The Ross orogeny was a

mountain building Mountain formation occurs due to a variety of geological processes associated with large-scale movements of the Earth's crust (List of tectonic plates, tectonic plates). Fold (geology), Folding, Fault (geology), faulting, Volcano, volcanic acti ...

event in

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. ...

in the early

Paleozoic The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma a ...

. The ancestral (also termed proto-) Trans-Antarctic Mountains were uplifted earlier by the Beardmore orogeny but had eroded as a broad epicratonic sea flooded much of Antarctica in the

Cambrian The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordov ...

. Shallow water sedimentary rocks, platform carbonates and deepwater turbidites from this period are found in the mountain range. The Ross orogeny was one of the most extensive orogenic events in Antarctica, causing widespread plutonism and metamorphism. Bimodal magmatism and extension mark the beginnings of the orogeny, while during the later phase sedimentary rocks at the

continental margin A continental margin is the outer edge of continental crust abutting oceanic crust under coastal waters. It is one of the three major zones of the ocean floor, the other two being deep-ocean basins and mid-ocean ridges. The continental marg ...

were deformed, metamorphosed and intruded with

granite Granite ( ) is a coarse-grained (phanerite, phaneritic) intrusive rock, intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly coo ...

batholiths A batholith () is a large mass of intrusive igneous rock (also called plutonic rock), larger than in area, that forms from cooled magma deep in the Earth's crust. Batholiths are almost always made mostly of felsic or intermediate rock types, s ...

. Interpretations of rock forms in Antarctica during the 1980s suggested a westward-dipping subduction zone may have formed along the paleo-Pacific Ocean shoreline of

East Antarctica East Antarctica, also called Greater Antarctica, constitutes the majority (two-thirds) of the Antarctic continent, lying primarily in the Eastern Hemisphere south of the Indian Ocean, and separated from West Antarctica by the Transantarctic ...

. This is inferred from a large number of I-type and S-type granitoids which are similar to large circum-Pacific batholiths. During the

Late Cambrian The Furongian is the fourth and final Epoch (geology), epoch and Series (stratigraphy), series of the Cambrian. It lasted from to million years ago. It succeeds the Miaolingian series of the Cambrian and precedes the Lower Ordovician Tremadocia ...

Early Ordovician The Early Ordovician is the first epoch (geology), epoch of the Ordovician period, corresponding to the Lower Ordovician series (stratigraphy), series of the Ordovician system. It began after the Cambrian Stage 10, Age 10 of the Furongian epoch o ...

, 450-520 Ma,

sediments Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...

within the

Transantarctic Mountains The Transantarctic Mountains (abbreviated TAM) comprise a mountain range of uplifted rock (primarily sedimentary) in Antarctica which extends, with some interruptions, across the continent from Cape Adare in northern Victoria Land to Coats L ...

were

uplifted ''Uplifted'' is the second studio album by Nigerian singer Flavour N'abania. It was released on July 20, 2010, by Obaino Music and 2nite Entertainment. The album features guest appearances from Jah Dey, Oloye, Stormrex, Waga Gee, Asem, Stone, M-Ja ...

, folded,

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 ...

, and

intruded 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: March 27 ...

by granitoid batholiths. Evidence of this origin may be found in the

Shackleton Range The Shackleton Range () is a mountain range in Antarctica that rises to and extends in an east–west direction for about between the Slessor and Recovery Glaciers. Surveys The Commonwealth Trans-Antarctic Expedition (CTAE), which in 1956 s ...

, the

Pensacola Mountains The Pensacola Mountains () are a large group of mountain ranges and peaks that extend in a northeast–southwest direction in the Transantarctic Mountains System, Queen Elizabeth Land region of Antarctica. They comprise the Argentina Range, Forre ...

Thiel Mountains The Thiel Mountains () are isolated, mainly snow-capped mountains of the Transantarctic Mountains System, located in the Ellsworth Land region of Antarctica. The mountain range is long, is located roughly between the Horlick Mountains and the Pe ...

Horlick Mountains The Horlick Mountains () are a mountain group in the Transantarctic Mountains of Antarctica, lying eastward of Reedy Glacier and including the Wisconsin Range, Long Hills and Ohio Range. Discovery and naming The mountains were discovered in ...

, and the

Queen Maud Mountains The Queen Maud Mountains () are a major group of mountains, ranges and subordinate features of the Transantarctic Mountains, lying between the Beardmore Glacier, Beardmore and Reedy Glaciers and including the area from the head of the Ross Ice Sh ...

References

Ross Ross may refer to: People and fictional characters * Ross (name), including a list of people and fictional characters with the surname or given name Ross, as well as the meaning * Clan Ross, a Highland Scottish clan Places Antarctica * Ross Sea ...

Paleozoic orogenies {{Orogeny-stub

See also

References