contour survey的意思|示意

The contour of sea surface magnetic field is an essential map in Marine magnetic survey. By using this map, the position of underwater ferromagnet is easily defined.

海面磁场等值线图是海洋磁探测的最基本图件，从中可以确定水下铁磁体的位置所在。

Though she spent much of the time with her nose in one-inch Ordnance Survey maps, tracking the contour lines, she found them a “coarse instrument” for her purpose.

虽然她皓首穷经地埋首于英国四十万分之一比例尺的全国地形测量地图，追寻每一条等高线，对她的研究目标来说，她仍觉得这份地图算是「粗糙的工具」。