Reported deep sea danger in uncertain position.

Related Terms


A long, deep swell or undulation of the ocean often caused by a long-continued gale and sometimes a seismic disturbance and felt even at a remote distance. In shallow water the swell rises to a prominent height.


On the sea floor, a flat, gently sloping or nearly level region. Sometimes called ABYSSAL PLAIN in very deep water.


A place where ships in transit can find shelter from a storm. These are often man-made jetty enclosed areas along a featureless coastline where no nearby natural deep water harbors exist.


A deep sea expression for a sail repair, done with large herringbone stitches.


A very deep area of the ocean. The term is used to refer to a par- ticular deep part of the ocean, or to any part below 300 fathoms


A wave which breaks, either because it becomes unstable, usually when it reaches shallow water, or because it dashes against an obstacle. Instability is caused by an increase in wave height and a decrease in the speed of the trough of the wave in shallow water. The momentum of the crest, often aided by the wind, causes the upper part of the wave to move forward faster than the lower part. The crest of a wave which becomes unstable in deep water and topples over or 'breaks' is called a WHITECAP.


On the sea floor, a relatively narrow, deep depression with steep sides, the bottom of which generally has a continuous slope.


1. The part of a body of water deep enough for navigation through an area otherwise not suitable. It is usually marked by a single or double line of buoys and sometimes by ranges. 2. The deepest part of a stream, bay, or strait, through which the main current flows. 3. A name given to certain large straits, such as the English Channel. 4. A hollow bed through which water may run. 5. A band of radio frequencies within which a radio station must maintain its modulated carrier frequency to prevent interference with stations on adjacent channels. Also called FREQUENCY CHANNEL.


A light deep sea lead (30 to 50 pounds), used for sounding in water 20 to 60 fathoms


A deep fissure or rift in a glacier

Related questions

MarineProHelp 2018 - 2022