Development Of Standard Isotopes Of Carbon And Nitrogen Isotopes (?¹³C, ?¹⁵N) In Marine Sediments

Carbon and nitrogen stable isotope in sediments as an effective indicator of different geological period can be sensitive markers of parameters such as air,temperature and precipitation changes.The research has been widely used in the global carbon cycle,climate change and biological evolution,organic matter source and migration,the Marine ecological environment,such as stratigraphic correlation,biogeochemistry research field.Carbon and nitrogen stable isotope values in Marine sediments can effectively and accurately determine the source of the organic matter,reflect the status of terrigenous organic matter and the supply of surface water productivity.The development of the Marine sediment geochemical reference materials at China and abroad started relatively late,progress slowly.Current international general carbon isotope standard sample for the strata in the cretaceous skin DE group arrow petrochemical stone,and in nitrogen isotope analysis the nitrogen in the air has been choosen as standard.And so far there is no domestic submarine sediment carbon and nitrogen stable isotope reference materials are available.To this end,a batch of reference materials of carbon and nitrogen stable isotope from marine sediments has been developed based on ISO guide 35 and national level standard material specifications.Candidate sample in order to cover the "intertidal zone,coastal zone,deep sea area from near to far,which was collected from the Bohai Jinzhou Bay,the costal of Fujian and Zhejiang in the east part of China sea and the ocean through of Okinawa within the East China Sea,respectively.All reference materials contain certified values of 4 elements: the total carbon and nitrogen isotope(?¹³C-TC,?¹⁵N-TN)and organic carbon and nitrogen isotope(?¹³C-Corg,?¹⁵N-Norg),which was determined by an inter-laboratory comparison of 8 participating laboratories,using the method of element analysis-isotope ratio mass spectrometry?EA-IRMS?.The analytical of the uniformity test results,get the F value measured values are less than the critical value,indicate that the reference materials were homogeneous.And the stability test,calculate the fitting line of b1 was not significant,indicate that has no statistically significant instability within a year.The standard uncertainty of ?¹³C and ?¹⁵N were less than 0.15% and 0.24%,respectively,which the certified values and uncertainties was reasonable.The reference materials of natural carbon and oxygen isotope were first based on the marine sediments in China.The test method was accurate and reliable,thus we expect it can be used for instrument calibration,method evaluation and quality control in related areas such as marine,geological and environmental laboratory.