They differ somewhat from bathymetric charts which are virtually topographic maps of the ocean floor. 它们与水深图稍有不同，后者实际上是洋底地形图。
The survey system can make measurement of the depth of the mud scum and can automatically plot a navigable water depth chart with the acquired data of water depth. 该系统可以进行浮泥层水深测量并将水深数据经整理后自动绘制成适航水深图。
