GROUND WATER IN NORTH-CENTRAL TENNESSEE

220 GROUND WATER IN NORTH-CENTRAL TENNESSEE
WILSON COUNTY
[Area, 613 square miles. Population, 23,929]
GENERAL FEATCJRES
Wilson County, which occupies the east-central part of the region
covered by this report (pi. 1), is bounded on the north by Sumner
County, on the south by Rutherford County, and on the west by
Davidson County. Its principal cities are the county seat, Lebanon
(population 4,656), and Watertown (population 928), both of which
are on the main line of the Tennessee Central Railroad.
This county, which lies near the center of the northern lobe of the
Nashville Basin, lies for the most part on a dissected plain, the Nash­
ville Basin peneplain (pp. 20-22), whose interstream flats slope gently
northwestward and generally are between 625 and 700 feet above sea
level. Its drains, which are adjusted to the present stage of the
Cumberland River, about 400 feet above sea level, radiate from the
southeastern quadrant of the county to the Cumberland River on
the north, the Stone River on the southwest, and Caney Fork of the
Cumberland River on the east. Near these major streams the sur­
face has been so deeply dissected by the closely spaced branches of
the dendritic tributaries that it bears little semblance to the original
peneplain. Away from the major streams, however, and especially
along the divide between the Cumberland and Stone Rivers, the
peneplain extends undissected for many miles. Not all of this dis­
trict is drained by the surface streams, for there are many small sink­
holes and some closed depressions covering 1 square mile or more
that drain radially inward and discharge into solution channels in the
limestone. The origin of some of these features is related to that of
the Nashville Basin peneplain, that of others to the older of the two
partial erosion cycles by which the peneplain was dissected. In con­
trast to this extensive dissected plain, the southeastern quadrant of
the county is a hilly and moderately rugged area of which only the
floors of the major valleys are correlative with the surrounding pene­
plain. Its hills and ridges, the highest of which are in the vicinity of
Green vale and reach 1,300 feet above sea level, are maturely eroded
outliers of the Highland Rim plateau (pp. 16-18), which covers exten­
sive areas in the adjoining counties.
Inasmuch as Wilson County lies on the axis and northwest flank of
the Nashville dome (pp. 62-63), its rock strata dip radially northward
and westward from its southeast corner, although this regional dip is
modified somewhat by open secondary folds. The rocks that crop
out embrace the lowest part of the Fort Payne formation and the
underlying Chattanooga shale, the latter of Upper Devonian or early
Mississippian age, as well as a nearly complete sequence of Ordovi-
cian formations down to the Ridley limestone (pp. 35-55). The