The bottom and top boundaries of overpressure compartments are ductile layers, as well as slip faults and overthrust faults which grew in the ductile layer.

• 非能干层及沿其发育的滑脱层和逆掩断层作为“压力封存箱”的顶板或底板，其在垂向上起到封隔压力的作用。