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Use of vhf dielectric measurements for borehole formation analysis

Journal Article · · Log Anal.; (United States)
OSTI ID:6571382

A study of the dielectric properties of sedimentary rocks at a sufficiently high frequency may provide useful data for the evaluation of borehole wall formations in exploration and production wells. An experimental program carried out between 1960 and 1967 on sandstone and limestone samples lent further support to these expectations. At frequencies above 20 Mc/s both real and imaginary parts of the complex epsilon* = epsilon' - j epsilon'' were measurable. Moreover, at higher frequencies, epsilon' proved to be independent of the salinity of the water filling the pores, and insensitive to the way in which the oil and the water are actually distributed. The value of epsilon'', on the other hand, turned out to be indicative of the prevailing salinity. By combining other logging data (for instance from an electric or porosity log) with a series of such v.h.f. measurements of epsilon' and epsilon'', the oil or water saturation, the effective formation porosity, the pore-filling fluid salinity, and the rock matrix formation factor might be deduced, if the depth of investigation can be made large enough to overcome the invasion effects.

Research Organization:
Koninklijke/Shell Exploratie en Produktie Laboratorium, Rijswijk, Netherlands
OSTI ID:
6571382
Journal Information:
Log Anal.; (United States), Journal Name: Log Anal.; (United States) Vol. 19:3; ISSN LGALA
Country of Publication:
United States
Language:
English