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dc.contributor.authorChernova, T.G.
dc.contributor.authorParopkari, A.L.
dc.contributor.authorPikovskii, Yu.I.
dc.contributor.authorAlekseeva, T.A.
dc.date.accessioned2009-01-10T11:09:59Z
dc.date.available2009-01-10T11:09:59Z
dc.date.issued1999
dc.identifier.citationMarine Chemistry, Vol.66; 231-243p.
dc.identifier.urihttp://drs.nio.org/drs/handle/2264/1776
dc.description.abstractA study on the bulk distributions and molecular structures of n-alkanes and polycyclic aromatic hydrocarbons (PAH) in organic matter of the sediments from the Bay of Bengal and the Eastern and Central Indian Basins was underdaken. The former two regions represent areas characterised by "normal" sedimentation while the third one mainly represents a region of "active tectonism". Content of the hydrocarbons in the sediments of "normal" sedimentation ranges between 4.6 and 16.5 mu g/g and aromatic hydrocarbons ranges between 0 and 0.38 mu g/g. n-Alkanes in the sediments of the northern deep part of the Bay of Bengal consist mostly of long-chain structures (total C sub(25)-C sub(33) up to 70%) with a high carbon preference index (CPI = 3.01-3.43), indicating a large contribution of organic matter from terrigenous sources. The sediments from the Eastern Indian Basin have n-alkane distributions in which the long-chain components did not exceed 52.5% and the CPI was 1.7-1.90, indicating that the hydrocarbons are mostly derived from marine sources. Sharp increases fo hydrocarbons are found in the vicinity of the tectonically active region of the Central Indian Basin, particularly in the sediments collected from the fracture zone. The total concentration of hydrocarbons increase to 170 mu g/g and the aromatic hydrocarbons fraction to 156.3 mu g/g. The proportion of short-chain n-alkanes increases up to 70%. CPI decreases to 0.76-1.12, and high concentrations of n-C sub(16) (16-40%) occur, all of which are absent in the other samples. The molecular content of PAH includes the unsubstituted individual structures: biphenyl, fluorene, pyrene, perylene, benzo(ghi)perylene, and the groups of homologues of naphthalene, benzofluorene, phenanthrene and chrysene. The association of the PAH and composition of paraffin hydrocarbons in the surficial sediments of deformation zone indicate that these are the resultant products of hydrothermal processes. It is, therefore, suggested that the association and composition of the hydrocarbons in sediments can be utilised as a paleoceanographic parameter to decipher the history of tectonism of an area
dc.language.isoen
dc.publisherElsevier
dc.rightsCopyright [1999]. All efforts have been made to respect the copyright to the best of our knowledge. Inadvertent omissions, if brought to our notice, stand for correction and withdrawal of document from this repository.
dc.subjectsediment analysis
dc.subjectaromatic hydrocarbons
dc.subjectsedimentation
dc.subjectplate tectonics
dc.subjectactive margins
dc.subjectmolecular structure
dc.subjectdeformation
dc.subjecthydrothermal activity
dc.titleHydrocarbons in the Bay of Bengal and Central Indian Basin bottom sediments: Indicators of geochemical processes in the lithosphere
dc.typeJournal Article


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