Page 84 - Hydrogeology Principles and Practice

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Physical hydrogeology 67

BO X
Continued
2.11

Fig. 4 Map showing areas of recharge and natural spring discharge together with the directions of regional groundwater flow.
After Habermehl (1980).

and yield residence times from several thousands of years near the as sodium and bicarbonate ions. Water quality improves with increas-
marginal recharge areas to more than one million years near the ing depth of aquifers in the sequence and on the whole the ground-
centre of the Basin (for further discussion see Section 4.4.3 and water is suitable for domestic and stock use, although it is generally
Bentley et al. 1986; Love et al. 2000). unsuitable for irrigation use due to the high sodium concentration
Groundwater in the most widely exploited artesian aquifers and its chemical incompatibility with the montmorillonite clay soils.
in the Lower Cretaceous–Jurassic sequence generally contains be- Groundwater from aquifers in the upper part of the Cretaceous
−1
tween 500 and 1000 mg L of total dissolved solids, predominantly sequence has a higher salinity.