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

. It lies in the

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 ...

west of

Palmer Land Palmer Land () is the portion of the Antarctic Peninsula, Antarctica that lies south of a line joining Cape Jeremy and Cape Agassiz. This application of Palmer Land is consistent with the 1964 agreement between the Advisory Committee on Antarctic N ...

Antarctic Peninsula The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martin in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctica. ...

from which it is separated by

Marguerite Bay Marguerite Bay or Margaret Bay is an extensive bay on the west side of the Antarctic Peninsula, which is bounded on the north by Adelaide Island and on the south by Wordie Ice Shelf, George VI Sound and Alexander Island. The mainland coast on th ...

and

George VI Sound George VI Sound or Canal Jorge VI or Canal Presidente Sarmiento or Canal Seaver or King George VI Sound or King George the Sixth Sound is a major bay/ fault depression, 300 miles (483 km) long and mainly covered by a permanent ice shelf. I ...

. The George VI Ice Shelf entirely fills George VI Sound and connects Alexander Island to Palmer Land. The island partly surrounds

Wilkins Sound Wilkins Sound is a seaway in Antarctica that is largely occupied by the Wilkins Ice Shelf. It is located on the southwest side of the Antarctic Peninsula between the concave western coastline of Alexander Island and the shores of Charcot Islan ...

, which lies to its west.Stewart, J. (2011) ''Antarctic An Encyclopedia'' McFarland & Company Inc, New York. 1776 pp. . Alexander Island is about long in a north–south direction, wide in the north, and wide in the south. Alexander Island is the second-largest uninhabited island in the world, after

Devon Island Devon Island (, ) is an island in Canada and the largest desert island, uninhabited island (no permanent residents) in the world. It is located in Baffin Bay, Qikiqtaaluk Region, Nunavut, Canada. It is one of the largest members of the Arctic Ar ...

History

Alexander Island was discovered on January 28, 1821, by a Russian expedition under

Fabian Gottlieb von Bellingshausen Faddey Faddeyevich Bellingshausen or Fabian Gottlieb Benjamin von Bellingshausen ( – ) was a Russian cartographer, explorer, and naval officer of Baltic German descent, who attained the rank of admiral. He participated in the first Russi ...

, who named it Alexander I Land for the reigning

Tsar Tsar (; also spelled ''czar'', ''tzar'', or ''csar''; ; ; sr-Cyrl-Latn, цар, car) is a title historically used by Slavic monarchs. The term is derived from the Latin word '' caesar'', which was intended to mean ''emperor'' in the Euro ...

Alexander I of Russia Alexander I (, ; – ), nicknamed "the Blessed", was Emperor of Russia from 1801, the first king of Congress Poland from 1815, and the grand duke of Finland from 1809 to his death in 1825. He ruled Russian Empire, Russia during the chaotic perio ...

. What, in fact, is an island, was believed to be part of the Antarctic mainland until 1940. Its insular nature was proven in December 1940, by a two-person

sledge A sled, skid, sledge, or sleigh is a land vehicle that slides across a surface, usually of ice or snow. It is built with either a smooth underside or a separate body supported by two or more smooth, relatively narrow, longitudinal runners ...

party composed of

Finn Ronne Finn Ronne (December 20, 1899 – January 12, 1980) was a Norwegian-born U.S. citizen and Antarctic explorer. Background Finn Ronne was born in Horten, in Vestfold county, Norway. His father, Martin Rønne (1861–1932), was a polar explorer ...

and

Carl Eklund Carl Robert Eklund (January 27, 1909 – November 3, 1962) was a leading American specialist in ornithology and geographic research in both the north and south polar regions. He was appointed as the first Scientific Station Leader of the Wilkes S ...

of the

United States Antarctic Service The United States Antarctic Program (or USAP; formerly known as the United States Antarctic Research Program or USARP and the United States Antarctic Service or USAS) is an organization of the United States government which has a presence in the ...

. In the 1950s, a British base administered as part of the

British Antarctic Territory The British Antarctic Territory (BAT) is a sector of Antarctica claimed by the United Kingdom as one of its 14 British Overseas Territories, of which it is by far the largest by area. It comprises the region south of 60°S latitude and betwee ...

was constructed as

Fossil Bluff Fossil Bluff is a seasonal British aircraft refuelling station located on the east coast of Alexander Island in Antarctica. In operation since 1961, its facilities provide fuel, storage, and ancillary support for British exploration and operation ...

(''Base KG''). The island was claimed by the United Kingdom in 1908 as part of the

. Territorial claims have also been set by both

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

(in 1940) and

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

(in 1942). Currently, under the

Antarctic Treaty The Antarctic (, ; commonly ) is the polar region of Earth that surrounds the South Pole, lying within the Antarctic Circle. It is diametrically opposite of the Arctic region around the North Pole. The Antarctic comprises the continent of A ...

no claim has been officially recognized. The island contains the British

meteorological Meteorology is the scientific study of the Earth's atmosphere and short-term atmospheric phenomena (i.e. weather), with a focus on weather forecasting. It has applications in the military, aviation, energy production, transport, agriculture ...

centre and refuelling base.

Geography

The surface of Alexander Island is predominantly ice-covered. There exist some exposed

nunatak A nunatak (from Inuit language, Inuit ) 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 often form natural pyramidal peaks. Isolated nunataks are also cal ...

s and a few ice-free areas of significant size, including Ablation Point Massif. The nunataks are the peaks of north–south trending mountain ranges and hills. They include the Colbert, Havre,

Lassus Orlando di Lasso ( various other names; probably – 14 June 1594) was a composer of the late Renaissance. The chief representative of the mature polyphonic style in the Franco-Flemish school, Lassus stands with William Byrd, Giovanni Pierlu ...

Rouen Rouen (, ; or ) is a city on the River Seine, in northwestern France. It is in the prefecture of Regions of France, region of Normandy (administrative region), Normandy and the Departments of France, department of Seine-Maritime. Formerly one ...

Sofia University Sofia University "St. Kliment Ohridski" () is a public university, public research university in Sofia, Bulgaria. It is the oldest institution of higher education in Bulgaria. Founded on 1 October 1888, the edifice of the university was constr ...

, and

Walton Mountains Walton Mountains is an isolated chain of three predominantly snow-covered mountain masses, rising to about 1,450 m at Mount McArthur, extending south from Schubert Inlet for 25 miles (40 km) in central Alexander Island, Antarctica. The mou ...

, the

Staccato Peaks Staccato Peaks () is a series of rock peaks extending 11 miles (18 km) in a north–south direction, rising to about 940 m with Hageman Peak being the highest peak of the Staccato Peaks, rising from the snowfields 20 miles (32 km) sou ...

, the Lully Foothills, the Finlandia Foothills, the

Elgar Uplands The Elgar Uplands () are uplands rising to , between Tufts Pass to the north and Sullivan Glacier to the south, in the northern part of Alexander Island, Antarctica. They were first photographed from the air and roughly mapped by the British Grah ...

, and the

Douglas Range The Douglas Range () is a sharp-crested mountain range, range, with peaks rising to 3,000 metres, extending 120 km (75 mi) in a northwest–southeast direction from Mount Nicholas to Mount Edred and forming a steep east escarpment of Al ...

. These mountains, peaks, hills, and uplands are surrounded by a permanent ice sheet, which consists of glaciers that flow off of Alexander Island. These glaciers flow west into the

Bach Johann Sebastian Bach (German: �joːhan zeˈbasti̯an baχ ( – 28 July 1750) was a German composer and musician of the late Baroque period. He is known for his prolific output across a variety of instruments and forms, including the or ...

and Wilkins Ice Shelves and Bellingshausen Sea, and east into the George VI Ice Shelf. The George VI Ice Shelf is fed by both by

outlet glacier Glacier morphology, or the form a glacier takes, is influenced by temperature, precipitation, topography, and other factors. The goal of glacial morphology is to gain a better understanding of glaciated landscapes and the way they are shaped. T ...

s from the ice cap on Palmer Land and Alexander Island. Another notable feature of Alexander Island is

Hodgson Lake Hodgson Lake is a perennially ice-covered freshwater lake, which is about 2 km (1.2 mi) long by about 1.5 km (0.93 mi) wide. It is located within the southern part of Alexander Island, west of Palmer Land in Antarctica, at app ...

, a former

subglacial lake A subglacial lake is a lake that is found under a glacier, typically beneath an ice cap or ice sheet. Subglacial lakes form at the boundary between ice and the underlying bedrock, where liquid water can exist above the lower melting point of ic ...

that has emerged from under an ice sheet that had covered it. Hodgson Lake is long by , and has a deep

water column The (oceanic) water column is a concept used in oceanography to describe the physical (temperature, salinity, light penetration) and chemical ( pH, dissolved oxygen, nutrient salts) characteristics of seawater at different depths for a defined ...

that lies sealed beneath a thick perennial lake ice. The northern side of Hodgson Lake is bounded by the Saturn Glacier, which flows east into George VI Sound, while the southern side of Hodgson Lake is bounded by the northern face of Citadel Bastion. During the

Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Last Glacial Coldest Period, was the most recent time during the Last Glacial Period where ice sheets were at their greatest extent between 26,000 and 20,000 years ago. Ice sheets covered m ...

, Hodgson Lake was covered by the ice sheet at least thick. This ice sheet started thinning about 13,500 years ago. It retreated and left Hodgson Lake covered by perennial ice sometime before 11,000 years ago. This lake has been covered by perennial ice since that time. Other features on the island include Damocles Point and Mount Tyrrell.

Brahms Inlet

Brahms Inlet () is an ice-filled

inlet An inlet is a typically long and narrow indentation of a shoreline such as a small arm, cove, 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 ...

, long and wide, indenting the north side of

Beethoven Peninsula The Beethoven Peninsula is a deeply indented, ice-covered peninsula, long in a northeast–southwest direction and wide at its broadest part, forming the southwest part of Alexander Island, which lies off the southwestern portion of the Antarct ...

on Alexander Island between Harris Peninsula and

Derocher Peninsula Derocher Peninsula () is a snow-covered peninsula between Brahms Inlet and Mendelssohn Inlet on the north side of Beethoven Peninsula, Alexander Island, Antarctica. It was photographed from the air by the Ronne Antarctic Research Expedition, 19 ...

, while the headland

Mazza Point Mazza Point () is a snow-covered headland lying between Brahms Inlet and Mendelssohn Inlet, marking the northwest end of Derocher Peninsula, a minor peninsula that extends to a northwest point from Beethoven Peninsula, situated in the southwest ...

lies immediately northeast of the inlet and Mount Grieg lies immediately southeast of the base of Brahms Inlet. It was observed from the air and first mapped by the

Ronne Antarctic Research Expedition The Ronne Antarctic Research Expedition (RARE) was an expedition from 1947–1948 which researched the area surrounding the head of the Weddell Sea in Antarctica. Background Finn Ronne led the RARE which was the final privately sponsored exp ...

(RARE), 1947–48, and re-mapped from the RARE air photos by Derek J.H. Searle of the

Falkland Islands Dependencies Survey The Falkland Islands and Dependencies Aerial Survey Expedition (FIDASE) was an aerial survey of the Falkland Islands Dependencies The Falkland Islands Dependencies was the constitutional arrangement from 1843 until 1985 for administering the v ...

in 1960. It was named by the

UK Antarctic Place-Names Committee The UK Antarctic Place-Names Committee (or UK-APC) is a United Kingdom government committee, part of the Foreign and Commonwealth Office, responsible for recommending names of geographical locations within the British Antarctic Territory (BAT) an ...

after

Johannes Brahms Johannes Brahms (; ; 7 May 1833 – 3 April 1897) was a German composer, virtuoso pianist, and conductor of the mid-Romantic period (music), Romantic period. His music is noted for its rhythmic vitality and freer treatment of dissonance, oft ...

, the German composer.

Harris Peninsula

Harris Peninsula () is a broad snow-covered

peninsula A peninsula is a landform that extends from a mainland and is only connected to land on one side. Peninsulas exist on each continent. The largest peninsula in the world is the Arabian Peninsula. Etymology The word ''peninsula'' derives , . T ...

surmounted by

Mount Lee Mount Lee is a peak in the Santa Monica Mountains, located in Griffith Park in Los Angeles, California, USA. The Hollywood Sign is located on its southern slope. History The original unnamed peak was one of the "three sisters" along wi ...

, between

Verdi Inlet Verdi Inlet () is an ice-filled inlet lying between Pesce Peninsula and Harris Peninsula, on the north side of the Beethoven Peninsula, situated in the southwest portion of Alexander Island, Antarctica. The inlet was observed from the air and fir ...

and Brahms Inlet on the north side of the

, located in the southwest portion of Alexander Island,

. It is one of eight peninsulas of Alexander Island. It was photographed from the air by the RARE, 1947–48, and mapped from these photographs by D. Searle of the

, 1960. It was 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 ...

for Commander Michael J. Harris,

U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Department of Defense. It is the world's most powerful navy with the largest displacement, at 4.5 million tons in 2021. It has the world's largest aircraft ...

Commanding Officer The commanding officer (CO) or commander, or sometimes, if the incumbent is a general officer, commanding general (CG), is the officer in command of a military unit. The commanding officer has ultimate authority over the unit, and is usually give ...

of Squadron

VXE-6 Antarctic Development Squadron Six (VXE-6 or ANTARCTIC DEVRON SIX, commonly referred to by its nickname, The Puckered Penguins) was a United States Navy air test and evaluation squadron based at Naval Air Station Point Mugu, California with for ...

, from May 1982 to May 1983.

Lyadov Glacier

Lyadov Glacier () is a glacier flowing east-northeast from Harris Peninsula, Alexander Island, into Brahms Inlet. It was named by the USSR Academy of Sciences in 1987 after

Anatoly Lyadov Anatoly Konstantinovich Lyadov (; ) was a Russian composer, teacher and conductor. Biography Lyadov was born in 1855 in St. Petersburg, Russian Empire, into a family of eminent Russian musicians. He was taught informally by his conductor s ...

(1855–1914), a Russian composer.

Geology

According to Hole, "The geology of Alexander Island can be attributed mainly to processes associated with the

subduction Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second p ...

of proto-Pacific

oceanic crust Oceanic crust is the uppermost layer of the oceanic portion of the tectonic plates. It is composed of the upper oceanic crust, with pillow lavas and a dike complex, and the lower oceanic crust, composed of troctolite, gabbro and ultramaf ...

along the western margin of the Antarctic Peninsula, from latest

Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

Late Tertiary The Neogene ( ,) is a Geologic time scale#Terminology, geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago (Year#Abbreviations yr and ya, Mya) to the beginning of the present Quatern ...

times." The LeMay Group

accretionary prism An accretionary wedge or accretionary prism forms from sediments accreted onto the non-subducting tectonic plate at a convergent plate boundary. Most of the material in the accretionary wedge consists of marine sediments scraped off from the do ...

complex, along with

plutonic Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form ''intrusions'', such as batholiths, dikes, sills, laccoliths, and volcanic necks.Intrusive RocksIntrusive rocks accessdate: Marc ...

and

volcanic A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often fo ...

rocks, are prevalent along the western portion of the island. The LeMay Group consists of variably-deformed and

metamorphosed Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causi ...

sedimentary and igneous rocks. Although it is dominated by deformed

arkosic Arkose () or arkosic sandstone is a detrital sedimentary rock, specifically a type of sandstone containing at least 25% feldspar. Arkosic sand is sand that is similarly rich in feldspar, and thus the potential precursor of arkose. Components ...

sedimentary rocks, it includes

turbiditic A turbidity current is most typically an underwater current of usually rapidly moving, sediment-laden water moving down a slope; although current research (2018) indicates that water-saturated sediment may be the primary actor in the process. ...

greywackes Greywacke or graywacke ( ) is a variety of sandstone generally characterized by its hardness (6–7 on Mohs scale), dark color, and poorly sorted angular grains of quartz, feldspar, and small rock fragments or sand-size lithic fragments set i ...

, black mudstones, and conglomerates. The thick

Upper Jurassic The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the name ...

Lower Cretaceous Lower may refer to: * ''Lower'' (album), 2025 album by Benjamin Booker * Lower (surname) * Lower Township, New Jersey *Lower Receiver (firearms) * Lower Wick Gloucestershire, England See also * Nizhny {{Disambiguation ...

Fossil Bluff Group sedimentary rocks

outcrop An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth and other terrestrial planets. Features Outcrops do not cover the majority of the Earth's land surface because in most p ...

as a long by wide belt along the eastern coast. This Fossil Bluff Group consists of a basal deep-marine assemblage thick, overlain by a

mudstone Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from ''shale'' by its lack of fissility.Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York, ...

assemblage up to thick, followed by a shallow-marine assemblage of coarsening upward

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

Alkali basalt Alkali basalt or alkali olivine basalt is a dark-colored, porphyritic volcanic rock usually found in oceanic and continental areas associated with volcanic activity, such as oceanic islands, continental rifts and volcanic fields. Alkali basalt i ...

s erupted after the cessation of subduction. These range in age from the

tephrite Tephrite is an igneous, volcanic (extrusive) rock, with aphanitic to porphyritic texture. Mineral content is usually abundant feldspathoids (leucite or nepheline), plagioclase, and lesser alkali feldspar. Pyroxenes (clinopyroxenes) are common ...

s at Mount Pinafore (5.5–7.6 Ma), to the

basanite Basanite () is an igneous, volcanic ( extrusive) rock with aphanitic to porphyritic texture. It is composed mostly of feldspathoids, pyroxenes, olivine, and calcic plagioclase and forms from magma low in silica and enriched in alkali metal ox ...

s at

Rothschild Island Rothschild Island is a black rugged island long, mainly ice-covered but surmounted by prominent peaks of Desko Mountains in Antarctica, west of the north part of Alexander Island in the north entrance to Wilkins Sound. Geography and wildlife ...

(5.5 Ma) and Hornpipe Heights (2.5 Ma), to the alkali and

olivine basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron ( mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% ...

s on

(<1-2.5 Ma).Macdonald, D.I.M. and P.J. Butterworth (1990) "The stratigraphy, setting and hydrocarbon potential of the Mesozoic sedimentary basins of the Antarctic Peninsula." in B. John, ed., pp. 101–125. ''Antarctica as an exploration frontier; hydrocarbon potential, geology, and hazards''. AAPG Studies in Geology. vol. 31 American Association of Petroleum Geologists, Tulsa, Oklahoma. The LeMay Range Fault trends N-S, parallel to the

, and the Fossil Bluff Formation is downfaulted to the east of this fault against the LeMay Group. Sand dykes are found against this fault zone and in many other parts of the Fossil Bay Formation. Fossils within the Fossil Bluff Formation include

ammonite Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...

belemnite Belemnitida (or belemnites) is an extinct order (biology), order of squid-like cephalopods that existed from the Late Triassic to Late Cretaceous (And possibly the Eocene). Unlike squid, belemnites had an internal skeleton that made up the cone ...

bivalve Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

s, and

serpulid The Serpulidae are a family of sessile, tube-building annelid worms in the class Polychaeta. The members of this family differ from other sabellid tube worms in that they have a specialized operculum that blocks the entrance of their tubes wh ...

References

* * * {{Authority control Chilean Antarctic Territory Argentine Antarctica British Antarctic Territory Bulgaria and the Antarctic Islands of Palmer Land