104 CEMENT MATERIALS AND INDUSTRY. [bull. 2 
30 feet of chalk marl into the overlying blue-clay marl. The bl 
marl is continuous for 175 feet to the base of the Saratoga chalk ma 
The middle portion of this chalk is exposed in the large mour 
which is surrounded by the bottom land of Plum Creek, in the cen 1 
of the SE. i of SW. i sec. 21, T. 11 S., R. 27 W., on Mr. J. E. Jol 
son's place. Here also the chalk has been quarried, giving fr€ 
exposures of the rock. Analysis 12 (p. Ill) is of fresh chalk tak 
from this quarry, and is nearly the same as that from the quarry 
the Whitecliffs Cement Works. 
The lower sandy member of the chalk is freshly exposed in i 
head of the large drainage ditch near the middle of the west side of i 
SW. i of NW. i sec. 22, T. 11 S., R. 27 W. Analysis 14 of this ch 
is practically the same as No. 6, which is of a specimen from the lov 
sandy member in the cliff at Whitecliffs Landing. 
The upper and purer chalk member is well exposed in the ditcl 
and chalk barrens on the lower ridge across the SW. i of NE. \ s 
22, T. US., R. 27 W. 
The easternmost exposure of the chalk south of Plum Creek is 
the SE. i sec. 14, T. 11 S., R. 27 W. Here the chalk barrens in i 
slopes of the hill show the upper edge of the chalk and the succeed] 
chalk and clay marl for 50 feet above the creek bottom. 
SARATOGA FORMATION. 
The Saratoga chalk, as explained previously, occurs nearly 200 f 
above the Whitecliffs chalk and is separated from it by more cla^ 
beds. 
This formation has a maximum thickness of about 50 feet wh 
complete sections have been found. The nature of the deposit vai 
only slightly from top to bottom, and there is but little change 
character along its outcrop from the vicinity of Saratoga near W 
Saline River, in Hempstead County, to Little Deciper Creek n 
Arkadelphia, in Clark County. The Saratoga marl is not knowr 
this region west of West Saline River, because of erosion and of c 
cealment by Neocene gravel and sand in the highlands and by Pic 
tocene alluvium and silt in the lowland and river bottoms. 
General section of the Saratoga chalk marl. 
1. Continuing upward from 2 the chalky rock becomes more sandy through 
imperceptible grades to limy greensand at the top of the formation. 
Analyses from the chalk near the central part of this member show it 
to contain from 40 to 50 per cent of silica 2( 
2. Generally even-textured chalky marl, which contains less sand than the 
beds higher in the formation. Chemical analyses of chalk from this bed 
show it to contain about 31 per cent of siliceous matter. The sand in 
this marl is perceptibly finer and the rock is more chalky in appearance 
than in other parts of the formation ll 
