24 GEOLOGY AND MINERAL RESOURCES OF MISSISSIPPI. 
prairies of Pontotoc and Monroe, during the wet season, present more formidable obstacles to the wag- 
oner than do the bottoms ami-hillsides of the Flatwoods region. Hence the great frequency among its 
streams of such names as Mud Creek and others still more eloquently expressive of the awe in which they 
are held by those who are- habitually obliged to traverse the Flatwoods. 
There are ncrwells to the writer's knowledge, which have been dug through the Porters 
Creek, nor any rivers crossing at a right angle to the strike of the formation, by which to 
determine its thickness. Estimated from the width of outcrop, with a westward dip of 15 
feet to the mile and a maximum width of outcrop of 14 miles, the thickness, is 210 feet. The 
more probable thickness, as observed from surface outcrops in Tippah County, is about 
100 feet. 
On the road leading northwest from Ripley the gray Porters Creek clay is present to the 
top of the hill 1\ miles northwest of town, also 2\ miles north of town and at various 
places along the railroad between Ripley and Walnut. Its thickness, as measured on the 
hill northwest of Ripley, is 75 feet. 
One-half mile north of Walnut the gray, lead-colored clay, which at Ripley rests on the 
thin band of sandstone and is 34 feel above the top of the Turritclla rock, outcrops in the 
deep ravine south of the railroad water tank. The same clay outcrop continues along the 
track one-half mile north of the water tank. 
Wesi of Walnut the hills rise 100 feet or more above the lowlands along the streams. On 
some of the hillsides the surface soil has been removed by heavy rains, and a more complete 
section of the Lower Eocene strata is exposed. One mile west-southwest of Walnut the 
same gray, lead-colored clay as that in Ripley and at the water tank north of Walnut shows 
on the steep hillside just south of a little stream flowing eastward, to a height of 40 feet 
above the stream. 
About 3 miles south-southwest of Walnut, on the farm of John Wright, a hill 50 feet above 
the stream contains numerous ledges of gray sandstone. At the foot of the hill, in Mr. 
Wright's yard, the sand-tone is -oil , resembling the rotten claystone of the Tallahatta buhr- 
stone in Newton County, described on page 29. The ledges near the top of the hill are 
very hard and contain large casts of fossils. The fossils collected from this local- 
ity were referred to Dr. W. H. Dall and were said to be Eocene, but no closer determination 
was made. The rock is a very coarse-grained sandstone, containing more or less greensand 
and mica. This sandstone overlies the gray clay referred to above. 
The same sandstone occurs on the high hills northeast of Tiplersville, where it is also under- 
lain by gray clay.a 
From the above data the following section, which shows the relations of the Eocene of 
Tippah County overlying the Cretaceous, may be given: 
Generalized section of the Midway group in Tippah County. 
Feet. 
{6. Gray fossiliferous sandstone capping tops of hills northeast of Tiplersville and 
southwest of Walnut 50-75 
5. Gray, lead-colored, noncalcareous clay, weathering white as seen 1 mile north of 
Walnut and in the vicinity of Ripley 50-75 
14. Greenish to gray sandstone, as seen at Chalybeate and imthe town of Ripley \- 2 
3. Yellow micaceous sandy marl, in places fossiliferous, seen at Ripley and Chalybeate. 30-34 
2. Turritella limestone, seen at Chalybeate and east of Ripley 5-15 
Cretace- 1. " Owl Creek " marl, of Cretaceous age. 
ous: 
The same order of Midway strata that is found in Tippah County continues southward 
through Union and Pontotoc counties, but the exposures are less frequent. Three miles 
west of Ecru, on the farm of Clay Lemon, is a gray sandstone similar in appearance 
to that in Tippah County. The hard ledge of limestone outcropping on the west bank of the 
branch along the Ecru and Oxford road one -half mile west of Ecru is doubtless the limestone 
of Clayton age, though no fossils were obtained from this locality. 
One and three-fourths miles south of the town of Pontotoc, in a deep cut on the line of the 
new railroad, is a greenish-yellow coarse-grained sand from which a lew fossils were collected 
oSee Geology and Agriculture of Mississippi, 1860, p. 112. 
