Bentley Subglacial Trench
The Bentley Subglacial Trench (80°S, 115°W) is a vast topographic trench in Marie Byrd Land.
At 2,555 meters (8,382 ft) below sea level, it (along with the deepest points within the adjacent Byrd Subglacial Basin) is among the lowest points on the surface of the Earth not covered by ocean, although it is covered by ice.
The trench was named in 1961 after Charles R. Bentley who was the geophysicist in charge of the scientific expeditions in West Antarctica in 1957–59 that led to its discovery.
Starting in 2016, some hot anomalies were detected beneath Bentley Subglacial Trench and the Mount Sidley volcano.