Tweed Volcano

- 28.395753153.266719Koordinaten: 28 ° 23 ' 45 "S, 153 ° 16' 0" E

The Tweed Volcano was a shield volcano from the early Miocene. It is located in north-eastern New South Wales in Australia and was created 23 million years ago. He is one of the largest volcanoes in the world and the largest eroded volcano in the southern hemisphere.

Over a period of three million years of the Tweed Volcano was fed by the East Australia hotspot, as this was below the Australian continent. For about 20 million years ago there were no eruptions or pyroclastic flows more because the hotspot migrated because of the continental drift outside the Australian continent.

The outbreaks of the Tweed Volcano formed of numerous layers of lava and volcanic ash and spread over an area of ​​Byron Bay in the southeast, in the southwest of Lismore in New South Wales and up to Mount Tamborine in the north of Queensland. Mount Warning, Lamington Plateau and the Border Ranges between New South Wales and Queensland are the most important visible relics of this volcano, which originally covered an area with a diameter of 100 km. The volcano had previously to a height of about 2000 meters, while today's highly visible Mount Warning rises 1156 m above the terrain. Despite its size, the Tweed Volcano was not a super volcano.

In the 20 million years after the end of the eruption, a strong erosion took place, which uncovered the remains of the caldera to the volcanic plug of Mount Warning and numerous rivers such as the Rous River and Oxley formed, which open into the Tweed River. The caldera of the volcano descends from above 1000 m and has a diameter of 40 km.

The lava of the Tweed Volcano was stratigraphically determined as part of the Lamington Volcanics. The volcanic stratigraphy of this volcano is similar to many other hotspot volcanoes on Earth, brought forth the eruptions of tholeiitic and other alkaline basalts.