What are the names of canyons in Antarctica?

Answer 1

Ninety-eight percent of Antarctica is covered with an ice sheet, and most of the lower parts of the continent under the ice sheet are called trenches.

According to the CIA, notably, the Bentley Subglacial Trench in Marie Byrd Land of West Antarctica: [ 80°S, 115°W] lies 2,555 meters or 8,382 feet below sea level. Named, then, there is no lower point on earth not covered by water.

In 2014, according to the Geological Society of America Bulletin, a massive sub-glacial valley up to 3 kilometers -- 1.9 miles -- deep and more than 25 kilometers -- 15.5 miles was discovered under the Ellsworth Mountains. To date, it has not been named.

Because not all trenches have been identified, there is no comprehensive list of trench names.