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A material invented by Dr. Brazzelton, who dubs it "unobtanium" as its technical name has 37 syllables. Unobtanium is able to convert heat and pressure into energy that reinforces its own structure, allowing the construction of a vessel capable of enduring a trip to the Earth's core. In addition, it can also turn heat into electric power.
A coal ball is a type of concretion, varying in shape from an imperfect sphere to a flat-lying, irregular slab.Coal balls were formed in Carboniferous Period swamps and mires, when peat was prevented from being turned into coal by the high amount of calcite surrounding the peat; the calcite caused it to be turned into stone instead.
Coal forms when organic matter builds up in waterlogged, anoxic swamps, known as peat mires, and is then buried, compressing the peat into coal. The majority of Earth's coal deposits were formed during the late Carboniferous and early Permian. The plants from which they formed contributed to changes in the Carboniferous Earth's atmosphere. [25]
Peat "hags" are a form of erosion that occur at the sides of gullies that cut into the peat; they sometimes also occur in isolation. [80] Hags may result when flowing water cuts downwards into the peat and when fire or overgrazing exposes the peat surface. Once the peat is exposed in these ways, it is prone to further erosion by wind, water and ...
A coal ball. Carbonate mineralization involves the formation of coal balls. Coal balls are the fossilizations of many different plants and their tissues. They often occur in the presence of seawater or acidic peat. Coal balls are calcareous permineralizations of peat by calcium and magnesium carbonates. Often spherical in shape and ranging from ...
Lignite (derived from Latin lignum meaning 'wood'), often referred to as brown coal, [1] is a soft, brown, combustible sedimentary rock formed from naturally compressed peat. It has a carbon content around 25–35% [ 1 ] [ 2 ] and is considered the lowest rank of coal due to its relatively low heat content .
Coal forest of tree ferns and lycopod trees, in a 1906 artist's rendering. The coal forests seem to have been areas of flat, low-lying swampy areas with rivers flowing through from higher, drier land. [4] When the rivers flooded, silt gradually built up into natural levees. Lakes formed as some areas subsided, while formerly wet areas became ...
"The Green Hills of Earth" is a science fiction short story by American writer Robert A. Heinlein.One of his Future History stories, the short story originally appeared in The Saturday Evening Post (February 8, 1947), and it was collected in The Green Hills of Earth (and subsequently in The Past Through Tomorrow).