178 
FLORIDA STATE GEOLOGICAL SURVEY. 
Olive green calcareous sandy clay ... 435 -455 
Light sandy marl ... 455 -455J4 
Green sandy marl . 455^4-462 
Dark sandy clay . 462 -490 
Very hard dark or gray sand rock . 490 -493 
Silicified and very hard shell rock with siliceous phos- 
phatic pebbles. After passing through this rock the 
flow is increased to 112 gallons per minute, tem¬ 
perature 71 degrees F. 493 -498 
Light colored marl . 498 -500 
]Jard rock ..... 500 -506 
Light gray sandy calcareous rock with black phosphatic 
pebbles . 506 -510 
Feet. 
Light colored fossiliferous limestone (Vicksburg). Upon 
reaching this formation the flow is increased to 200 
gallons per minute. At 625 to 635 feet the harder 
stratum was drilled through, which flowed 500 gallons 
per minute, temperature 74 degrees F. At 680 feet the 
water pressure measured, as shown by the gauge, 12 
pounds . .510-680 
Limestone, prevailing brownish in color, and as a rule hard¬ 
er than above. Occasional thin layers of marl and 
shell. Slight increase of flow at 780, water pressure at 
900 feet 15 pounds; flow about 900 gallons per minute; 
temperature 74 degrees F .680-900 
Limestone similar in character to above, but as a rule not 
so hard. Flow at 980 feet, 1,500 to 2,000 gallons per 
minute . 900-980 
The Vicksburg Limestone was reached in this well at a depth 
of about 510 feet. The first 170 feet of the Vicksburg is prevail¬ 
ingly light colored or white and fossiliferous. Below 680 feet 
the limestone is as a rule brownish in color, compact and harder 
in texture and not so fossiliferous. The amount of flow, the 
pressure and the temperature increased as the deeper layers of the 
Vicksburg Limestone were penetrated. 
The formations lying above the Vicksburg Limestone can 
scarcely be differentiated. The Jacksonville formation, Miocene, 
is reached at the depth of 33 feet. At‘about 320 feet some clays 
resembling fuller’s earth were obtained. At from 415 to 420 feet 
light colored clayey limestones were encountered. With these 
