interpretation
caldera (Calderas) refers to the crater formed by a volcanic eruption, due to late natural or artificial damage becomes incomplete crater. These structures are still relatively complete crater, volcanic debris brick red indicating its position near volcanic pipes, from the pipes into the distance volcanic pyroclastic thinning sequentially, shows a large number of volcanic cinder block shape can also be seen, volcanic bombs of different sizes. Steel gray volcanic slag layer near to the distribution scale quite spectacular.
Main Categories
is formed by cause, caldera divided into three categories:
caldera eruption of formula (Explosion calderas) solely caused by eruption caldera mouth.
decanter caldera caldera (Subsidence calderas) formed solely by settling.
compound caldera (Composite calderas) after the eruption of the caldera settling generated.
NOTE: throughout caldera atlas source
Reason
caldera large area diameter is typically up to several miles or even hundreds of miles; more than ever we believe that the causes of the caldera is due to violent volcanic eruption (super volcano) are formed, but new research shows that the fall is the main reason.
Howel Williams cup-shaped portion that is purely volcano crater is formed, known as caldera eruption, but such a little crater mortar and the area is small.
regardless of the shape of the volcano is why the initial causes of all starting from the eruption, but a large amount after the eruption leads volcanic cone below empty, the volcano apex collapse such eruption population expansion, thereby making crater the range is more amplified, and therefore many of the caldera are the first result of eruption and then formed by a dual role led to the fall, and therefore some scholars believe that this statement should be called "fall said the outbreak" (Explosion-collapse theory) ; while a few caldera may be made solely due to sedimentation, settling occurs before and after this eruption was not accompanied by action, such as Mauna Loa crater on the Hawaiian Islands and Ji Laoya crater is simply because the magma column leads downwardly lower than the drop formation caused by the fall, and therefore around the crater often found fault cliff, and gradually shifted so that the cliff layer surrounding the crater and the expansion of the fall, followed by the formation of a large caldera; and among settling caldera have a more particular form, referred to as a pot-shaped settling (Cauldron subsidence), if there is a nearly circular hole which magma rock fall into the magma below the top by a circular pressure jumped around the vertical fracture, then cooled causing the annular dike, so cup-shaped crater is usually accompanied by an annular dike been configured erosion.
known crater
Aso volcano in northern Kyushu, Japan, Kumamoto Prefecture, slightly elliptical, north to south 24 km west width of 18 kilometers, an area of 250 sq. km. There are more than 10 crater (it is also called stratovolcano), and the formation of the Central Disaster Prevention Council in the fire Yamaguchi group, of which the high mountain, root Yue, Wu Yue hat, Zhongyue and pestle island's most famous mountain, known as Aso Five Sacred Mountains. Takaoka highest elevation of 1592 meters.