Nowadays, complicated due to the increased content of clay matter structure reservoirs have been involved in the development and operation by Rosneft Oil Company. Sometimes widely used in laboratory practice (capillarimetry, routine petrophysical studies) core analysis methods treatment faces a number of significant difficulties and limitations including in extreme cases the complete impossibility of their using in the case of weakly consolidated, highly clay and oil source rocks. It is obvious that the complex terrigenous reservoirs core samples researching process faces certain difficulties, such as partial or complete destruction of samples under repeated exposure, violation of the integrity of the pore space, etc. Integration of research methods in this case is problematic. At the same time, even under such non-trivial conditions, the existing and currently developing method of laboratory NMR-relaxometry is quite capable to solving the problems of determining both the standard set of filtration – reservoir properties and specific ones-determining capillary-bound, structural (bound in clays) and free fluid, phase composition of the saturating fluid and the parameters associated with the above.
The employees of Rosneft together with employees of the laboratory complex Rosneft-NTC LLC (a subsidiary of Rosneft Oil Company) considered the possibility of using the NMR-relaxometry method for the rapid assessment of clay content of terrigenous rocks. Based on the results obtained, it can be concluded that a single experiment is applicable by the method of NMR-relaxometry where along with the determination of the above petrophysical parameters, the clay content of the rocks is estimated without additional involvement of particle size analysis data, which helps to reduce time and effort required to laboratory studies.
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