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砂箱实验模拟了正向和外向裂谷的三维演化过程，裂谷作用的方位角α（α为裂谷轴和伸展方向之间的夹角）分别取90°（正向裂谷）、75°、60和45°（斜向裂谷）。实验模型分别在水平和垂向上做切面。正向裂谷模型以长、直的边界断层和内断层与拉伸方向正交为特征。外向裂谷模型以短、分段的边界断层和内部断层为特征。在科向裂谷模型中，边界断层呈雁行排列，并与基底伸展带平行；裂谷内断层与伸展方向大角度相交。在中度外向和斜向裂谷（α＝60°和45°）中，随着拉伸量的增加，裂谷内断层朝着平行于边界断层方向发生旋转。在所有实验中都没有发现走滑或斜滑断层。所有模型中，裂谷边界断层和内部断层沿走向分段，在断层重叠部位形成中继断坡构造。共轭正断层组成的调节带能够实现裂谷系统走向方向上半地堑不对称性的转变和沉降中心的错开。实验产生的断层样式可与现代年轻裂谷中断层样式进行很好的对比，在这些现代裂谷中，也没有发现由基底控制的走滑或科滑转换断层。实验模型得出断层的几何形态可以作为识别正向和斜向裂谷中断层样式的样板。
The sand box experiment simulates the three-dimensional evolution of the forward and outward rifts. The azimuth α of rifting (α is the angle between the rift axis and the extension direction) is 90 ° (forward rift), 75 °, 60 and 45 ° (oblique rift). The experimental model is made horizontally and vertically, respectively. The forward rift model is characterized by long and straight boundary faults and the fault is orthogonal to the extension direction. Outward rift models are characterized by short and segmented boundary faults and internal faults. In the section-to-rift model, the boundary faults are geese arranged in flight and parallel to the extensional zone of the basement; faults intersect with the extensional direction at large angles. In the moderate extrusions and oblique rifts (α = 60 ° and 45 °), the faults within the rift turn toward parallel to the boundary fault as the amount of tension increases. No slippage or sloping faults were found in all experiments. In all the models, the rift boundary fault and the internal fault are segmentalized along the strike to form a relay fault structure at the fault overlap. The adjustment band composed of conjugate normal faults can realize the transformation of the half-graben asymmetry in the strike direction of the rift system and the misalignment of the subsidence center. The experimentally generated fault pattern is well comparable to the modern young rift faulting pattern in which no basement-controlled strike-slip or slip-transition faults were found. The experimental model shows that the fault geometry can be used as a model to identify faults in the forward and oblique rifts.