Analysis of the Earths Crust - a Geochemical Task

The earth s crust is a thin shell with only 0.5% of the total mass of the earth. It has, however, a vital role in our existence, as the elements we use come mainly from this thin shell. 

The distribution of elements between the different parts - core, mantle, crust, hydrosphere and atmosphere - occurred mainly when the planetary system was formed, but a continuous redistribution occurs through different chemical and geological processes. 

In the investigation of the chemical composition of the earth the crust was naturally the target goal. During the 19 century, geochemical base data were received from mineral and rock analyses made in coimection with ore prospecting. 

Eariy Results from the US Ceolc ical Survey 

Component The Vernadsky Institute Mean values of many thousands of analyses Clarke and Washington Mean values of 5159 analyses Goldschmidt Mean values of 77 analyses  

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