Fossil Cave (5L81), formerly known as The Green Waterhole, is a

cave A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

in the

Limestone Coast The Limestone Coast is a name used since the early twenty-first century for a South Australian government region located in the south east of South Australia which immediately adjoins the continental coastline and the Victorian border. The ...

region of south-eastern

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

. It is located in the gazetted locality of

Tantanoola Tantanoola is a town in regional South Australia. The name is derived from the aboriginal word ''tentunola'', which means ''boxwood / brushwood hill or camp''. ''Tantanoola'' was originally named 'Lucieton' by William Jervois, Governor Jervois a ...

about north-west of the city of

Mount Gambier Mount Gambier is the second most populated city in South Australia, with an estimated urban population of 33,233 . The city is located on the slopes of Mount Gambier, a volcano in the south east of the state, about south-east of the capital Ad ...

, only a few metres from the

Princes Highway Princes Highway is a major road in Australia, extending from Sydney via Melbourne to Adelaide through the states of New South Wales, Victoria and South Australia. It has a length of (along Highway 1) or via the former alignments of the hig ...

(Route B1) between Mount Gambier and

Millicent Millicent or Milicent is a female given name that has been in use since the Middle Ages. The English form Millicent derives from the Old French ''Melisende (disambiguation), Melisende'', from the Germanic ''amal'' "work" and ''swinth'' "strength". ...

. It is popular with cave divers and is notable for being both a unique

paleontological site A paleontological or fossiliferous site is a locality in which a significant quantity of fossils is naturally preserved in the rocks. The extent of the site is determined, in some cases, by the spatial distribution of the concentration of fossils ...

and the "type locality" for very rare crustaceans (syncarids - Koonunga sp.) which to date have been found only in caves and Blue Lake in the Mount Gambier region.

Description and naming

The cave is formed in 30-million-year-old Oligocene

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 secre ...

line

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms wh ...

. The cave is a karst

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...

and is largely filled with water. The surface depression is about long and wide. Beneath the surface it extends to a maximum length of and a width of . The name of the cave was changed on 23 April 1989 by the

Government of South Australia The Government of South Australia, also referred to as the South Australian Government, SA Government or more formally, His Majesty’s Government, is the Australian state democratic administrative authority of South Australia. It is modelled o ...

from ''The Green Waterhole'' to ''Fossil Cave'' with the change being published in

The South Australian Government Gazette ''The South Australian Government Gazette'' is the government gazette of the South Australian Government. The ''South Australian Gazette'' was first printed on 20 June 1839, after the South Australian Government chose to have its own publica ...

on 4 May 1989.

Fossils

Since the mid 1960s, a variety of

Pleistocene The Pleistocene ( , often referred to as the '' Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed ...

subfossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

material of birds and mammals has been found and recovered by divers from the surface of a rockpile to a depth of about below the water surface. The probable accumulation mode was by animals drowning when they fell into the cave while attempting to use it as a source of drinking water. Dating of the subfossil remains indicated that their deposition occurred mainly between 15,000 and 40,000 years ago. As well as representing many living animals, examples of extinct species recovered from the cave include the birds ''

Centropus colossus '' Centropus colossus '' is an extinct species of coucal from the Late Pleistocene of Australia. It was described from submerged subfossil material (a slightly damaged left humerus) collected in 1979 from the Fossil Cave in the south-east of So ...

'' and ''

Orthonyx hypsilophus '' Orthonyx hypsilophus '' is an extinct species of logrunner from the Late Pleistocene of Australia. It was described from submerged subfossil material (an incomplete pelvis) collected in 1979 from the Fossil Cave in the south-east of South ...

'', and the mammals '' Thylacinus cynocephalus'', '' Thylacoleo carnifex'', '' Propleopus oscillans'', ''

Macropus titan ''Macropus titan'' is an extinct species of kangaroo (a marsupial) that lived during the Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11, ...

'', '' Protemnodon anak'', and the sthenurine kangaroos ''

Procoptodon gilli ''Procoptodon'' is an extinct genus of giant short-faced (sthenurine) kangaroos that lived in Australia during the Pleistocene Epoch. ''P. goliah'', the largest known kangaroo species that ever existed, stood at about . They weighed about . Other ...

'', ''

Procoptodon maddocki ''Procoptodon'' is an extinct genus of giant short-faced (sthenurine) kangaroos that lived in Australia during the Pleistocene Epoch. ''P. goliah'', the largest known kangaroo species that ever existed, stood at about . They weighed about . Other ...

'' and '' Simosthenurus occidentalis''.

Exploration

Fossils were first collected from the cave in 1964 followed by a further collection in 1968 and logged with the

South Australian Museum The South Australian Museum is a natural history museum and research institution in Adelaide, South Australia, founded in 1856 and owned by the Government of South Australia. It occupies a complex of buildings on North Terrace in the cu ...

. During the next two decades a number of more extensive surveying, sedimentology and bone-recovery operations were carried out by cave divers working in conjunction with palaeontologist Dr Rod Wells and researcher Cate Newton (Flinders University) and the South Australian Underwater Speleological Society (SAUSS) Inc. The cave's submerged extent has been surveyed at least three times including by the Flinders University Underwater Club (FUUC) in 1978, Allum and Garrad in 1979 and SAUSS in 1987.

Recreational diving

Fossil Cave is a notable cave diving site. Access for cave diving is limited to holders of the Cave Divers Association of Australia's Advanced Cave grade.

References

External links