The breakthrough curve (BTC) of prefential flow was asymmetirc, which was proved by the analysis on its average penetrating time and the extent of its spreading and lagging.

• 同时采用驻留力矩分析穿透曲线（BTC）的平均穿透时间以及蔓延扩散和拖尾程度，结果表明优先流的穿透曲线具有不对称性。