样品预处理对有机碳同位素分析结果的影响  

SAMPLE-PRETREATMENT EFFECTS ON ANALYTICAL RESULTS OF ORGANIC C-ISOTOPES

作　　者：王金权[1] 

机构地区：[1]中国科学院南京地质古生物研究所,南京210008

出　　处：《古生物学报》2005年第3期472-477,共6页Acta Palaeontologica Sinica

基　　金：国家重点基础研究发展规划项目(G2000077700);中国科学院资源环境领域知识创新工程重大项目(KZCX2116)资助课题。

摘　　要：文中主要阐述样品预处理方法不同对于有机碳同位素分析结果将产生重要影响,并直接关系到由此而得出研究结论的可靠性。分析样品采自扬子地台震旦纪蓝田组剖面,并对相同岩石样品采取两种不同的预处理方法。分析结果显示,得到的两套数据之间存在明显的差值。这种分析差主要是来源于分析样品中残存的碳酸盐。因此,在对全岩分析样品实施有机碳同位素测定之前,务必将分析样品中无机碳除尽。此外,针对目前应用于有机碳同位素分析的样品预处理方法可能存在的问题提出看法。In general, the determined δ 13C values of organic matter in sedimentary rocks are affected by two aspects: 1) factors affecting the organic C-isotope fractionation, for example, the different types of organisms, the physical and chemical conditions of the ocean environment, including water depth, water dynamics, oxygen content, temperature, CO2 concentrations, decomposition of organic matter, and later diagenesis; and 2) analytical method, in particular, sample-pretreatment before determining δ 13C values of organic matter in sedimentary rocks.This paper mainly discusses sample-pretreatment effects on analytical results of organic Cisotopes. Atpresent, two sample-pretreatment methods are often used in the organic C-isotope analysis, which are whole-rock sanalysis and Soxhlet Extraction Method, respectively. The whole-rocks analysis for the organic C-isotopes in the late Neoproterozoic Lantian Formation sedimentary rocks shows that rock samples must be treated with hydrofluoric and hydrochloric acid (HCl 50% and HF 15%,by volume) to remove carbonate before determiningδ13 C values of the total organic matter in rock-samples, otherwise, without using HCl 50% and HF 15%,as the present test proven it most likely yields great analytical errors(Table Ⅰ in Chinese test).

关 键 词：有机碳同位素 分析结果 样品预处理 预处理方法 分析样品 碳同位素分析 同位素测定 扬子地台 岩石样品 可靠性 蓝田组 震旦纪 碳酸盐 无机碳 剖面 全岩 

分 类 号：P597[天文地球—地球化学]