LUMINESCENCE LOGGING 327 



Observation consisted in immersing the window in the clay suspension and 

 slowly moving the whole apparatus along the bath; every 5 to 10 cm the 

 instrument was stopped and the intensity of the luminescence was measured. 

 Values of intensity were obtained as a result of the measurements (Fig. 10). 

 It can be seen that, in going from the clay suspension containing petroleum 

 to the ordinary suspension, the petroleum ceases being detected at a distance 

 of roughly 10 cm; with the Plexiglas window, on further displacement of 

 the apparatus, the petroleum is washed from the window very poorly. 



CONCLUSIONS 



1. An apparatus for studying the luminescence of samples of drilling 

 fluid allows petroleum present in the fluid to be detected at concentrations 

 down to 0.5 cm^/1. 



Thus device may serve as a basis for automatizing tlie process of lumines- 

 cence logging according to the drilling fluid. 



2. Study of the spectral characteristics of the luminescence makes it 

 possible in most cases to distinguish between the luminescence arising from 

 the petroleum in the bed and the luminescence arising from lubricating 

 materials that have fallen into the drilling fluid. 



REFERENCES 



1. A. A. Il'ina, Study of dispersed and concentrated types of bitumens by spectral and 



chemical methods. Report on topic No. 50. Documents VNIGNI (1954). 



2. M. Kh. Kleinaian, Distinguishing petroleum from oils and resins and determining 



the content of bitumen in a core sample and in drilling fluid. Razvedka nedr. No. 6, 

 (1941). 



3. M. A. Konstantinova-Shlezinger, Luminescence analysis. Izd. Akad. Nauk SSSR. 



(1948). 



4. P. A. Levshunov, Oil and gas logging. Exploratory and production geophysics, 



Ed. 2. Gostoptekhizdat (1950). 



5. V. N. Florovskaya, An introduction to luminescence bituminology. Gostop- 



tekhizdat (1946). 



6. V. N. Florovskaya, Luminescent-bituminological method of studying and prospecting 



for petroleum deposits. Gostojitekhizdat (1954). 



7. F. M. Efendiev and E. I. Mamedov, Spectroscopic investigation of the luminescence 



of petroleum. Izd. Akad. Nauk Azerbaidzhan SSR, No. 1, (1952). 



