The possibility is shown of establishing the degree of conversion of r
esidual oils, formed as a result of using hydrodynamic methods to incr
ease oil production, for the case of a number of areas of the Romashki
nsk field on the basis of comparing their composition with oils produc
ed from deposits of various ages, with natural and oxidized bitumens,
and also with petroleum impurities after biochemical recultivation mea
sures.