Thurston Island is an ice-covered, glacially dissected island, long, wide and in area, lying a short way off the northwest end of

Ellsworth Land Ellsworth Land is a portion of the Antarctic continent bounded on the west by Marie Byrd Land, on the north by Bellingshausen Sea, on the northeast by the base of Antarctic Peninsula, and on the east by the western margin of the Filchner–Ron ...

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...

. It is the third-largest island of

, after

Alexander Island Alexander Island, which is also known as Alexander I Island, Alexander I Land, Alexander Land, Alexander I Archipelago, and Zemlja Alexandra I, is the largest island of Antarctica. It lies in the Bellingshausen Sea west of Palmer Land, Antarc ...

and

Berkner Island Berkner Island (also known as the Berkner Ice Rise or as Hubley Island) is an Antarctic ice rise, where bedrock below sea level has caused the surrounding ice sheet to create a dome. If the ice cap were removed, the island would be underwater. B ...

. The island was discovered from the air by Rear Admiral

Byrd Byrd commonly refers to: * William Byrd (c. 1540 – 1623), an English composer of the Renaissance * Richard E. Byrd (1888–1957), an American naval officer and explorer Byrd or Byrds may also refer to: Other people * Byrd (surname), includin ...

on February 27, 1940, who named it for W. Harris Thurston, a New York textile manufacturer, designer of the windproof "

Byrd Cloth Byrd Cloth is a type of fabric similar to Grenfell Cloth which was designed in the 1934 by Harris Thurston and heavily promoted by Antarctic explorer Richard Byrd. The material was considered windproof, yet the weave allowed some air to penetrate ...

" and sponsor of Antarctic expeditions. Thurston Island is separated from the mainland by

Peacock Sound Peacock Sound is an ice-filled sound, long and wide, separating Thurston Island from the Eights Coast of Ellsworth Land in Antarctica. The sound is occupied by the western part of the Abbot Ice Shelf, and is therefore not navigable by ships. ...

, which is occupied by the western portion of

Abbot Ice Shelf The Abbot Ice Shelf is an ice shelf long and wide, bordering Eights Coast from Cape Waite to Pfrogner Point in Antarctica. Thurston Island lies along the northern edge of the western half of this ice shelf; other sizable islands (Sherman, ...

. It divides

Bellingshausen Sea The Bellingshausen Sea is an area along the west side of the Antarctic Peninsula between 57°18'W and 102°20'W, west of Alexander Island, east of Cape Flying Fish on Thurston Island, and south of Peter I Island (there the southern ''Vostokkyste ...

to the east from Amundsen Sea to the west. Originally mistaken as a

peninsula A peninsula (; ) is a landform that extends from a mainland and is surrounded by water on most, but not all of its borders. A peninsula is also sometimes defined as a piece of land bordered by water on three of its sides. Peninsulas exist on all ...

, the feature was not recognised an island until 1960.

Geography

The western extremity of the island is

Cape Flying Fish Cape Flying Fish (, also known as Cape Dart) is an ice-covered cape which forms the western extremity of Thurston Island. It was discovered by Richard E. Byrd and members of the US Antarctic Program in a flight from the USS ''Bear'' in Februa ...

. The eastern extremity is Cape Annawan, off

Tierney Peninsula Tierney Peninsula () is an ice-covered peninsula about 14 nautical miles (26 km) long, between Savage Glacier and Morgan Inlet in the east end of Thurston Island. The east extremity of the peninsula (and Thurston Island overall) is Cape An ...

. The southeast end of the island is Cape Walker. The island is divided south-north by the

Walker Mountains Walker Mountains () is a range of peaks and nunataks which are fairly well separated but trend east–west to form the axis, or spine, of Thurston Island in Antarctica. They were discovered by Rear Admiral Byrd and members of the US Antarctic Se ...

, a range of peaks and nunataks. Several other peaks are situated on the

Edwards Edwards may refer to: People * Edwards (surname) * Edwards family, a prominent family from Chile * Edwards Barham (1937-2014), a former member of the Louisiana State Senate * Edwards Pierrepont (1817–1892), an American attorney, jurist, and ora ...

and

Noville Peninsula Noville Peninsula () is a high ice-covered peninsula about 30 nautical miles (60 km) long, between Peale and Murphy Inlets on the north side of Thurston Island in Antarctica. It was delineated from aerial photographs made by U.S. Navy Op ...

s. There are many glaciers on Thurston Island.

Features by coast

North coast

The north coast of the island is indented by a series of alternating

inlets An inlet is a (usually long and narrow) indentation of a shoreline, such as a small arm, bay, sound, fjord, lagoon or marsh, that leads to an enclosed larger body of water such as a lake, estuary, gulf or marginal sea. Overview In marine geogra ...

and peninsulas. Cape Petersen forms the westernmost portion of the northern coast. East of that is

Jones Peninsula Jones Peninsula () is an ice-covered peninsula west of Hughes Peninsula in northwest Thurston Island, Antarctica. It was named by the Advisory Committee on Antarctic Names after Ensign Robert H. Jones, navigator and second pilot of PBM Mariner ...

, then

Dyer Point Dyer Point () is an ice-covered point just west of Hughes Peninsula on the north coast of Thurston Island. It was first plotted from air photos taken by U.S. Navy Operation Highjump in December 1946, and was named by the Advisory Committee on Ant ...

and

Hughes Peninsula Hughes Peninsula () is an ice-covered peninsula about long, lying west of Henry Inlet on the north side of Thurston Island, Antarctica. At the northeast end of the peninsula is ice-covered Cape Davies. These features were plotted from air phot ...

Henry Inlet Henry Inlet is a narrow, ice-filled inlet about long, indenting the north coast of Thurston Island, Antarctica, immediately east of Hughes Peninsula. The inlet was first plotted from air photos taken by U.S. Navy Operation Highjump, 1946–4 ...

indents the coast to the east, and

Tinglof Peninsula Tinglof Peninsula () is an ice-covered peninsula, 10 nautical miles (18 km) long, between Henry and Wagoner Inlets on the north side of Thurston Island. It was delineated from aerial photographs taken by U.S. Navy Operation Highjump in Dece ...

forms its eastern shore.

Wagoner Inlet Wagoner Inlet () is an ice-filled inlet between Tinglof Peninsula and Starr Peninsula on the north side of Thurston Island. It was delineated from aerial photos taken by U.S. Navy Operation Highjump in December 1946. It was named by the Advi ...

is east of that, followed by

Starr Peninsula Starr Peninsula () is an ice-covered peninsula about 10 nautical miles (18 km) long, between Wagoner and Potaka Inlets on the north side of Thurston Island. It was delineated from aerial photographs taken by U.S. Navy Operation Highjump in ...

Glacier Bight Glacier Bight is an open embayment about wide, indenting the north coast of Thurston Island between Hughes Peninsula and Noville Peninsula. It was first delineated from air photos taken by U.S. Navy Operation Highjump in December 1946, and was ...

is to the east, and just north off the coast from them are the hazardous

Porters Pinnacles Porters Pinnacles is a group of low ice-covered rocks forming a menace to navigation along the north coast of Thurston Island, located about 4 nautical miles (7 km) north of the east extremity of Glacier Bight. It was discovered by the U.S. ...

. East of Starr Peninsula are

Potaka Inlet Potaka Inlet is a narrow ice-filled inlet about 8 nautical miles (15 km) long, indenting the north side of Thurston Island immediately east of Starr Peninsula. It was first delineated from air photos taken by U.S. Navy Operation Highjump i ...

, Kearns Peninsula, followed by Peale Inlet. The larger

is to the east. It is bordered by

Murphy Inlet Murphy Inlet is an ice-filled inlet about 18 nautical miles (33 km) long, with two parallel branches at the head, lying between Noville and Edwards Peninsulas on the north side of Thurston Island, Antarctica. It was delineated from aer ...

, whose southern end is split into two prongs by Linsley Peninsula and

Ball Peninsula Ball Peninsula () is a broad ice-covered peninsula on the north side of Thurston Island, Antarctica. It extends into Murphy Inlet between Noville Peninsula and Edwards Peninsula. It was named by the Advisory Committee on Antarctic Names afte ...

Edwards Peninsula Edwards Peninsula is an ice-covered peninsula about long, between Murphy Inlet and Koether Inlet on the north side of Thurston Island. It was delineated from aerial photographs made by U.S. Navy Operation HIGHJUMP in December 1946 and by U.S ...

, Koether Inlet, and the larger

Evans Peninsula Evans Peninsula () is an ice-covered peninsula about long, between Koether Inlet and Cadwalader Inlet in the northeast part of Thurston Island. Cape Braathen is an ice-covered cape at the northwest termination of Evans Peninsula. It was di ...

are to the east.

Cadwalader Inlet Cadwalader Inlet is an ice-filled inlet about long, indenting the northeast coast of Thurston Island between Evans Peninsula and Lofgren Peninsula. It was discovered on helicopter flights from the USS ''Burton Island'' and USS ''Glacier'' b ...

Lofgren Peninsula Lofgren Peninsula () is an ice-covered peninsula about long, projecting between Cadwalader Inlet and Morgan Inlet on the northeast side of Thurston Island, Antarctica. The northern extremity of the peninsula is Cape Menzel, a bold rock cape. Th ...

, and

Morgan Inlet Morgan Inlet is an ice-filled inlet about long, with two branches, indenting the east end of Thurston Island, Antarctica, between Lofgren Peninsula and Tierney Peninsula. The south side of the larger north arm of the inlet is an area of icy ...

form the northeastern coast.

East coast

The easternmost point of the island is

, southeast of which is

Seraph Bay Seraph Bay is an open bay about 15 nautical miles (28 km) wide, formed at the southeast end of Thurston Island. It is bounded by Cape Annawan on the northwest, Abbot Ice Shelf on the southwest and Dustin Island on the southeast. It was ...

. Simpson Bluff, a broad ice-covered bluff, sits between

Levko Glacier Levko Glacier () is a glacier flowing from Pallid Crest to the eastern end of Thurston Island, Antarctica. It enters Seraph Bay between Tierney Peninsula and Simpson Bluff. The glacier was named by the Advisory Committee on Antarctic Names aft ...

and Savage Glacier where they enter the bay. Nearby Baker Knob is a small rounded coastal elevation which has an abrupt east face. Both Simpson Bluff and Baker Knob were named by the

Advisory Committee on Antarctic Names The Advisory Committee on Antarctic Names (ACAN or US-ACAN) is an advisory committee of the United States Board on Geographic Names responsible for recommending commemorative names for features in Antarctica. History The committee was established ...

(US-ACAN) for personnel from the Eastern Group of U.S. Navy Operation HIGHJUMP: Photographer's Mates R.M. Simpson and T.W. Baker, respectively. Operation HIGHJUMP obtained aerial photographs of Thurston Island and adjacent coastal areas in 1946-47. Snow-covered Harrison Nunatak stands south of

Savage Glacier Savage Glacier () is a glacier at the east end of Thurston Island, lying south of Tierney Peninsula and flowing east to Seraph Bay. The glacier was discovered on helicopter flights from the ''USS Glacier'' and Burton Island by personnel of the ...

. It was discovered on helicopter flights from the USS ''Burton Island'' (AGB-1) and USS ''Glacier'' (AGB-4) during the U.S. Navy

Expedition in February 1960, and was named by US-ACAN for Henry T. Harrison Jr., a U.S. Weather Bureau meteorologist with the

Byrd Antarctic Expedition Richard Evelyn Byrd Jr. (October 25, 1888 – March 11, 1957) was an American naval officer and explorer. He was a recipient of the Medal of Honor, the highest honor for valor given by the United States, and was a pioneering American aviator, p ...

in 1928–30. The southeast point of the island is Cape Walker.

South coast

On the south side of the island are King Peninsula, Williamson Peninsula, Evans Point, and Von der Wall Point, projecting into

. Williamson Peninsula is bordered by Schwartz Cove and O'Dowd Cove. Shelton Head is a

headland A headland, also known as a head, is a coastal landform, a point of land usually high and often with a sheer drop, that extends into a body of water. It is a type of promontory. A headland of considerable size often is called a cape.Whittow, John ...

marked by exposed rock, located west of Long Glacier on the south coast of Thurston Island. It was mapped by the

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

(USGS) from surveys and U.S. Navy air photos, 1960–66, and named by US-ACAN for John A. Shelton meteorologist at

Byrd Station The Byrd Station is a former research station established by the United States during the International Geophysical Year by U.S. Navy Seabees during Operation Deep Freeze II in West Antarctica. History A joint Army, Navy, Air Force, and Marin ...

, 1963-64. Prickly Ridge is a rounded ice-covered ridge west of Shelton Head on the south side of Thurston Island. The descriptive name was given by the

(US-ACAN); small dispersed

nunatak A nunatak (from Inuit ''nunataq'') is the summit or ridge of a mountain that protrudes from an ice field or glacier that otherwise covers most of the mountain or ridge. They are also called glacial islands. Examples are natural pyramidal peaks. ...

s rise above the ice surface, giving the feature a prickly appearance. Belknap Nunatak, an ice-covered spur, is the largest outcrop on the ridge. It was mapped by the USGS from surveys and from

U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage o ...

air photos, 1960–66, and named by US-ACAN for William Belknap, a field assistant at

, 1964–65.

References

{{Authority control Islands of Ellsworth Land