Bituminological parameters of sediments from the Central Indian Ocean

Use of bituminological parameters for determining origin of organic matter in sediments from the deformation zone in the Central Indian Ocean is considered. It is shown that relatively high concentrations of hydrocarbons enriched in aromatic structures (above 60%) were detected in bitumoids from the region of extensive tectonic deformations of the sedimentary cover. The main molecular structures of polycyclic aromatic hydrocarbons (PAH) are homologues of naphtylene (40-60% rlt.), and phenanthrene (15-40% rlt.), biphenyl (19-30% rlt.) and benzfluorene homologues (up to 13% rlt.). Pyrene, 1.12-benzperylene, and chrysene homologues are found in minor amounts. Such distribution of PAH is close to that in carbonic matter of high-temperature hydrothermal associations. It is shown that sediments from fracture zones and from boundaries of deformed blocks contain organic components of deep high-temperature origin.