Mount Harcourt is a stratovolcano making up part of the Hallett Peninsula

Cape Hallett

Cape Hallett is a snow-free area on the northern tip of the Hallett Peninsula on the Ross Sea coast of Victoria Land, East Antarctica. A very large Adelie penguin rookery is located at Cape Hallett...

 extending into the Ross Sea

Ross Sea

The Ross Sea is a deep bay of the Southern Ocean in Antarctica between Victoria Land and Marie Byrd Land.-Description:The Ross Sea was discovered by James Ross in 1841. In the west of the Ross Sea is Ross Island with the Mt. Erebus volcano, in the east Roosevelt Island. The southern part is covered...

 about 375 mi (604 km) south of Mount Erebus

Mount Erebus

Mount Erebus in Antarctica is the southernmost historically active volcano on Earth, the second highest volcano in Antarctica , and the 6th highest ultra mountain on an island. With a summit elevation of , it is located on Ross Island, which is also home to three inactive volcanoes, notably Mount...

, along with three overlapping shield volcano

Shield volcano

A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their large size and low profile, resembling a warrior's shield. This is caused by the highly fluid lava they erupt, which travels farther than lava erupted from more explosive volcanoes...

es. Two dates have been obtained from the volcano's rock, roughly 5.5 and 6.6 million years in age. These samples are alkalic in composition. The volcano is known to be a site of Boscoia sudpolaris

Hypogastruridae

Hypogastruridae is a family of springtails. Members of the family are common and widespread with a cosmopolitan distribution of about 660 species in about 40 genera.-Selected genera:Hypogasturidae genera are:* Acherongia Massoud & Thibaud, 1985...

.