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The major parts of the biosphere are connected by the flow of chemical elements and compounds in biogeochemical cycles. In many of these cycles, the biota plays an important role. Matter from the Earth's interior is released by volcanoes. The atmosphere exchanges some compounds and elements rapidly with the biota and oceans.
1: Extremely rare on the Earth's surface (less than 1×10 −7 %, i.e. less than 1/10 as common as the least common essential element, selenium), thus has low potential for any kind of biological role. a: Toxic in some molecular forms. b: Radioactive. c: Has uses in medicine as a drug or implant.
[4] Carbonaceous asteroids are rich in CHON elements. [5] These asteroids are the most common type and frequently collide with Earth as meteorites. Such collisions were especially common early in Earth's history, and these impactors may have been crucial in the formation of the planet's oceans. [6]
4 1: Animals: neuron function, electrolyte balance See also: Potassium in biology. Agriculture: fertilizers 20: Ca: Calcium 4 2: Animals: structure of bones and teeth See also: Calcium in biology. Construction: cements and mortars 21: Sc: Scandium 4 3 22: Ti: Titanium 4 4 23: V: Vanadium 4 5 24: Cr: Chromium 4 6 25: Mn: Manganese 4 7 26: Fe ...
The rarest elements in the crust are not the heaviest, but are rather the siderophile elements (iron-loving) in the Goldschmidt classification of elements. These have been depleted by being relocated deeper into the Earth's core; their abundance in meteoroids is higher.
The Goldschmidt classification, [1] [2] developed by Victor Goldschmidt (1888–1947), is a geochemical classification which groups the chemical elements within the Earth according to their preferred host phases into lithophile (rock-loving), siderophile (iron-loving), chalcophile (sulfide ore-loving or chalcogen-loving), and atmophile (gas-loving) or volatile (the element, or a compound in ...
Rammed earth is more often considered for use in walls, although it can also be used for floors. Rammed earth and caliche block can be used for structural walls, and offer great potential as low-cost material alternatives with low embodied energy. In addition, such materials are fireproof. Caliche block and rammed earth can be produced on-site.
32 of these have names tied to the Earth and the other 10 have names connected to bodies in the Solar System. The first tables below list the terrestrial locations (excluding the entire Earth itself, taken as a whole) and the last table lists astronomical objects which the chemical elements are named after. [1]