Isotopic Fractionation During Evaporation and Some Hydrological Applications

3 Isotopic Fractionation During Evaporation and Some Hydrological Applications 

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In surface water bodies that evaporate to a very great extent, the isotopic enrichment ceases or is even reversed. However, except in very rare cases, natural water bodies, such as lakes or rivers, are only partially evaporated in the range in which isotopic enrichment of the residual water occurs. 

Isotopic fractionation during evaporation causes fractionation during cloud formation the vapor in the clouds has a lighter isotopic composition than the ocean that supplied the water. Upon condensation from the cloud, during rainformation, the reverse is true the heavy water molecules condense more efficiently, leaving the cloud residual vapor depleted of deuterium and lsO. 

At Orapa, northern Botswana, a new well field of confined water was developed and two hypotheses were proposed to explain the origin of 

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