Ionic ratio

Range

Comment

Interpretation

SO₄/Cl

0.00 - 0.36

High

Additional sources of SO₄ from weathering of sulfates

Na/Cl

0.01 - 1.32

High

Na-adsorption during freshening and a little silicate weathering

Mg/Cl

0 - 1.29

High

Cation-exchange and silicate weathering of sandstones.

Na/HCO₃

0.02 - 3.38

High

Substantial weathering of Na-feldspar or other Na-silicates

Ca/HCO₃

0.00 - 11.1

High

Calc-carbonate dissolution or Calc-silicate weathering

Ca/SO₄

0.00 - 75.2

High

Gypsum dissolution present

Ca/Mg

0.00 - 144.67

High

Cation-exchange of weathering of silicate rocks.

Ca + Mg/Na + K

0.00 - 10.25

High

Carbonate weathering

HCO₃/∑Anions

0.04 - 0.91

High

Weathering reactions and input of dissolved species in recharge area

NO₃/∑Anions

0.00 - 0.39

High

Anthropogenic contribution

SO₄/∑Anions

0.00 - 0.09

Low

No oxidation of sulphides.

Mg/Ca

0.00 - 2.44

Low

Weathering of Silicate rocks

Na/Na + Cl

0.01 - 0.57

High

Sodium source other than halite-albite, ion exchange

Mg/Ca + Mg

0.00 - 0.71

High

Dolomite dissolution, calcite precipitation or saltwater

Ca/Ca + SO₄

0.00 - 1.00

High

Calcium source other than gypsum

Ca + Mg/SO₄

0.00 - 195.26

High

Na + K − Cl/Na + K ? Cl + Ca

−4.39 - 112.22

High

Plagioclase weathering unlikely

Cl/∑Anions

0.08 - 0.93

High

Seawater or brine or evaporates