The small lake from which Medicine Lake volcano derives its name lies within the central caldera.
Their central calderas are also quite large in proportion to their base diameters.
On Niuafo'ou it is most common on the central caldera.
It is a volcanic island, dominated by a 1.6 km wide central caldera (the Caldeira) located in the southeast.
As the dust cleared, it became obvious that the spots were the tops of enormous shield volcanoes with complex central calderas (collapse craters).
At last they overlooked the central caldera, pocked by smaller calderas where the surface had collapsed after the hot lava leaked out.
The name "Uranius Patera" now refers only to the volcano's central caldera.
The subsidence of the summit to form the central caldera and the extraordinarily energetic earthquakes accompanying the 1912 eruption are evidence of this.
The caldera complex consists of a central caldera surrounded by four coalesced calderas.
Crater counting indicates that the central caldera is about 100 million years (Myr) old.