Atmospheric deposition lithosphere

The solid crust and the upper mantle make up the region called the lithosphere. Oxygen is the most abundant element in the lithosphere. Unlike the hydrosphere and the atmosphere, the lithosphere contains a large variety of other elements, including deposits of alkali, alkahne earth, and transition metal elements. Table 26-3 lists the most abundant elements in the continental crust portion of the hthosphere. With the exception of gold, platinum, and a few other rare metals that are found free in nature, most metallic elements occur as compounds in minerals. A mineral is a solid, inorganic compound found in nature. Minerals have distinct crystalhne structures and chemical compositions. Most are combinations of metals and nonmetals. 

Carbon is released from the lithosphere by erosion and resides in the oceans ca. 10 years before being deposited again in some form of oceanic sediment. It remains in the lithosphere on the average 10 years before again being released by erosion (Broecker, 1973). The amount of carbon in the ocean-atmosphere-biosphere system is maintained in a steady state by geologic processes the role of biological processes is, however, of profound importance... 

The combustion of white phosphorus felt or red phosphorus butyl rubber will produce smoke. Smoke is an aerosol comprised of oxides of phosphorus (phosphorus pentoxide and phosphorus trioxide), some of their transformation products (see Section 3.2), and a small amount of unburnt phosphorus. The aerosol components in the smoke will undergo dispersion and chemical transformation in air to form acids or phosphorus, and will ultimately deposit from air to the hydrosphere and the lithosphere. The main components of the aerosol deposited over water and soil are acids of phosphorus. Under oxidizing conditions in soil and water, phosphorus acids will be transformed to phosphate or polyphosphates. Under reducing conditions, the disproportionation reaction of phosphorus acid can produce phosphine, and the gas may be released to the atmosphere. The fate of deposited unbumt phosphorus in water and soil has already been discussed in the preceding paragraph. 

This chapter focuses on the interactions of radionuclides with geomedia in near-surface low-temperature environments. Due to the limitations on the chapter length, this review will not describe the mineralogy or economic geology of uranium deposits the use of radionuclides as environmental tracers in studies of the atmosphere, hydrosphere, or lithosphere, the nature of the nuclear fuel cycle or processes involved in nuclear weapons production. Likewise, radioactive contamination associated with the use of atomic weapons during World War 11, the contamination of the atmosphere, hydrosphere, or lithosphere related to nuclear weapons testing, and concerns... 

The combined active biomass of all primary producers acts as a gigantic pump that concentrates inorganic carbon dispersed in both the atmosphere and hydrosphere and deposits it in the reduced organic form, (CH20) . A comparison between the average contents (%w/w) of carbon in the atmosphere (0.03), hydrosphere (0.0014) and lithosphere (0.16), as opposed to that of the biosphere (24.9), impressively illustrates the efficiency of the biological carbon pump (see Deevey, 1970). 

The element has three valence states and is found in the environment in the metallic form and in the form of various inorganic and organic complexes. The major features of the bio-geochemical cycle of mercury include degassing of mineral mercury from the lithosphere and hydrosphere, long-range transport in the atmosphere, wet and dry deposition to land and surface water, sorption to soil and sediment particulates, revolatilization from land and surface water, and bioaccumulation in both terrestrial and aquatic food chains. 

In this chapter we consider the development and evolution of modem biosphere during its geological history. The reader will find a brief description of the formation of the lithosphere, atmosphere, and hydrosphere and their chemical composition. Creation and evolution of the biogeochemical structure of the biosphere and hydrosphere is also a subject of discussion. Finally, we show the role of biogeochemical cycles in formation of biogenic depositions (oil and gas). 

Carbon is the twelfth most abundant element in the Earths crust, although it accounts for only c.0.08% of the combined lithosphere (see Box 1.2), hydrosphere and atmosphere. Carbon-rich deposits are of great importance to humans, and comprise diamond and graphite (the native forms of carbon), calcium and magnesium carbonates (calcite, limestone, dolomite, marble and chalk) and fossil fuels (gas, oil and coal). Most of these deposits are formed in sedimentary environments, although the native forms of C require high temperature and pressure, associated with deep burial and metamorphism. 

The long time intervals that separate the deposition of marine carbonates and the return of volcanic CO2, i.e. the above reaction in reverse, as a result of the thermal decomposition of carbonates deep within the lithosphere, can lead to an imbalance in atmospheric CO2 concentrations. 

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