The McMurdo Volcanic Group is a large group of Cenozoic

volcanic rock Volcanic rock (often shortened to volcanics in scientific contexts) is a rock formed from lava erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin. Like all rock types, the concept of volcanic ...

s in the western

Ross Sea The Ross Sea is a deep bay of the Southern Ocean in Antarctica, between Victoria Land and Marie Byrd Land and within the Ross Embayment, and is the southernmost sea on Earth. It derives its name from the British explorer James Clark Ross who ...

and central

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

areas 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, it contains the geographic South Pole. Antarctica is the fifth-largest cont ...

. It is one of the largest

provinces A province is almost always an administrative division within a country or state. The term derives from the ancient Roman '' provincia'', which was the major territorial and administrative unit of the Roman Empire's territorial possessions ou ...

of alkaline

volcanism Volcanism, vulcanism or volcanicity is the phenomenon of eruption of molten rock (magma) onto the surface of the Earth or a solid-surface planet or moon, where lava, pyroclastics, and volcanic gases erupt through a break in the surface called a ...

in the world, having formed as a result of continental

rift In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-grabe ...

ing along the

West Antarctic Rift System The West Antarctic Rift System is a series of rift valleys between East and West Antarctica. It encompasses the Ross Embayment, the Ross Sea, the area under the Ross Ice Shelf and a part of Marie Byrd Land in West Antarctica, reaching to the ...

. The McMurdo Volcanic Group is part of the Western Ross Supergroup, a

stratigraphic unit A stratigraphic unit is a volume of rock of identifiable origin and relative age range that is defined by the distinctive and dominant, easily mapped and recognizable petrographic, lithologic or paleontologic features (facies) that characterize ...

that also includes the Meander Intrusive Group.

Subdivisions

Three subprovinces comprise the McMurdo Volcanic Group, namely the Hallett, Melbourne and Erebus volcanic provinces. The Balleny Volcanic Province along the Balleny Fracture Zone in the

Southern Ocean The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. With a size of , it is regarded as the second-small ...

was originally defined as part of the McMurdo Volcanic Group but is now excluded due to its location on

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 ultramafic ...

with no obvious geographic or tectonic relationship to the other McMurdo volcanic provinces.

Hallett Volcanic Province

The Hallett Volcanic Province in northern

Victoria Land Victoria Land is a region in eastern Antarctica which fronts the western side of the Ross Sea and the Ross Ice Shelf, extending southward from about 70°30'S to 78°00'S, and westward from the Ross Sea to the edge of the Antarctic Plateau. I ...

is situated along the margin of the Transantarctic Mountains. It consists of a long chain of four major elongated shield volcano complexes that were originally interpreted to have erupted subglacially under a larger Antarctic ice sheet. Later studies showed that they erupted in a subaerial environment instead.

Volcanoes

Adare Peninsula The Adare Peninsula, sometimes called the Cape Adare Peninsula, is a high ice-covered peninsula, long, in the northeast part of Victoria Land, extending south from Cape Adare to Cape Roget. The peninsula is considered the southernmost point of ...

** Hanson Peak ** Hargreaves Peak *

Coulman Island Coulman Island is an ice-covered island in the Ross Sea, located southeast of Cape Jones, Victoria Land, Antarctica. It is long, wide and in elevation. Emperor penguins inhabit this island. It was discovered in 1841 by Sir James Clark Ros ...

Hawkes Heights Hawkes Heights (or Mount Hawkes) is an ice-filled volcanic crater rising to that dominates the southern part of Coulman Island, in the Ross Sea, Antarctica, and marks the island's summit. The feature was named by the New Zealand Geological Survey ...

* Daniell Peninsula ** Mount Brewster ** Mount Lubbock ** Mount Prior **

Tousled Peak Tousled Peak () is a small ice-covered peak, 1,220 m, situated 3.5 nautical miles (6 km) northwest of the summit of Mount Lubbock in the south end of Daniell Peninsula, Victoria Land. The name given by New Zealand Antarctic Place-Na ...

* Hallett Peninsula ** Quarterdeck Ridge ** Redcastle Ridge ** Mount Vernon Harcourt

Melbourne Volcanic Province

The Melbourne Volcanic Province is also in northern Victoria Land and forms an arcuate band extending from the Ross Sea coast into the Transantarctic Mountains. It consists of large volcanic centres and small but widely distributed

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 ...

ic vents.

Volcanoes

* Mount Abbott * Baker Rocks * Malta Plateau * Markham Island *

Mount Melbourne Mount Melbourne is a ice-covered stratovolcano in Victoria Land, Antarctica, between Wood Bay and Terra Nova Bay. It is an elongated mountain with a summit caldera filled with ice with numerous parasitic vents; a volcanic field surrounds the e ...

* Nathan Hills * Mount Noice * Mount Overlord ** Parasite Cone * The Pleiades ** Alcyone Cone ** Mount Pleiones ** Taygete Cone * Random Hills *

Mount Rittmann Mount Rittmann is a volcano in Antarctica. Discovered in 1988–1989 by an Italian expedition, it was named after the volcanologist Alfred Rittmann (1893–1980). It features a or wide caldera which crops out from underneath the Aviator Glacie ...

* Shield Nunatak

Erebus Volcanic Province

The Erebus Volcanic Province is in southern Victoria Land. It includes marine volcanic centres in the southwest Ross Sea, major volcanic complexes in southern

McMurdo Sound McMurdo Sound is a sound in Antarctica. It is the southernmost navigable body of water in the world, and is about from the South Pole. Captain James Clark Ross discovered the sound in February 1841, and named it after Lt. Archibald McMurdo ...

and several small basaltic centres in the

McMurdo Dry Valleys The McMurdo Dry Valleys are a row of largely snow-free valleys in Antarctica, located within Victoria Land west of McMurdo Sound. The Dry Valleys experience extremely low humidity and surrounding mountains prevent the flow of ice from nearby ...

, as well as along the foothills of the

Royal Society Range The Royal Society Range () is a mountain range in Victoria Land, Antarctica. With its summit at , the massive Mount Lister forms the highest point in this range. Mount Lister is located along the western shore of McMurdo Sound between the Koett ...

Volcanoes

* Beaufort Island * Black Island ** Mount Aurora ** Mount Melania * Brandau Crater *

Brown Peninsula Brown Peninsula () is a nearly ice-free peninsula, long and wide, which rises above the Ross Ice Shelf northward of Mount Discovery, to which it is connected by a low isthmus. It was discovered by the British National Antarctic Expedition, 1901� ...

Mount Discovery Mount Discovery is a conspicuous, isolated stratovolcano, lying at the head of McMurdo Sound and east of Koettlitz Glacier, overlooking the NW portion of the Ross Ice Shelf. It forms the center of a three-armed mass of which Brown Peninsula is o ...

* Franklin Island *

Mount Morning Mount Morning is a shield volcano at the foot of the Transantarctic Mountains in Victoria Land, Antarctica. It lies from Ross Island. Mount Morning rises to an elevation of and is almost entirely mantled with snow and ice. A wide summit calder ...

* Ross Island **

Mount Bird Mount Bird is a high shield volcano standing about south of Cape Bird, the northern extremity of Ross Island. It was mapped by the British National Antarctic Expedition, 1901–04, under Robert Falcon Scott, and apparently named by them aft ...

** Black Knob ** Boulder Cones ** Castle Rock **

Mount Erebus Mount Erebus () is the second-highest volcano in Antarctica (after Mount Sidley), the highest active volcano in Antarctica, and the southernmost active volcano on Earth. It is the sixth-highest ultra mountain on the continent. With a summ ...

** First Crater ** Half Moon Crater ** Observation Hill ** Second Crater ** Mount Terror ** Twin Crater * White Island

References

{{reflist, 30em Volcanoes of Victoria Land Cenozoic volcanoes Volcanic groups Rift volcanoes Geologic formations of Antarctica

Subdivisions

Hallett Volcanic Province

Volcanoes

Melbourne Volcanic Province

Volcanoes

Erebus Volcanic Province

Volcanoes

See also

References