The Laurentian Abyss is an underwater depression off the eastern coast of Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 in the Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

. Not a trench, but more of an "underwater valley", it is estimated to be at most ~6,000 meters in depth. The Laurentian Abyss is a product of glaciation and water currents from the Saint Lawrence Seaway

Saint Lawrence Seaway

The Saint Lawrence Seaway , , is the common name for a system of locks, canals and channels that permits ocean-going vessels to travel from the Atlantic Ocean to the North American Great Lakes, as far as Lake Superior. Legally it extends from Montreal to Lake Erie, including the Welland Canal...

.

The trench is the site of hydrothermal vents with their own ecosystems independent of sunlight.

In popular culture

• The Laurentian Abyss was the covert rendezvous point for Soviet and American submarines in the 1990 technothriller film The Hunt for Red October
  The Hunt for Red October (film)
  The Hunt for Red October is a 1990 thriller film based on the novel of the same name by Tom Clancy. It was directed by John McTiernan and stars Sean Connery as Captain Marko Ramius and Alec Baldwin as Jack Ryan...
  
  . The location, however, was a departure from the book, and was not used in the original 1984 novel
  The Hunt for Red October
  The Hunt for Red October is a 1984 novel by Tom Clancy. The story follows the intertwined adventures of Soviet submarine captain Marko Aleksandrovich Ramius and CIA analyst Jack Ryan.The novel was originally published by the U.S...
  
   by Tom Clancy
  Tom Clancy
  Thomas Leo "Tom" Clancy, Jr. is an American author, best known for his technically detailed espionage, military science, and techno thriller storylines set during and in the aftermath of the Cold War, along with video games on which he did not work, but which bear his name for licensing and...
  
  .
• In the 2007 film Transformers, the body of Megatron, is dropped into the abyss. It is stated that the pressure and "sub-freezing" temperatures (presumably meaning below the freezing point of pure water at 1 atmosphere of pressure) at this depth would "crush and entomb" the evil alien robot. However, the film doubly erroneously states that the abyss is, at 7 miles (11.3 Km) below sea level, the deepest point on Earth; the actual deepest point is the Challenger Deep
  Challenger Deep
  The Challenger Deep is the deepest known point in the oceans, with a depth of to by direct measurement from submersibles, and slightly more by sonar bathymetry . It is located at the southern end of the Mariana Trench near the Mariana Islands group...
  
  , a section of the Mariana Trench
  Mariana Trench
  The Mariana Trench or Marianas Trench is the deepest part of the world's oceans. It is located in the western Pacific Ocean, to the east of the Mariana Islands. The trench is about long but has a mean width of only...
  
   in the Pacific Ocean
  Pacific Ocean
  The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
  
  . In the 2009 film Transformers: Revenge of the Fallen
  Transformers: Revenge of the Fallen
  Transformers: Revenge of the Fallen is a 2009 American science fiction-action film directed by Michael Bay and produced by Steven Spielberg. It is the sequel to the 2007 film Transformers and the second installment in the live-action Transformers series...
  
  , the remains are found at the bottom of the Abyss and Megatron is reactivated. Decepticon Protoforms are also seen climbing up a destroyed ship sinking into the Abyss waters. The film incorrectly states that the abyss is 9,300 fathom
  Fathom
  A fathom is a unit of length in the imperial and the U.S. customary systems, used especially for measuring the depth of water.There are 2 yards in an imperial or U.S. fathom...
  
  s deep, or about 17,000 meters.