Big Ben is a volcanic

Volcano

2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

 massif

Massif

In geology, a massif is a section of a planet's crust that is demarcated by faults or flexures. In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole...

 that dominates the geography of Heard Island

Heard Island and McDonald Islands

The Heard Island and McDonald Islands are an Australian external territory and volcanic group of barren Antarctic islands, about two-thirds of the way from Madagascar to Antarctica. The group's overall size is in area and it has of coastline...

 in the southern Indian Ocean

Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...

. It is a composite cone with a diameter of approximately 25 kilometres. Its highest peak is Mawson Peak

Mawson Peak

Mawson Peak is a mountain on Heard Island, an external Australian territory in the Southern Ocean. With its summit at , it is the second highest peak in any state or territory of Australia, surpassed only by the Mount McClintock in the Britannia Range in Australian Antarctic Territory...

, which is 2,745 m above sea level

Above mean sea level

The term above mean sea level refers to the elevation or altitude of any object, relative to the average sea level datum. AMSL is used extensively in radio by engineers to determine the coverage area a station will be able to reach...

. Much of it is covered by ice, including 14 major glacier

Glacier

A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...

s which descend from Big Ben to the sea. Big Ben is the highest mountain in Australian Territory. A smaller volcanic headland, the Laurens Peninsula

Laurens Peninsula

Laurens Peninsula is a rugged peninsula surmounted by several ice-covered peaks. It forms the northwestern part of Heard Island in the southern Indian Ocean. The name was applied by the ANARE following their survey in 1948...

, extends approximately 10 km to the northwest, created by a separate volcano, Mount Dixon; its highest point is Anzac Peak

Anzac Peak

Anzac Peak is a 715 m  high volcano on the Laurens Peninsula of Heard Island in the Southern Ocean. It lies to the northwest of Mawson Peak...

, at 715 m.

External links

• Click here to see a map of Heard Island and McDonald Islands, including all major topographical features
• Location and history of Heard Island