海底
seabed;sea floor; bottom of the sea
~地形sea floor relief /~采矿submarine mining; undersea mining; ocean mining/ ~电报submarine telegraph;cablegram/~电缆(线)submarine cable /~管理局seabed authority/~火山submarine volcano/~技术undersea technology/~架submarine shelf/~开发seabed exploration/~勘探submarine survey and exploration/~矿submarine mine/~爬行器bottom crawler/~区域seabed area/~山sea-mount /~生物benthos; benthon;bottom inhabitants/~实验室sealab/~水雷ground mine (or torpedo)/~延伸sea floor spreading/~养殖bottom culture /~油田offshore oilfield/~淤泥bottom silt/~资源seabed resources;submarine resources