The Effects of Sedimentation Rates on Growth and Interaction of Normal Faults: New Insights From Physical Modelling

Understanding the early‐stage development of normal faults is crucial for deciphering tectono‐stratigraphic evolution in rift basins. Two end‐member models the isolated model and the constant‐length model have been proposed, yet these available models cannot well explain the mechanisms controlling incipient fault propagation, particularly regarding the influence of syn‐sedimentary processes. The Chennan Fault in the Dongying Depression, where contrasting sedimentation rates between the Liangjialou and Chenguanzhuang zones produced distinct hanging‐wall fault patterns, provides an ideal natural case to investigate this problem. We present scaled physical experiments examining normal fault development under varying sedimentation rates, employing particle image velocimetry (PIV) and high‐resolution 3D laser scanning to quantify fault geometry evolution and displacement–length ( D max / L ) scaling relationships. Our experimental results reveal three fracture types in the hanging wall: isolated growth, coupled interference growth and superposition growth, the combination of which varies systematically with the sedimentation rate: at low rates, coupled interference and superposition growth dominate ( D max / L ≈ 10 −2 to 10 –1.75 ); at moderate rates, all three types coexist ( D max / L ≈ 10 −2 to 10 −1 ); at high rates, isolated and coupled interference growth prevail ( D max / L ≈ 10 −2 to 10 –0.75 ). The median D max / L ratio increases systematically with sedimentation rates. Comparison with seismic coherence data confirms that Model II, calibrated to the lower‐rate LJL zone, reproduces all three fault styles, while Model III, calibrated to the higher‐rate CGZ zone, generates simpler architectures dominated by isolated and coupled interference modes. These results demonstrate that sedimentation rates is a primary control on hanging‐wall fault architecture, and that early fault evolution may not conform to a single end‐member growth model, offering fresh insights for refining fault growth theories and structural interpretations of rift basins.