GROUND WATER IN NORTH-CENTRAL TENNESSEE

182 GROUND WATER IN NORTH-CENTRAL TENNESSEE
derived from the upper part of the Murfreesboro limestone, is rela­
tively concentrated in sodium, sulphate, and chloride and usually
contains hydrogen sulphide. Analyses 432 and 433 are representa­
tive. Analyses 427 and 435 represent more dilute waters, which are
427 432 433 435 439
FIGUEE 6. Chemical character of representative ground waters from the Murfreesboro limestone.
presumably a mixture of the calcium-magnesium bicarbonate and
sodium bicarbonate-sulphate waters. The chemical character of
these representative waters is also shown graphically by Figure 6.
The water from some wells and springs in this zone contains a rela­
tively large quantity of iron, which in the presence of air is precipi-
1100