“岩栓”的英语？

含磁铁岩的岩栓不规则地分布于关键带的基底以上.Magnetitite - bearing plugs are found erratically from the base of the Critical Zone.岩栓的边缘通常是不露出的,因而不能确定其包裹的物质是什么.The rim of the plugs is usually not exposed and the enveloping material cannot be a...