferred nature when matures. These findings suggest widths limited both by scales mechanical unit modes, ultimately controlled lithology deformation conditions.