290 
FLORIDA STATE GEOLOGICAL SURVEY. 
soft clayey carcareous material to a hard limestone rock. This change 
occurred within a radius of twenty or thirty feet. This stratum con¬ 
tains a few fossils preserved as casts and molds. Occasional chunks 
or layers occur which contain fairly well preserved fossils. The top 
surface of this stratum is clearly eroded uneven and represents an 
erosion unconformity. This is shown in every section observed, both 
where the stratum is soft and clayey and where it is a hard lime¬ 
stone. 
On top of this stratum is usually found a conglomerate layer con¬ 
sisting of bones and pebbles. This stratum is not invariable, but traces 
of it can usually be found. In some places it js from one to two feet 
thick. 
Lying on the bone pebble stratum is a sandy or sometimes clayey 
stratum becoming distinctly peaty above. This stratum is rarely if 
ever absent, although it varies in thickness, both as to the thickness 
of the peat and the thickness of the clayey or sandy lower part. Above 
this is the surface sand, usually loamy, and from one to two feet 
thick. 
Immediately underlying the fullers earth stratum is a close grained 
marly limestone. This limestone contains a few fossil shells preserved 
as molds. Occasionally as determined from a well near the pit, in¬ 
durated chunks or layers contain somewhat better preserved molds 
and impressions. The top of this limestone, where seen, was so far 
as could be determined, level. The break between the limestone and 
the fullers earth is distinct, but indicates, apparently, merely a change 
of conditions, and probably does not represent an unconformity. 
The fullers earth stratum is variable in thickness. Where worked 
it is 6^4 to 7 feet thick, elsewhere it thins and may disappear. Such 
an interruption of the stratum occurs between the east and the west 
pit. 
The following section was obtained in the Atlantic Refining Com¬ 
pany’s pit: 
Section in Pit of Atlantic Refining Company. 
7. . Dark colored sandy soil . 1 foot. 
6. Dark carbonaceous stratum .. 1 foot. 
5. Bone stratum containing manatee ribs and other bone fragments... 2 feet. 
4. Unconformity. 
3. Sandy calcareous stratum with gravels . 4 feet. 
2. Fullers earth . 8 feet. 
1. Close grained marl. 
The fullers earth lies apparently conformable upon this marl. 
