Trench Glacier [SEP] continent
Trench Glacier
Trench Glacier () is a deeply entrenched glacier extending along the east coast of Alexander Island, Antarctica, 6 nautical miles (11 km) long and 2 nautical miles (3.7 km) wide, which flows east into the George VI Ice Shelf that occupies George VI Sound immediately south of Mount Athelstan. The mouth of this glacier was first photographed from the air on November 23, 1935, by Lincoln Ellsworth, and it was mapped from these photos by W.L.G. Joerg. Trench Glacier was surveyed in
trench was filled by an enormous glacier. As the glacier moved southward it carved out the trench. The Polson Moraine, near present-day Polson, Montana, marks the southernmost extent of the glacier during the last ice age and thus is the site of the glacier's terminal moraine.
The large size of the Polson Moraine indicates that the glacier stalled here for many years before retreating. As the climate warmed, a portion of the glacier in the Mission Valley receded more slowly than the main body, which kept the