THE MID DEE COAL MEASORES: 585 
at one point an unconformable conglomerate.’ Little is known 
of this formation, but it seems to be essentially local. The beds 
between the upper member of the Appanoose, the ‘floating 
rock” of the miners and the lowermost member of the Bethany 
as shown in Decatur county are but infrequently exposed and 
little is known concerning them. If one may judge from the 
topography and the infrequent exposures, the intervening beds 
are shales, predominantly sandy. 
The three Iowa sections from the St. Louis limestone to 
the Bethany may be summarized as below: 
NORTHERN SECTION: MIpDLE SECTION: SOUTHERN SECTION: 
Jasper, Polk, Dallas, and Guth- Monroe, Lucas, and Clark Van Buren, Davis, Appanoose, 
rie counties counties Wayne, and Decatur counties 
Feet Feet Feet 
3. Sandy shales 3. Beds cover- 3. Sandy shales, 
not to be sep- ed; probably only partially 
arated from sandy shales, 50-70 exposed, 75 
the underly- (Chariton 
ingformation, 30 Conglom- 
erate, local.) 
. Appanoose 
N 
N 
. Shales, lime- 
N 
. Equivalents, 
stone, three section not beds) - 100 
coal beds, up- yet made out, 100 
per portion of 
old Middle 
Coal Meas- 
ures, - 100 
1. Shales, heavy 1. Equivalent 1. Equivalent 
sandstone and similar and similar 
and non-per- beds, : 200—400 beds, = 400-600 
sistent but 
thicker coal 
beds, - 400-500 
The lowermost division is clearly the equivalent of the 
Cherokee shales of Kansas. The variation in its thickness is 
due to the erosion unconformity between it and the underlying 
St. Louis limestone. The middle division exhibits the same 
general characteristics of thin persistent limestone and coal 
‘Loc. cit., pp. 394-398. 
