Organic Matter in the Thermal Waters of the Paratunka Geothermal Field, Kamchatka

Abstract The first data on the composition of organic compounds in thermal waters have been obtained from deep boreholes in the Paratunka geothermal field in Kamchatka. A variety of organic compounds belonging to eleven homological series were identified by capillary gas chromatography–mass spectrometry and solid phase extraction. The thermal waters were found out to be strongly dominated by aromatic and aliphatic hydrocarbons (HC), which were formed in relation to both thermogenic processes (transformation of organic residues under the effect of high temperatures and pressures) and bacterial activity. The Karymshina thermal waters are characterized by a specific molecular mass distribution of HC and contain only even-normal alkanes. It is shown that the composition of organic compounds of medium volatility in the Paratunka geothermal field is similar to the composition of organic matter (OM) in other thermal water occurrences of the Kamchatka Peninsula (Mutnovka and Uzon geothermal fields), which have been previously studied using the same methodology: all the waters are characterized by the prevalence of aliphatic and aromatic HC over other identified compounds.