The Hudson Canyon is a

submarine canyon A submarine canyon is a steep-sided valley cut into the seabed of the continental slope, sometimes extending well onto the continental shelf, having nearly vertical walls, and occasionally having canyon wall heights of up to 5 km, from c ...

that begins from the shallow outlet of the

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

at the mouth of the

Hudson River The Hudson River is a river that flows from north to south primarily through eastern New York. It originates in the Adirondack Mountains of Upstate New York and flows southward through the Hudson Valley to the New York Harbor between N ...

. It extends out over seaward across the continental shelf finally connecting to the deep

ocean basin In hydrology, an oceanic basin (or ocean basin) is anywhere on Earth that is covered by seawater. Geologically, ocean basins are large  geologic basins that are below sea level. Most commonly the ocean is divided into basins fol ...

at a depth of 3 to 4 km below

sea level Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardise ...

. It begins as a natural channel of several kilometers width, starting as a 20–40 m depression at Hudson Channel southward from Ambrose Light, then carving through a deep notch of about 1 km depth in the shelf break, and running down the continental rise. Tidally associated flows of about up and down the deeper parts of the canyon have been recorded. As silt, sand and mud are carried down the Hudson River, they flow into the canyon and out into the deep sea. The Hudson Canyon proper is located about east of the mouth of the Hudson River off the New Jersey coast. Its walls rise from the canyon floor, making it comparable to the Grand Canyon, whose cliffs are over deep and long. It is the largest known ocean canyon off the East Coast of the United States, and one of the largest submarine canyons in the world. The canyon is located near the 100 meter

isobath Bathymetry (; ) is the study of underwater depth of ocean floors (''seabed topography''), lake floors, or river floors. In other words, bathymetry is the underwater equivalent to hypsometry or topography. The first recorded evidence of water de ...

on the continental shelf and is deep at the base of the continental slope. Over an distance, the average slope of the canyon floor is 1.5°. At this point the canyon is as much as wide (from east rim to west rim) and as much as deep from canyon rim to canyon floor across the continental slope. The floor of the canyon is less than wide across the upper part of the slope and broadens to about at the base of the slope. The canyon was last exposed during the last ice age, over 10,000 years ago, when the sea level was about lower and the mouth of the Hudson River was near the edge of the continental shelf, about east of its present site. The river discharged sediment that helped carve the canyon aided by underwater avalanches of mud and sand. Recent maps of the canyon reveal tributaries of an extraordinary underwater drainage network that is strikingly similar to terrestrial rivers. Tidal currents sweep up and down the channel; and on occasion, during big storms, cold ocean water is pushed up the Hudson Canyon to spread out on the shelf. Thus the Hudson Canyon continues to be cut by traveling sediments.Butman, et al., 2006 "Hudson Canyon" also designates a location marked by a navigational buoy indicating the seaward end of the vessel traffic separation scheme of the Hudson Canyon– Ambrose lanes which lead into and out of New York Harbor for Atlantic shipping.

References

;Notes ;Bibliography * Butman, Bradford, Twichell, David C., Rona, Peter A., Tucholke, Brian E., Middleton, Tammie J., and Robb, James M., 2006
"Sea Floor Topography and Backscatter Intensity of the Hudson Canyon Region Offshore of New York and New Jersey"
U.S. Geological Survey Open-File Report 2004-1441, Version 2.0.

External links

{{Spoken Wikipedia, Hudson_Canyon_220820.flac, date=August 20, 2022

Submarine canyons of the Atlantic Ocean Hudson River