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This paper deals with monoterpinenese in Oldnawa Trough sediments, which have been identified by TLC and GC-MS-DS. Three kinds of monoterpinene have been recognized:cyclohexene, I-methyl-3- ( 1-methylethenyl ), cyclohexene, 1-methylethenyl-5- ( 1 -methylethenyl )and cyclohexene, 1-methyl-4-(1-methylethylidene). These monoterpinenes are considered to have been derived from terrigenous higher plant detritus and are recognized as a new type of terrigenous markers. 相似文献
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石油,虽早已被人们所利用,年产量约30亿吨,但其成因问题到目前为止,仍是议论纷云。最初是以无机成因说占优势,继而又以有机成因说占主导。目前国内外仍以有机成因说占统治地位。但有机成因说却存在着难以解释的问题。本文试就这个问题进行初步的探讨,并提出石油无机成因的模式。 相似文献
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Ten stenols and stanols were identified by TLC , GC and GC-MS-DS in a marine sediment core from Beibu Bay , the South China Sea .C27, C28 and C29 A5 stenols and 5a- stanols mainly come from zoopiankton, algae and phytoplankton in marine environment. C29 24-ethylcholest- 5 - en- 3B- ol is thought to indicate input of terrigenous organic matter . The increase of C27 . C28 and C29 5a-stanol /5 stenol ratios with sediment depth shows the evolution of stenols and stanols in the marine sediment core . 相似文献
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Compositional data on the sterol and alcohol fractions isolated from deep-sea marine sediments from the Okinawa Trough were obtained to determine the relative contribution from. marine and terrestrial inputs. Following extraction, the sterol plus alcohol fraction was isolated by layer chromatography, derivatized with BSTFA and then analysed by capillary GC and GC-MS. A suite of C26-C29 stenols and stanols and C30-C32 keto - alcohols were identified in the sediments. The thermal stability of the compounds in these sediments was studied by heating portions of the surface sediment in glass tubes fpr 16 hours at temperatures from 50℃ to 200℃.The C27 stanol/stenol ratio increased when temperatures went up to 175℃ , but the distribution of C30-C32 Keto - alcohols remained unaffected. At 200℃ most of the sterols and Keto - alcohols were destroyed. 相似文献
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南黄海北部沉积物有机质在上部层位损失较少,其有机地球化学主要特征为:(1)有机碳与沥青含量随粒度变细而增高;(2)有机质的损失与粒度紧密相关,在粘土沉积物中几乎无损失;(3)沥青和烃类含量都很低,沥青有几百个ppm,而烃类只有几十个ppm。 相似文献
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Examination of solvent-extractable lipids in sediments from Beibu Gulf, South China Sea by capillary gas chromatography (GC) and capillary gas chromatography-mass spectrometry (GC-MS) resulted in the first identifications of β,γ-carotanes and their C19 to C31 homologs in the modern sediments from the China Seas. Distributional features of these ( mainly triterpenoid and steroid hydrocarbons) biomarkers are discussed and the possibility of using these compounds as indicators of source of materials, diagenesis and depositional conditions is explored. It was found that the biomarkers in this region are mixtures of allochthonous (terrigenous and / or crude oil leak or pollu -tion) and autochthonous (marine) organic components. The biomarkers have proved to be of value for understanding sedimentation . 相似文献