276 RECORD OF DEEP- WELL DRILLING FOR 1905. 
Feet. 
Oil sand and thin beds of rock, mixed 1 , 350-1 , 387 
Sand 1, 387-1, 430 j 
Gumbo. 1, 430-1, 432 
Rig used, rotary. Casing used, 12-inch to 4-inch; 1,270 feet of 4-inch; strainer, 163£ 
feet long, with boot leg at 1,224 feet. Well gushed and flowed for sixty days. Initial 
yield, 5,000 barrels in twenty-four hours. Yield in one year, over 100,000 barrels. Was 
pumping 100 barrels daily in March, 1906. 
1635. Well near Westfield, Harris County. 
[Well begun November 10, 1905; completed November 26, 1905. Authority, Harry A. Roberts, driller. 
Incomplete series of samples preserved.] 
This log of a well in northern Harris County gives more details than the logs of many 
of the wells put down in the oil fields of Louisiana and Texas. "Gumbo," a word fre- 
quently used, means sticky clay. "Rock" may be thin layers of sandstone or limestone. J 
Some of the beds of sand contain strata consolidated enough to be sandstone. 
The formations penetrated by this well are of Quaternary and Tertiary age and include 
the Columbia sands (Pleistocene), Lafayette sands, and the underlying beds of clay, sand j 
sandstone, and limestone of undetermined age, which have been correlated with the Grant ^ 
Gulf of Alabama and Mississippi. 
The character of these format ions and the occurrence of oil in the various pools is describe* 
in Bulletin No. 282, "Oil fields of the Texas-Louisiana Gulf coast," by N. M. Fenneman. i 
Record of well No. 3, on Dunn farm, 3 miles northeast of Westfield. 
Feet. 
Soft red and yellow clay and sand 0- 4 1 
Soft white sand; water-bearing 43- { I 
Soft yellow clay, solid formation . 62— li 
Soft white sand; water-bearing 129-11 1 
Soft yellow clay 139-1 
Soft white sand; water-bearing. 151-1 . 
Soft yellow clay 161-1 
Soft white sand; water-bearing 1 98-2 
Soft red and yellow clay, mostly red 215—5 J 
Soft gray sandstone 296-' 
Soft white sand; water-bearing 298-.' I 
Medium-hard gray marl 312-.' I 
Soft gray shaly sandstone 359- 
Soft gray marl 362- 
Medium-hard gray limestone 366- 
Medium-hard dark-gray marl containing much sand 370- 
Very hard dark-gray rock, called " quartzite " by driller 388* 
Medium-soft red and gray gumbo 390- 
Hard white rock 410 
Medium-soft gray gumbo . 413 
Very hard rock 422 
Medium-soft gray gumbo 425 VM 
Medium-soft gray sandstone 440 $m 
Medium-soft gray gumbo with intermingled sand 442 
Medium-hard gray rock 46( |2 
Medium-soft gray gumbo 46S f 7 
Soft white sand; water-bearing 49' -: 7 
Medium-hard white sandstone 51' JQ 
Soft white sand: water-bearing 52' ■$ 
