316 GEOLOGY OF OHIO. 
the bed of an old, shallow swamp, now five or six feet above the present 
channel of the adjacent stream. The stratum is from two to three feet 
in thickness, but not of sufficient extent to be of any great value. 
GEOLOGICAL STRUCTURE. 
The geological structure of Richland county is easily read, and has 
little variety. No single exposure discloses all the rocks of the series, 
and as the dip is often quite considerable, and is without uniformity, the 
measurements of the different strata are only approximations. 
The section here given is the result of many observations and meas- 
urements, and will illustrate the general character of the eeological 
structure. 
GENERAL SECTION OF THE ROCKS OF RICHLAND COUNTY. 
Slese 
S SY TO TR 
R= ==SSnd=o eS 
Carboniferous Conglomerate. 
Argillaceous and siliceous shales....... ele eae Leen nad aie RIN 170 to 250 feet. 
ae Waverly Conclomeratemneteeererre teeter Heep r ener elt 100 to 190 feet. 
eek 
ea 
ese: ° 
Argillaceous and sandy shales, sometimes bituminous..-.--.--..- 65 feet. 
zee 
= Shales, with bands of flaggy sandstone............-.-.---------- 235 feet. 
it 
| 
J tr 
; 1 i { : 
SUCH cease NT Uae Berea sandstone. 
The highest hills in the north-eastern parts of the county are capped 
with the Carboniferous Conglomerate, which is in general quite thin, 
rarely attaining a thickness of twenty feet. It frequently contains frag- 
