Comparison between Laboratory and Field Weathering Results

10 Comparison between Laboratory and Field Weathering Results 

So far we have discussed weathering rates and rate laws from laboratory experiments on pure minerals. These laboratory studies are meant to provide insight for natural systems (rates and variables that affect these rates). We may first try to compare laboratory and field results. 

Chemical weathering introduces solutes into the natural waters draining (exported) from the catchment area. The rate of chemical weathering [mol per m2 catchment area per year] - one also speaks of chemical erosion or chemical denudation - can be estimated from the concentrations of the solutes in the waters running off (rivers)  

Comparison of the chemical composition of rivers Calancasca (southern Switzerland) draining silicate rocks and Glatt (northern Switzerland) draining CaCC 3 (calcite) bearing terrain. Because of the high population density anthropogenic effects are superimposed on the geological effects. 

In Table 5.3 some laboratory dissolution rates are compared with field measurements on solute export in silicate terrain. 

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