Candlemas Island

Candlemas Island

Satellite image
Geography
Location	57°05′S 26°40′W
Highest elevation	550 m (1800 ft)
Highest point	Mount Andromeda
Administration
United Kingdom
Demographics
Population	Uninhabtited

Candlemas Island (Spanish: Isla Candelaria) is a small uninhabited island of the Candlemas Islands in the South Sandwich Islands. It lies about 2 miles (3.2 km) from Vindication Island, separated by the Nelson Channel.

On the northwest flank of the island is an active stratovolcano, Lucifer Hill, that showed signs of activity in 1911 and glowing lava flows during 1953–1954. Mount Andromeda and Mount Perseus are both glacier-covered peaks on the island. Mount Andromeda is the island's highest point, with an elevation of 550 metres (1,804 ft).

Geography and geomorphology

Candlemas Island is one of the South Sandwich Islands, a 320 kilometres (200 mi) long north-south island arc to the southeast of South Georgia and the Falklands. They include Zavodovski, Leskov Island, Visokoi, Candlemas and Vindication Island, Saunders Island, Montagu Island, Bristol Island and Freezland Rock, Bellingshausen Island, Cook Island and Thule Island. All the islands are small and volcanic, most showing evidence of activity during the last two centuries. They are subject to intense marine erosion. Submarine volcanoes including Protector Shoals at the northern and Nelson and Kemp seamounts at the southern end of the island chain.

The island is also known as Lichtmess-Insel and Candelaria. It is rarely visited owing to the hostile weather and sea conditions, and the south and southeast coasts are hardly accessible, although tourist vessels occasionally land on Candlemas. Politically, together with South Georgia and the other South Sandwich Islands it forms the UK Overseas Territory of South Georgia and the South Sandwich Islands. In 2012, a marine protected area was established in the South Sandwich Islands. The scope of the protected area was further expanded in 2019.

With dimensions of 6 by 4 kilometres (3.7 mi × 2.5 mi), Candlemas is the third-largest of the South Sandwich Islands and consists of a southeastern, roughly square-shaped half and an irregularly shaped northwestern half. Visokoi lies 42 kilometres (26 mi) north and Saunders 76 kilometres (47 mi) south of Candlemas Island. Vindication Island is separated from Candlemas by the shallow (24 metres (79 ft)-27 metres (89 ft)) 3.7 kilometres (2.3 mi) wide Nelson Channel.

The northwestern half consists of a complex of scoria cones named Lucifer Hill (also known as Lucifer Hills), which reach a maximum elevation of 232 metres (761 ft), 229 metres (751 ft) or 140 metres (460 ft). Two main craters with depths of about 15 metres (49 ft) and diameters of 137 metres (449 ft) flank the main summit, which has a flat top. A subsidiary crater lies on the southwestern flank. They are surrounded by five lava flows, the eastern of which is old and covered with volcanic ash while the northern one is younger, with an irregular surface featuring blocks, ridges and gullies. The lava flows are morphologically aa lavas. The eastern lava flow forms Breakbones Plateau, while a northwestward extending lava flow constitutes the Vulcan Point peninsula. The southwestward and northwestward extending lava flows enclose the Tow Bay; Cauldron Pool lies just east of Tow Bay. Another unnamed pool lies at the end of Clinker Gulch on Lucifer Hill, and there are freshwater pools throughout the island. The coastline is formed by cliffs, with recesses and bays interspersed.

The southeastern half is the larger and consists of an extinct and eroded stratovolcano. It has two summits, the northeastern 455 metres (1,493 ft) high Mount Perseus and the southeastern Mount Andromeda; the latter is the highest point of Candlemas with 550 metres (1,800 ft) or 557 metres (1,827 ft) elevation and forms a north-south trending ridge with Mount Perseus. This half is asymmetric, rising from west to east, which may indicate that it is the remnant of a formerly larger volcano that was centered east of the current island. Glaciers cover most of the southeastern half of Candlemas and reach thicknesses of 23 metres (75 ft) in coastal cliff exposures. About 40% of Candlemas is ice-covered, reaching down to the sea on the southern and eastern side and in the north forming glacial tongues at elevations of 120 metres (390 ft). The glaciers have left a belt of moraines around the ice edge. Streams have incised glacial deposits and during summer carry meltwater. Cliffs with heights of 30–300 metres (98–984 ft) form most of its southern and eastern coasts, while a 18 metres (59 ft) wide youthful coastal terrace makes up the western and northern side. Marine deposits have formed the northward extending Demon Point peninsula, which encloses Kraken Bay between the peninsula and Lucifer Hill. Shrove Point is the southeastern end of Candlemas Island, while Boot Rock juts out from the eastern coastline and Clapmatch and Carbon Points. 750 metres (2,460 ft) east of the coastline is Tomblin Point.

Between the two halves lies Chimaera Flats, a southwest-northeast trending sandy plain which features two lagoons named Gorgon Pool and Medusa Pool. This flat area formed where the two halves of Candlemas Island shield the terrain from marine erosion, thus allowing the builtup of spits formed by boulders and shingles. Medusa Pool is the southwestern lagoon and was connected to the sea at Sea Serpent Cove in 1964, while Gorgon Pool is the northeastern one. The configuration of Chimaera Flats is variable over time, during 1830-1927 Candlemas Island was sometimes reported to consist of three islands although visual conditions can lead to Candlemas Island being mistaken for two islands.

Submarine structure

Around the islands the sea is less than 100 metres (330 ft) deep, forming a 12 kilometres (7.5 mi) wide shallow platform that is dotted by remnants of eroded islands such as Buddha Rock, Castor Rock, Cook Rock, Pollux Rock, Santa Rock, Saw Rock, Tomblin Rock and Trousers Rock especially around Vindication. Some of these rocks make up a series of shoals between the islands. The shelf itself probably formed through marine erosion and scouring by icebergs. East of Candlemas and abutting its southeastern side is a large 16 kilometres (9.9 mi) wide submarine embayment, probably the remnant of a large sector collapse.

Both Candlemas and Vindication rise from the same submarine volcano, and are named the Candlemas Island group. The volcano has a base diameter of more than 53 kilometres (33 mi) at 2,500 metres (8,200 ft) and a total volume of about 2,200 cubic kilometres (530 cu mi). Smaller ridges emanate from the submarine volcano and are interpreted as parts of it, while chutes emanating in all directions formed through mass wasting. A submarine ridge at 1 kilometre (0.62 mi) depth connects the group to Visokoi farther north.

Geology

East of the South Sandwich Islands, the South America Plate subducts beneath the Sandwich Plate at a rate of 67–79 millimetres per year (2.6–3.1 in/year) in the South Sandwich Trench. The South Sandwich Trench reaches depths of more than 7,000 metres (23,000 ft). The volcanic arc consists of volcanoes with heights of 3 kilometres (1.9 mi) that developed on top of the Sandwich Plate, which forms at the East Scotia Ridge farther west. Both the underlying oceanic crust (8-10 million years old) and the volcanic arc appear to be young; this may explain the peculiar basalt-rich composition and small size of the volcanoes.

Composition

Volcanic rocks from Candlemas consist of basalt, basaltic andesite, andesite and dacite, defining a calc-alkaline suite. Phenocrysts include feldspar, olivine, plagioclase and pyroxene, and there are gabbro-like xenoliths, but unlike other South Sandwich volcanoes the lavas are mostly aphyric. Rocks from the older southeastern half are mostly basaltic, the younger northwestern half is mostly andesitic/ dacitic. Some rocks have been weathered. Sulfur has accumulated around active fumaroles.

The basalt, which forms about 90% of all Candlemas rocks, is considered to be the primary rock, from which the andesites evolved through fractional crystallization.

Eruption history

No radiometric dating has been performed on Candlemas Island rocks, but the island appears to have formed in two stages. During the first stage, the southeastern half of the island formed, which today constitutes about 90% of the volume of Candlemas. Outcrops in cliffs of the southeastern half of the island feature alternating layers of porphyritic lava flows and scoria, which are intruded by dykes and sills and show evidence of later deformation. Apart from the lava flows, some deposits were originally emplaced in now-dry lagoons, others formed through fallout. Close to Medusa Pool, some lava flows have become palagonitic. Later in the history of the island, two lava flows were emplaced on the southwestern end of the southeastern half of Candlemas; one forms Clapmatch Point and may be analogous to historical eruptions at Tristan da Cunha. The southeastern half of the island was extensively eroded by the sea and by glaciers.

Later, there was a hiatus in activity, after which volcanism shifted north of the previous volcanic centre, forming Lucifer Hill in what were initially eruptions in shallow water. Lucifer Hill consists mostly of volcanic ash mixed with scoria, with blocks reaching sizes of 15 centimetres (5.9 in). The oldest outcrops belong to the northern cone and are found in Clinker Gulch. The cones emitted numerous lava flows reaching thicknesses of 15–46 metres (49–151 ft), separated by scoria and ash eruptions. Lava flows are thick and fragmented, with surface ridges. The relative ages of the lava flows have been established from their appearance and relative grade of erosion; two southern and northern flows formed first. Then the entire eastern half of the lava flow field was emplaced. Subsequently, the southwestern lava flow was erupted from the southern vent. Last, the northwestern lava flow and lava flows on the southeastern flank were emplaced. The lava flows form 1 kilometre (0.62 mi) wide lava deltas. Lucifer Hill was probably a separate island before it was joined to the older part of Candlemas Island.

Chronology and historical reports

Unlike the first stage, which may have lasted for 1-2 million years, the second stage probably only began a few centuries or millennia ago, which might make it one of the youngest volcanoes of the South Sandwich Islands. There is no evidence of recent activity in the southeastern half of the island, other than a localized tilting in its northwestern sector that may be caused by the activity of northwestern Candlemas. A 6,000 years old tephra layer in the Vostok and South Pole ice cores has been tentatively attributed to a large explosive eruption at Candlemas, which would have spread ash over a distance of 4,000 kilometres (2,500 mi). The Global Volcanism Program cites a 1250 BCE eruption recorded in ice cores, most likely from Candlemas.

Owing to their remote location, volcanic activity in the South Sandwich Islands is poorly documented. No eruptions have been directly observed at Candlemas. Steam and dark clouds were reported in 1823 and 1911. Some discrepancies between maps may indicate activity since 1930. Glowing lava fields were observed from the RRS John Biscoe in 1953-1954 on the northern side of Candlemas, and steam emission indicates that the northern lava flow may have been emplaced during this eruption, but it is not clear which lava flow, and the 1953-1954 report was considered questionable by LeMasurier et al. 1990.

Fumaroles

Lucifer Hill is fumarolically active, emitting steam and sulfurous gases. Gas emissions are concentrated in its two craters and at various fumaroles on its lower slopes. One fumarole in 2020 had a temperature of 96 °C (205 °F). Carbon dioxide is the principal non-water gas emitted by the fumaroles; sulfur species are dominated by hydrogen sulfide. Temperatures underground reach 50 centimetres (20 in); the volcanic warmth keeps Lucifer Hill ice-free and the heat signature has been observed from space by satellites.

Vent locations change over time, with a survey in 1997 noting a decline of fumarolic activity and vegetation shifts associated with changes in the fumarolic vents. In 1962, a geyser was observed at Cauldron Pool; in 1964 the geyser was gone but water temperatures in the pool exceeded 31 °C (88 °F) in many locations, with the pool itself steaming.

Climate

The South Sandwich Islands feature an oceanic climate with sparse sunshine, low seasonal temperature variation and temperatures only a few degrees above freezing most of the year. The skies on Candlemas Island are usually overcast, and strong westerly winds blow. The winds mobilize glacial dust and volcanic deposits. Fog is common. Between June and November the sea surrounding the islands is covered with sea ice. Icebergs occur around Candlemas and occasionally run aground in shallow waters.

Life

Plant cover is most widespread on Breakbones Plateau and at the edge of the ice cap. Most of the vegetation grows around fumaroles, where it forms communities consisting of hepatics, liverworts and mosses with a distinct structuration that can extend to 20 metres (66 ft) width. Fumaroles provide water through condensation of steam, supporting life. Similar but less well-developed communities grow on cold terrain, where various forms of lichens predominate. Moss patches grow around active and inactive fumaroles, and on lava soils. The ground temperatures where mosses grow range between 85 °C (185 °F) and 0 °C (32 °F). Peat deposits reach thicknesses of 20 centimetres (7.9 in) in some localities. Snow algae have been recorded, and algae grow inside of fumarolic vents and in bird colonies. Basidiomycetes fungi grow among the plants. One higher plant, the Antarctic hair grass, has been reported from fumarolic terrain and its occurrence is restricted to these. The low temperatures and the high permeability of the ground restrict vegetation growth on most of the South Sandwich Islands, and trampling and faecal input from penguin colonies further limit vegetation development close to penguin colonies. The vegetation resembles that of Deception Island, another volcanic island around Antarctica.

Penguins, petrels and skuas visit the island, and there are penguin colonies at numerous sites along the coast. Large breeding populations with over a hundred members have been recorded for Adélie penguins, brown skuas, cape petrels, chinstrap penguins, gentoo penguins, macaroni penguins, snow petrels, southern fulmars, southern giant petrels (their main breeding site in the South Sandwich Islands) and Wilson's storm petrels, and black-bellied storm petrels have been observed breeding. Mammals include Antarctic fur seals, elephant seals, leopard seals and Weddel seals. Penguin populations appear to be stable on Candlemas Island. Finds of charred bones imply that penguin populations are sometimes impacted by volcanic activity. Small animals include mites, nematodes, rotifers, springtails and tardigrades. Brittle stars have been recovered from the shelf around Candlemas Island.

New species

The bacterium Bacillus fumarioli was discovered in soils on Candlemas Island, Mount Melbourne and Mount Rittmann. This wide dispersion may indicate that it is propagated by wind. Other species that were originally discovered on Candlemas Island are Bacillus shackletonii, which grew in soils on lava flows, Bacillus luciferensis, which was discovered in soils from Lucifer Hill and named after the site of discovery, Paenibacillus cineris and Paenibacillus cooki, both from soil around an active fumarole. The mite Calvolia antarctica was discovered in lichen-encrusted rocks of Candlemas Island.

Research history

Candlemas Island was discovered on the 2th of February 1775 (Candlemas Day) by James Cook from the HMS Resolution, but not visited. In the 19th century, visits were limited to sealers and whaling in the surrounding sea. During the 20th century scientific research and landings began, first C. A. Larsen in 1908 landed on Shrove Point at the southeastern end of Candlemas, then by the RRS Shackleton in January 1961 and the ice patrol ship HMS Protector in March 1962 and 1964. As a consequence of the 1964 visit, Candlemas Island is the best investigated of the South Sandwich Islands. Some of these investigations established temporary field camps on Candlemas Island. Sealing and whaling activities are largely undocumented, but archaeological evidence indicates that landing parties stayed on Candlemas for several weeks, and sealing activity may have led to the disappearance of Antarctic fur seals from the surroundings.

Other

Marine debris, mostly human in origin, has been found at Candlemas Island.

See also

• Breakbones Plateau
• List of Antarctic and sub-Antarctic islands
• List of volcanoes in South Sandwich Islands
• Tomblin Rock

References

Sources

• Baker, P. E.; Holdgate, M. W.; Longton, R. E.; Tilbrook, P. J.; Tomblin, J. F.; Vaughan, R. W.; Wynne-Edwards, C. J. C. (August 1964). "A Survey of the South Sandwich Islands". Nature. 203 (4946): 691–693. doi:10.1038/203691a0. ISSN 1476-4687.
• Convey, P.; Morton, A.; Poncet, J. (April 1999). "Survey of marine birds and mammals of the South Sandwich Islands". Polar Record. 35 (193): 107–124. doi:10.1017/S0032247400026450. ISSN 1475-3057.
• Convey, P.; Greenslade, P.; Pugh, P. J. A. (April 2000). "The terrestrial micro-arthropod fauna of the South Sandwich Islands". Journal of Natural History. 34 (4): 597–609. doi:10.1080/002229300299462.
• Convey, P.; Barnes, D.; Morton, A. (1 August 2002). "Debris accumulation on oceanic island shores of the Scotia Arc, Antarctica". Polar Biology. 25 (8): 612–617. doi:10.1007/s00300-002-0391-x. ISSN 1432-2056.
• Convey, P.; Lewis Smith, R. I.; Hodgson, D. A.; Peat, H. J. (November 2000). "The flora of the South Sandwich Islands, with particular reference to the influence of geothermal heating". Journal of Biogeography. 27 (6): 1279–1295. doi:10.1046/j.1365-2699.2000.00512.x.
• Fratt, D. B.; Dearborn, J. H. (1 August 1984). "Feeding biology of the Antarctic brittle star Ophionotus victoriae (Echinodermata: Ophiuroidea)". Polar Biology. 3 (3): 127–139. doi:10.1007/BF00442644. ISSN 1432-2056.
• "Candlemas Island". Global Volcanism Program. Smithsonian Institution. Retrieved 18 September 2023.
• Hart, Tom; Convey, Peter (18 June 2018). "The South Sandwich Islands – a community of meta-populations across all trophic levels". Biodiversity: 1–14. doi:10.1080/14888386.2018.1464952.
• Higashi, Akira; Fujii, Yoshiyuki (January 1994). "Studies on microparticles contained in medium-depth ice cores retrieved from east Dronning Maud Land, Antarctica". Annals of Glaciology. 20: 73–79. doi:10.3189/1994AoG20-1-73-79. ISSN 0260-3055.
• Holdgate, M. W. (January 1963). "Observations in the South Sandwich Islands, 1962". Polar Record. 11 (73): 394–405. doi:10.1017/S0032247400053511. ISSN 1475-3057.
• Holdgate, M.W.; Baker, P.E. (1979). "The South Sandwich Islands: I. General description" (PDF). British Antarctic Survey Scientific Reports. 91. Cambridge: British Antarctic Survey: 76.
• Hughes, A. M.; Tilbrook, P. J. (1966). "A new species of Calbolia (Acaridae, Acarina) from the South Sandwich Islands" (PDF). British Antarctic Survey Bulletin (10): 45–53.
• Kennedy, Andrew D. (1 July 1996). "Antarctic fellfield response to climate change: a tripartite synthesis of experimental data". Oecologia. 107 (2): 141–150. doi:10.1007/BF00327897. ISSN 1432-1939.
• Kornicker, S., ed. (1986). Biology of the Antarctic Seas XVII. Antarctic Research Series. Vol. 44. Washington, D. C.: American Geophysical Union. doi:10.1029/ar044. ISBN 978-0-87590-169-5.
• Kyle, P. R.; Palais, J.; Thomas, E. (1984). "The Vostok tephra: An important englacial stratigraphic marker?". Antarct. J. U. S. (19): 64–65.
• Leat, Philip T.; Tate, Alex J.; Tappin, David R.; Day, Simon J.; Owen, Matthew J. (September 2010). "Growth and mass wasting of volcanic centers in the northern South Sandwich arc, South Atlantic, revealed by new multibeam mapping". Marine Geology. 275 (1–4): 110–126. doi:10.1016/j.margeo.2010.05.001.
• LeMasurier, W.E.; Thomson, J.W.; Baker, P.E.; Kyle, P.R.; Rowley, P.D.; Smellie, J.L.; Verwoerd, W.J., eds. (1990). Volcanoes of the Antarctic Plate and Southern Oceans. Antarctic Research Series. Vol. 48. Washington, D. C.: American Geophysical Union. doi:10.1029/ar048. ISBN 978-0-87590-172-5.
• Liu, Emma J.; Wood, Kieran; Aiuppa, Alessandro; Giudice, Gaetano; Bitetto, Marcello; Fischer, Tobias P.; McCormick Kilbride, Brendan T.; Plank, Terry; Hart, Tom (11 December 2020). "Volcanic activity and gas emissions along the South Sandwich Arc". Bulletin of Volcanology. 83 (1): 3. doi:10.1007/s00445-020-01415-2. ISSN 1432-0819.
• Logan, N A; Lebbe, L; Hoste, B; Goris, J; Forsyth, G; Heyndrickx, M; Murray, B L; Syme, N; Wynn-Williams, D D; De Vos, P (1 September 2000). "Aerobic endospore-forming bacteria from geothermal environments in northern Victoria Land, Antarctica, and Candlemas Island, South Sandwich archipelago, with the proposal of Bacillus fumarioli sp. nov". International Journal of Systematic and Evolutionary Microbiology. 50 (5): 1741–1753. doi:10.1099/00207713-50-5-1741.
• Logan, Niall A; Lebbe, Liesbeth; Verhelst, An; Goris, Johan; Forsyth, Gillian; Rodriguez-Diaz, Marina; Heyndrickx, Marc; De Vos, Paul (2002). "Bacillus luciferensis sp. nov., from volcanic soil on Candlemas Island, South Sandwich archipelago". International Journal of Systematic and Evolutionary Microbiology. 52 (6): 1985–1989. doi:10.1099/00207713-52-6-1985. ISSN 1466-5034.
• Logan, Niall A.; De Clerck, Elke; Lebbe, Liesbeth; Verhelst, An; Goris, Johan; Forsyth, Gillian; Rodríguez-Díaz, Marina; Heyndrickx, Marc; De Vos, Paul (2004). "Paenibacillus cineris sp. nov. and Paenibacillus cookii sp. nov., from Antarctic volcanic soils and a gelatin-processing plant". International Journal of Systematic and Evolutionary Microbiology. 54 (4): 1071–1076. doi:10.1099/ijs.0.02967-0. ISSN 1466-5034.
• Logan, Niall A.; Lebbe, Liesbeth; Verhelst, An; Goris, Johan; Forsyth, Gillian; Rodríguez-Díaz, Marina; Heyndrickx, Marc; De Vos, Paul (2004). "Bacillus shackletonii sp. nov., from volcanic soil on Candlemas Island, South Sandwich archipelago". International Journal of Systematic and Evolutionary Microbiology. 54 (2): 373–376. doi:10.1099/ijs.0.02661-0. ISSN 1466-5034.
• Longton, R. E.; Holdgate, M. W. (1967). "Temperature Relationships of Antarctic Vegetation". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. 252 (777): 237–250. ISSN 0080-4622.
• Longton, R.E.; Holdgate, M.W. (1979). "The South Sandwich Islands: IV. Botany" (PDF). British Antarctic Survey Scientific Reports. 94. Cambridge: British Antarctic Survey: 53.
• Lynch, Heather J.; White, Richard; Naveen, Ron; Black, Andy; Meixler, Marcia S.; Fagan, William F. (1 September 2016). "In stark contrast to widespread declines along the Scotia Arc, a survey of the South Sandwich Islands finds a robust seabird community". Polar Biology. 39 (9): 1615–1625. doi:10.1007/s00300-015-1886-6. ISSN 1432-2056.
• Palais, J. M.; Kyle, P. R.; Mosley-Thompson, E.; Thomas, E. (August 1987). "Correlation of a 3,200 year old tephra in ice cores from Vostok and South Pole Stations, Antarctica". Geophysical Research Letters. 14 (8): 804–807. doi:10.1029/GL014i008p00804.
• Tomblin, J.F. (1979). "The South Sandwich Islands: II. The geology of Candlemas Island" (PDF). British Antarctic Survey Scientific Reports, 92. Cambridge: British Antarctic Survey: 33.

External links

• List of hepatics