NEW DATA ON ISOTOPIC COMPOSITION OF HYDROTHERMAL OIL FROM THE UZON CALDERA, KAMCHATKA

Abstract

The hydrothermal oil in the Uzon caldera is represented by two fractions (generations) separated in time and, partially, in space. The first generation is observed as green (rapidly turning brown in air) heavy (0.9148-0.9767 g/cm3) viscous and resinous (up to 9.3% of resin), sulfurous (up to 2%), low-paraffin (up to 2.1%) oil of the methane-naphthene-aromatic type with a uniquely high optic activity (αD = 24.2%) and extremely low degree of maturity. The second generation makes up colorless hydrocarbon condensate (with a strong kerosene smell) that rapidly spreads as iridescent films and gradually evaporates. This condensate is close to the low-density light-colored naphtha from the Bogachev field.