GROUND WATER IN NORTH-CENTRAL TENNESSEE
GROUND WATER IN NORTH-CENTRAL TENNESSEE
GROUND WATER IN NORTH-CENTRAL TENNESSEE
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STEWABT COUNTY 191<br />
_ In addition to recent alluvial deposits along the major streams,<br />
Stewart County embraces both unconsolidated and consolidated rocks,<br />
which range in age from Upper Cretaceous to Lower Ordovician,<br />
although the full stratigraphic sequence of the Nashville Basin is not<br />
recognized. The unconsolidated deposits include the fine mica<br />
ceous sands of the Eutaw formation and the underlying chert gravel<br />
of the Tuscaloosa formation, which cover an extensive tract on the<br />
divide between the Tennessee and Cumberland Rivers in the north<br />
west corner of the county. (See pi. 4.) The Tuscaloosa formation<br />
also occurs in a small area on the crest of the ridge west of Bear<br />
Spring. The youngest of the consolidated rocks are the massive and<br />
medium-bedded St. Louis limestone and Warsaw formation, which<br />
constitute the bedrock over the greater part of the county. Visible<br />
exposures of these beds are uncommon, however, except in the youth<br />
ful stream trenches, for on all the remnants of the Highland Rim<br />
peneplain the bedrock is covered by 50 to 75 feet of residual clayey<br />
debris. The underlying Fort Payne formation, which in this county<br />
is a dense thin-bedded and extremely cherty limestone, crops out<br />
over the lower valley slopes of the Tennessee River and its tributaries<br />
in the western part of the county, also in the lower part of the Wells<br />
Creek Basin, near the southeast corner of the county. The carbo<br />
naceous Chattanooga shale underlies the Fort Payne formation and<br />
crops out just above stream level in the Tennessee River Valley at<br />
the mouth of Standing Rock Creek and farther north. It also crops<br />
out as a peripheral band surrounding the Wells Creek uplift and<br />
elsewhere in the Wells Creek Basin. The uppermost of the pre-<br />
Chattanooga rocks, which crop out only in the Wells Creek Basin,<br />
include the Linden formation, of Lower Devonian age, and a rather<br />
full sequence of Silurian limestones. These are in turn underlain by<br />
the Hermitage formation and the Lowville limestone, both of lower<br />
Middle Ordovician age, all Upper Ordovician strata and the upper<br />
part of the Middle Ordovician being absent. The Lowville is under<br />
lain directly by limestone of earliest Ordovician (Beekmantown?)<br />
age, which is the oldest rock cropping out in north-central Tennessee.<br />
The general character and stratigraphic relations of both the uncon<br />
solidated and consolidated rocks are discussed on pages 24-58, and their<br />
area! distribution is shown on Plate 4. However, the stratigraphic<br />
relations within the Wells Creek Basin are known only approximately.<br />
Stewart County lies on the flank of the Nashville dome, so that in<br />
general the strata constitute a monocline dipping very slightly north<br />
westward. In the extreme southeast corner of the county, however,<br />
this regional structure is modified by the Wells Creek uplift (pp. 65-67),<br />
within which the strata are steeply upturned, locally folded, and<br />
complexly faulted.