dirt seal

例句：

1. 1. The dirt seal on the doorwas worn away by years of use.
   门上的泥土密封因年久而磨损。
2. 2.The soil seal around the base of thetree is a sign of its age.
   树根周围的土壤密封是其年龄的标志。
3. 3.The mud seal on the riverbank hasbeen disturbed by recent flooding.
   河岸边泥土密封被近期的洪水搅动。