Murray Hill is the highest point of

Christmas Island Christmas Island, officially the Territory of Christmas Island, is an Australian external territory comprising the island of the same name. It is located in the Indian Ocean, around south of Java and Sumatra and around north-west of the ...

, at above sea level. It was first scaled in 1857 even though the island had been located in 1615. The plateau around the summit is dense and evergreen, although the biodiversity of trees is limited compared to similar areas of continental rainforest. Murray Hill is an integral part of the

Christmas Island National Park Christmas Island National Park is a national park occupying most of Christmas Island, an Australian territory in the Indian Ocean southwest of Indonesia. The park is home to many species of animal and plant life, including the eponymous red c ...

covering an area of of the island's southwest corner; the island's total area is approximately .

History

Christmas Island was first discovered on in 1615 by Captain John Milward of the

East India Company The East India Company (EIC) was an English, and later British, joint-stock company founded in 1600 and dissolved in 1874. It was formed to trade in the Indian Ocean region, initially with the East Indies (the Indian subcontinent and South ...

ship, and it was named Christmas Island on 25 December 1643. However, it was only 272 years later, in 1887, that detailed exploration of the topographical features and geological formations of the island was performed. This was an effort by a small group of people from HMS ''Egeria''. They were the first to scale the highest mountain of the island, which is named as Murray Hill, though in earlier centuries some hills closer to the coast line and dense forest areas had been discovered. The detailed exploration also led to the finding of pure

phosphate In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid . The phosphate or orthophosphate ion is derived from phosph ...

lime Lime commonly refers to: * Lime (fruit), a green citrus fruit * Lime (material), inorganic materials containing calcium, usually calcium oxide or calcium hydroxide * Lime (color), a color between yellow and green Lime may also refer to: Botany ...

which ensured the development of the island in the next century. Its control initially came under the

British Dominion The term ''Dominion'' is used to refer to one of several self-governing nations of the British Empire. "Dominion status" was first accorded to Canada, Australia, New Zealand, Newfoundland, South Africa, and the Irish Free State at the 1926 Im ...

(from 1888), then as the British Colony of

Singapore Singapore (), officially the Republic of Singapore, is a sovereign island country and city-state in maritime Southeast Asia. It lies about one degree of latitude () north of the equator, off the southern tip of the Malay Peninsula, bor ...

(after

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

), and finally as a sovereign part of Australia from 1 October 1958.

Geography and geology

In the saddle-shaped Christmas Island, the Murray Hill rises to a height of . It is situated in the western central part of the island. It is to the southeast of Northwest Point where the Headridge Hill rises to a height of . West White Beach occurs on the southwest side of the hill. At in width, the most narrow point of Christmas Island is a line drawn north–south through Murray Hill. The entire island including Murray Hill has been formed out of submarine mountain formations. It is conjectured to be an ancient

atoll An atoll () is a ring-shaped island, including a coral rim that encircles a lagoon partially or completely. There may be coral islands or cays on the rim. Atolls are located in warm tropical or subtropical oceans and seas where corals can gr ...

, with lime formation dominating the terrain, with phosphates of alumina and iron recorded on the hills. The entire island is geologically identified as an isolated limestone-capped volcanic island with hill formations rising to a height of above the sea floor. Geological formations recorded are mainly-basaltic volcanic rocks interspersed with tertiary limestones and occasional inter-bedded

volcanic A volcano is a rupture 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 found where tectonic plates a ...

s overlaid by phosphate-rich soils on the surface in some areas. Along with the highest elevations of Phosphate Hill and Flying Fish Cove, the rocks from Murray Hill summit are characterized as dolomitic limestones, containing between 34 and 41 percent carbonate of magnesia. Analyses of the rocks has shown that the fossils are mostly obliterated, though there are remains of

foraminifera Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular ectoplasm for catching food and other uses; and commonly ...

, ''

Lithothamnion ''Lithothamnion'' is a genus of thalloid red alga comprising 103 species. Its members are known by a number of common names.Recorded common names are griuán, maërl, punalevä-suku, stenhinna and maerl. The monomerous, crustose thalli are compos ...

'', and possibly

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and ...

. The small, brown spherules of phosphatic matter which occur on the hill in a bed of rock may be explained because of

phosphatic fossilization Phosphatic fossilization has occurred in unusual circumstances to preserve some extremely high-resolution microfossils in which careful preparation can even reveal preserved cellular structures. Such microscopic fossils are only visible under the s ...

of volcanic rock. Murray Hill has an

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

of many rocks subject to

weathering Weathering is the deterioration of rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little or no movement) ...

. Recent ⁴⁰Ar/³⁹Ar geochronology study by Taneja et al. (2015) on the volcanic rocks from Christmas Island have shown that the experienced a renewed volcanism in the Eocene (43 - 37 Ma) and then a minor phase of volcanism in the Pliocene (4.2 Ma).

Ecology

The plateau around the summit is dense and evergreen, although the biodiversity of trees is limited compared to similar areas of continental rainforest. One of the main fauna is the red land crab, ''

Gecarcoidea natalis The Christmas Island red crab (''Gecarcoidea natalis'') is a species of land crab that is endemic to Christmas Island and Cocos (Keeling) Islands in the Indian Ocean. Although restricted to a relatively small area, an estimated 43.7 million adu ...

'', which feeds on small seedlings. Vertebrates include geckos such as ''

Cyrtodactylus ''Cyrtodactylus'' (Greek κυρτος ''kurtos'' "curved", from κυπτω ''kuptō'' "to stoop"; δακτυλος ''daktulos'' "finger, toe") is a diverse genus of Asian geckos, commonly known as bent-toed geckos, bow-fingered geckos, and fores ...

'' and ''

Lepidodactylus listeri ''Lepidodactylus listeri'', also known commonly as Lister's gecko or the Christmas Island chained gecko, is a species of gecko, a lizard in the family Gekkonidae, endemic to Christmas Island in the Indian Ocean. It is currently extinct in t ...

'', and

skinks Skinks are lizards belonging to the family Scincidae, a family in the infraorder Scincomorpha. With more than 1,500 described species across 100 different taxonomic genera, the family Scincidae is one of the most diverse families of lizards. Sk ...

, specifically the ''

Cryptoblepharus egeriae ''Cryptoblepharus egeriae'', also known commonly as the blue-tailed shinning-skink, the Christmas Island blue-tailed shinning-skink, and the Christmas Island blue-tailed skink, is a species of lizard in the family Scincidae that was once endem ...

'' (Blue-tailed Skink), and '' Emoia nativitatis'' (Christmas Island forest skink); major invertebrates are also present, such as the

robber crab The coconut crab (''Birgus latro'') is a species of terrestrial hermit crab, also known as the robber crab or palm thief. It is the largest terrestrial arthropod in the world, with a weight of up to . It can grow to up to in width from the tip ...

, and the little nipper ''

Geograpsus grayi ''Geograpsus'' is a genus of crabs in the family Grapsidae The Grapsidae are a family of crabs known variously as marsh crabs, shore crabs, or talon crabs. The family has not been confirmed to form a monophyletic group and some taxa may belo ...

''. Murray Hill is an integral part of a reserve area which covers the entire southwest corner of the island. Initially, it was declared as the

declared by Proclamation under the National Parks and Wildlife Conservation Act 1975, on 21 February 1980, covering an area of 85 km² (out of total area of 135 km² of the island). On 16 July 2000, the Environment Protection and Biodiversity Conservation Act 1999 came into effect and the park is now a Commonwealth Reserve under this Act. As of 2010, the national park makes up 63 percent of Christmas Island.

References

External links

*
Murray Hill, Christmas Island
GeoNames. {{Highest points of Asia Geography of Christmas Island