Atmosphere juvenile

The sedimentary and metamorphic rocks uplifted onto land have become part of continents or oceanic islands. These rocks are now subject to chemical weathering. The dissolved and particulate weathering products are transported back to the ocean by river runoff. Once in the ocean, the weathering products are available for removal back into a marine sedimentary reservoir. At present, most mass flows on this planet involve transport of the secondary (recycled) materials rather than the chemical reworking of the primary (juvenile) minerals and gases. The natirre of these transport and sediment formation processes has been covered in Chapters 14 through 19 from the perspective of the secondary minerals formed. We now reconsider these processes from the perspective of impacts on elemental segregation between the reservoirs of the crustal-ocean-atmosphere factory and the mantle. 

Juvenile It is generally believed that the Earth s atmosphere was formed by degassing of volatiles from the interior. Volatiles that have remained in the Earth s interior, have never been part of the atmosphere, and are observed to be entering the atmosphere for the first time are designated as juvenile. Atmospheric is an antonym to juvenile. 

Inputs and outputs of calcium, magnesium, and carbon can be balanced for the modern ocean. This balance necessitates reverse weathering reactions in the ocean system in which CO2 consumed in weathering on land is released to the ocean-atmosphere system during the formation of minerals in the ocean. If this were not the case, regardless of juvenile emissions of CO2 to the ocean-atmosphere system, atmospheric CO2 concentrations could be reduced to vanishingly small values in less than 5000 years. 

Conyers, S.T. and Bell, C.H. (1997) The effect of modified atmospheres on the juvenile stages of six grain beetles. Proceedings of the International Conference on Controlled Atmosphere and Fumigation in Stored Products, Nicosia, Cyprus, April 1996, Dona-haye, E.J., Navarro, S. and Vamava, A., pp. 73-81. 

According to their origin, waters are classified into juvenile waters (formed in the primary differentiation of the substances of the earth s envelope) and recirculated waters (participating in the hydrologic cycle in the atmosphere). The continuous circulation of water is induced by solar energy and earth s gravity. 

Figure 17.1 The nitrogen cycle. Although the supply of nitrogen In the atmosphere is virtually inexhaustible, it must be combined with hydrogen or oxygen before it can be assimilated by higher plants, which in turn are consumed by animals. Juvenile nitrogen is nitrogen that has not previously participated in the nitrogen cycle.

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