摘要
海水中往往含有一定量的溶解CO2（以HCO3^-存在），其δ^13C值组成十分恒定，一般在0‰值附近。赋存在海底沉积物中的孔隙水往往含有比海水更高的溶解CO2含量，且其碳同位素组成变化极大。对这些溶解CO2的碳同位素组成进行分析，能够为我们了解海底沉积物沉积一成岩过程和生物地球化学过程提供十分丰富的信息。为此，开展了沉积物孔隙水中溶解CD2（DIC）的碳同位素分析方法的研究。
An analytical method for measuring carbon isotopic compositions in dissolved inorganic carbon in pore waters from marine sediments is established. The instrument used is a Delta Plus XP stable isotope mass spectrometer coupled with on-line Gas Bench. In general, 0.5 mL of water samples is taken and reacted with pure H3PO4 in a glass vial, then the produced CO2 is transferred into the mass spectrometer and δ^13C values are obtained. Three in-house laboratory water standards have been prepared and their carbon isotope ratios are measured. Standard NJWCS-1 shows a δ^13C value of （ -8.05 ± 0.04）‰ （n =2）. Standard NJWCS-2 has a δ^13C value of （ - 19.78 ± 0.21） ‰ （ n = 10）, and Standard NJWCS-3 has a δ^13C value of （ - 5.83 ± 0.81 ） ‰ （ n = 8）. Three pore water samples taken from marine sediments in the South China Sea have been analyzed for their δ^13C of dissolved inorganic carbon, and the results are very promising. In summary, the analytical method established by the authors can be applied not only in pore waters of marine sediments but also in other nature waters such as river water, lake water, underground water, and oil field water.
出处
《地球学报》
EI
CAS
CSCD
北大核心
2005年第B09期51-52,共2页
Acta Geoscientica Sinica
基金
本文由国家863项目（编号：2003AA611020/02）资助.
