词条 | rock fan |
释义 | rock fan geology fan-shaped bedrock surface at the foot of a mountain, often where a stream flows out onto a piedmont slope. It is often covered with a thin veneer of alluvium and may be confused with an alluvial fan. Rock fans are usually quite steep (20° to 26° slope). It has been suggested that they represent the early stage of pediment development. See pediment. |
随便看 |
|
百科全书收录100133条中英文百科知识,基本涵盖了大多数领域的百科知识,是一部内容开放、自由的电子版百科全书。