RIASSUNTO
The Miley Oil Co.'s Athens No. 6, completed at 7591 ft., is the deepestproducing oil well in the world as well as the deepest hole ever drilled withthe rotary. The importance of this well lies in the fact that it was not afreak hole drilled with special equipment at terrific cost to break records,but that it was just a part of the day's work. The derrick and machinery weresimilar to dozens of other rigs, the drillers were the same men that had beendigging 4000-ft. holes, and the careful supervision of Superintendent Allisonwas the same that the rotary seems to require at all depths. The formationspenetrated were not particularly hard and were of the same type found in mostof the fields in the Los Angeles Basin. Drilling was completed in LowerPliocene, with no indication of approaching the Miocene. This tends to showthat the ultimate depth of drilling in many parts of the Los Angeles Basin willbe determined by mechanical rather than geological considerations.
Details of Equipment and Procedure
Two hundred and thirty days were consumed in completing Athens No. 6, ofwhich 172 were actual drilling days, thus maintaining an average of 44 ft. perdrilling day. Only Hughes ""Simplex"" rock bits were used below 4526 ft.,no twist-offs occurring past this point. One hundred and fifty-four cores weretaken, yielding a total of 1067 ft. drilled, an average of 6.9 ft. per run.Seven hundred and forty feet of core were extracted, an average of 4.8 ft. perrun, the percentage of recovery being 69.2 per cent. The Elliott Core DrillingCo. Alco type barrel was used. The average time per round trip at depths in theneighborhood of 7000 to 7500 ft. was 7 hr. The minimum time recorded for acomplete round trip was 5 hr. 20 min. at a depth of about 7300 ft. The totalcost of the well, including tanks, traps and all production equipment, was$170,423.67.
Production difficulties proved to be mostly imaginary. Seventy-five hundredfeet of 2 1/2-in. tubing with a flow device at 7000 ft., through which dry gasis infused at a pressure of 300 lb., is sufficient to lift the 100 bbl. of 36.0gravity oil of which the well is at present capable.