The ratio of total organic carbon to total nitrogen (TOC:TN) and the stable carbon isotope ratio of organic matter (δ13Corg) are widely applied for inferring the origin of organic matter (OM) in Quaternary marine sed...The ratio of total organic carbon to total nitrogen (TOC:TN) and the stable carbon isotope ratio of organic matter (δ13Corg) are widely applied for inferring the origin of organic matter (OM) in Quaternary marine sediments. A plot of TOC:TN vs. δ13Corg is useful for such studies but is strongly based on qualitative constraints. This study is based on the qualitative characterization of the source of Quaternary OM via analysis of TOC:TN and δ13Corg signatures, but also proposes a probability parameter, which combines both signatures, to infer the amount of Terrestrial OM Input (TOMI). This index provides a method for quantifying the proportion of terrestrial OM vs. marine OMin a more comprehensive manner. The TOMI index concept was applied to a study area in theJoetsuBasin, eastern margin of theJapanSea, where previous studies have characterized theOMfrom the Last Glacial Maximum (LGM) to the present. The upwards increase in TOC indicates thatOMproduction during the Holocene was higher than during the LGM. The enriched δ13Corg signature upwards and decrease in TOC:TN suggest predominantly marine phytoplankton OM during the Holocene. Throughout the LGM, low OM production with depleted δ13Corg values and high TOC:TN values in the sediments suggest a predominantly C3 terrestrial plant source for the OM. Using these data, it was possible to calculate a proxy for a sea level variation curve during that period and to investigate the influence of the proximity of the coastal line to the continental slope on the input of terrestrial material to the basin. The proposal provides information for the application of sequence stratigraphic concepts. The TOMI index could confirm that the proximity to the shoreline and shelf break has a strong influence on the input of terrestrial material during lowstand periods.展开更多
采用VarioTOC法测定页岩和土壤样品中的TOC,对仪器自带标样(Cat No B2152-Certificate No207835)和国家一级标准物质GBW07423、GBW07427、GBW07363进行测定,该方法的相对标准偏差3.01%~4.93%,方法的检出限为(3s)0.012%,加标回收率为96.8...采用VarioTOC法测定页岩和土壤样品中的TOC,对仪器自带标样(Cat No B2152-Certificate No207835)和国家一级标准物质GBW07423、GBW07427、GBW07363进行测定,该方法的相对标准偏差3.01%~4.93%,方法的检出限为(3s)0.012%,加标回收率为96.8%~102.6%,结果表明该方法具有很好的准确度和精密度。该测定方法与其它方法相比具有灵敏度高、干扰少、测定范围广、可操作性强等优势,适用于页岩及土壤样品中TOC的测定。展开更多
文摘The ratio of total organic carbon to total nitrogen (TOC:TN) and the stable carbon isotope ratio of organic matter (δ13Corg) are widely applied for inferring the origin of organic matter (OM) in Quaternary marine sediments. A plot of TOC:TN vs. δ13Corg is useful for such studies but is strongly based on qualitative constraints. This study is based on the qualitative characterization of the source of Quaternary OM via analysis of TOC:TN and δ13Corg signatures, but also proposes a probability parameter, which combines both signatures, to infer the amount of Terrestrial OM Input (TOMI). This index provides a method for quantifying the proportion of terrestrial OM vs. marine OMin a more comprehensive manner. The TOMI index concept was applied to a study area in theJoetsuBasin, eastern margin of theJapanSea, where previous studies have characterized theOMfrom the Last Glacial Maximum (LGM) to the present. The upwards increase in TOC indicates thatOMproduction during the Holocene was higher than during the LGM. The enriched δ13Corg signature upwards and decrease in TOC:TN suggest predominantly marine phytoplankton OM during the Holocene. Throughout the LGM, low OM production with depleted δ13Corg values and high TOC:TN values in the sediments suggest a predominantly C3 terrestrial plant source for the OM. Using these data, it was possible to calculate a proxy for a sea level variation curve during that period and to investigate the influence of the proximity of the coastal line to the continental slope on the input of terrestrial material to the basin. The proposal provides information for the application of sequence stratigraphic concepts. The TOMI index could confirm that the proximity to the shoreline and shelf break has a strong influence on the input of terrestrial material during lowstand periods.
文摘采用VarioTOC法测定页岩和土壤样品中的TOC,对仪器自带标样(Cat No B2152-Certificate No207835)和国家一级标准物质GBW07423、GBW07427、GBW07363进行测定,该方法的相对标准偏差3.01%~4.93%,方法的检出限为(3s)0.012%,加标回收率为96.8%~102.6%,结果表明该方法具有很好的准确度和精密度。该测定方法与其它方法相比具有灵敏度高、干扰少、测定范围广、可操作性强等优势,适用于页岩及土壤样品中TOC的测定。
