Key:seamark:sea_area:category

Categories sea areas (CATSEA)

Values

Classification of an area based on its physical characteristics.

Category	seamark:sea_area:category	Definition
Gat	gat	A natural or artificial passage or channel through shoals or steep banks, or across a line of banks lying between two channels.
Bank	bank	An elevation over which the depth of water is relatively shallow, but normally sufficient for safe surface navigation.
Deep	deep	In oceanography, an obsolete term which was generally restricted to depths greater than 6,000 m
Bay	bay	An indentation in the coastline.
Trench	trench	A long narrow, characteristically very deep and asymmetrical depression of the sea floor, with relatively steep sides.
Basin	basin	A depression, characteristically in the deep sea floor, more or less equidimensional in plan and of variable extent.
Flat	flat	A level tract of land, as the bed of a dry lake or an area frequently uncovered at low tide. Usually in plural.
Reef	reef	Rock lying at or near the sea surface that may constitute a hazard to surface navigation.
Ledge	ledge	A rocky formation continuous with and fringing the shore.
Canyon	canyon	A relatively narrow, deep depression with steep sides, the bottom of which generally has a continuous slope, developed characteristically on some continental slopes.
Narrowa	narrows	A navigable narrow part of a bay, strait, river, etc.
Shoal	shoal	An offshore hazard to surface navigation that is composed of unconsolidated material.
Knoll	knoll	A relatively small isolated elevation of a rounded shape.
Ridge	ridge	(a) A long, narrow elevation with steep sides. (b) A long, narrow elevation often separating ocean basins. (c) The linked major mid-oceanic mountain systems of global extent.
Seamount	seamount	A large isolated elevation, greater than 1000m in relief above the sea floor, characteristically of conical form.
Pinnacle	pinnacle	Any high tower or spire-shaped pillar or rock or coral, alone or cresting a summit. It may extend above the surface of the water. It may or may not be a hazard to surface navigation.
Abyssal plain	abyssal_plain	An extensive, flat, gently sloping or nearly level region at abyssal depths.
Plateau	plateau	A flat or nearly flat area of considerable extent, dropping off abruptly on one or more sides.
Spur	spur	A subordinate elevation, ridge or rise projecting outward from a larger feature.
Shelf	shelf	A zone adjacent to a continent (or around an island) and extending from the low water line to a depth at which there is usually a marked increase of slope towards oceanic depths.
Trough	trough	A long depression of the sea floor characteristically flat bottomed and steep sided and normally shallower than a trench.
Saddle	saddle	A broad pass, resembling in shape a riding saddle, in a ridge or between contiguous seamounts.
Abyssal hills	abyssal_hills	A tract, on occasion extensive, of low (100-500m) elevations on the deep sea floor.
Apron	apron	A gently dipping featureless surface, underlain primarily by sediment, at the base of any steeper slope.
Archipelagic apron	archipelagic_apron	A gentle slope with a generally smooth surface on the sea floor, characteristically found around groups of islands or seamounts.
Borderland	borderland	A region adjacent to a continent, normally occupied by or bordering a shelf, that is highly irregular with depths well in excess of those typical of a shelf.
Continental margin	continental_margin	The zone, generally consisting of shelf, slope and rise, separating the continent from the abyssal plain or deep sea floor.
Continental rise	continental_rise	A gentle slope rising from the oceanic depths towards the foot of a continental slope.
Escarpment	escarpment	An elongated and comparatively steep slope separating or gently sloping areas.
Fan	fan	A relatively smooth, fan-like, depositional feature normally sloping away from the outer termination of a canyon or canyon system.
Fracture zone	fracture_zone	An extensive linear zone of irregular topography of the sea floor, characterized by steep-sided or asymmetrical ridges, troughs or escarpments.
Gap	gap	A narrow break in a ridge or a rise.
Guyot	guyot	A seamount having a comparatively smooth flat top.
Hill	hill	A small isolated elevation (see also abyssal hills).
Hole	hole	A local depression, often steep sided, of the sea floor.
Levee	levee	A depositional embankment bordering a canyon, valley or deep-sea channel.
Median valley	median_valley	The axial depression of the mid-oceanic ridge system.
Moat	moat	An annular depression that may not be continuous, located at the base of many seamounts, islands and other isolated elevations.
Mountains	mountains	A large and complex grouping of ridges and seamounts.
Peak	peak	A prominent elevation either pointed or of a very limited extent across the summit.
Province	province	A region identifiable by a group of similar physiographic features whose characteristics are markedly in contrast with surrounding areas.
Rise	rise	(a) A broad elevation that rises gently and generally smoothly from the sea floor. (b) The linked major mid-oceanic mountain systems of global extent.
Sea channel	sea_channel	A continuously sloping, elongated narrow depression commonly found in fans or abyssal plains and customarily bordered by levees on one or both sides.
Seamount chain	seamount_chain	Several seamounts in linear or orcuate alignment.
Shelf-edge	shelf-edge	A narrow zone at the seaward margin of a shelf along which is a marked increase of slope.
Sill	sill	A sea floor barrier of relatively shallow depth restricting water movement between basins.
Slope	slope	The slope seaward from the shelf edge to the upper edge of a continental rise or the point where there is a general reduction in slope.
Terrace	terrace	A relatively flat horizontal or gently inclined surface, sometimes long and narrow, which is bounded by a steeper ascending slope on one side and by a steeper descending slope on the opposite side.
Valley	valley	A relatively shallow, wide depression, the bottom of which usually has a continuous gradient. This term is generally not used for features that have canyon-like characteristics for a significant portion of their extent.
Canal	canal	An artificial water course used for navigation.
Lake	lake	A large body of water entirely surrounded by land.
River	river	A relatively large natural stream of water.
Reach	reach	A straight section of a river, especially a navigable river between two bends or an arm of the sea extending into the land.

See also

• Sea areas