Carbon isotope data from coccolith calcite and coccolith-associated polysaccharides from sediments.

The data presented here are from: McClelland et al., 2024, Stable carbon isotope ratios of pristine carbohydrates preserved within nannofossil calcite. Geochim. Cosmochim. Acta, VOL, PP, DOI. The data include carbon isotope values of coccolith calcite and coccolith-associated polysaccharides from sediment samples, from ODP Site 1123 (Expedition 181), which is located on Chatham rise, east of New Zealand in the southernmost Pacific, from the period approx. 190ka to 105ka. All carbon isotope values are reported as delta values, relative to the VPDB calcite standard. Uk37′ and TEX86 values from contemporaneous sediments are generated and interpreted using established techniques. In the isotopes file, data are provided for two different size fractions of coccolith, which were separated into two near monospecific fractions, 2-3um and 8-12um. Carbon isotopic compositions of the calcite were measured using a VG Isogas Prism II mass spectrometer with an on-line VG Isocarb common acid bath preparation system in the Department of Earth Sciences, University of Oxford, UK. Samples were dosed with acetone and dried at 60oC for at least 30 minutes. In the instrument they were reacted with purified phosphoric acid at 90oC. Calibration to PDB standard was via the international standard NBS-19 using the Oxford in-house (NOCZ) Carrara marble standard. The purified CAP samples were measured on a Thermo Delta Plus Advantage stable isotope mass spectrometer, with Spooling Wire Microcombustion (SWiM) interface at Harvard University. The SWiM interface allows measurement of ng scale samples. A detailed description of the equipment and protocol is given in Sessions, et al. (2005; doi:10.1021/ac051251z). Organic carbon measurements made in Harvard were calibrated for consistency with measurements made in Oxford, using an apple pectin standard in a dilution series. For the isotopic analysis of CAP samples, a mass-balance correction was applied to account for the size and isotopic composition of the background. (See McClelland et al., 2024 for details of calculation and description of blanks).

本数据集所展示之资料源自于 McClelland 等人（2024年）的研究成果，其内容涉及原始碳水化合物中纳米化石方解石所保存的稳定碳同位素比值。该研究发表在《地球化学与宇宙化学学报》（Geochim. Cosmochim. Acta）上。数据集涵盖了来自沉积样品的翼足石方解石及其相关多糖的碳同位素值，这些样品取自位于新西兰东部最南太平洋查塔姆隆起的ODP站1123（探险181号）。研究时段大约介于190ka至105ka之间。所有碳同位素值均以相对于VPDB方解石标准的δ值形式报告。同时期沉积物中的Uk37′和TEX86值通过既定技术生成并解读。在等位素文件中，提供了两种不同尺寸的翼足石颗粒的数据，这些颗粒被分离成两个近乎纯种的比例，分别为2-3微米和8-12微米。方解石的碳同位素组成是通过牛津大学地球科学系使用的VG Isogas Prism II质谱仪及在线VG Isocarb通用酸浴制备系统进行测量的。样品以丙酮处理并在60°C下干燥至少30分钟。在仪器中，它们与纯化的磷酸在90°C下反应。通过国际标准NBS-19及牛津校内（NOCZ）卡拉拉大理石标准对PDB标准进行校准。纯化的多糖样品在哈佛大学使用Thermo Delta Plus Advantage稳定同位素质谱仪，配备Spooling Wire Microcombustion（SWiM）接口进行测量。SWiM接口使得ng量级样品的测量成为可能。设备与实验规程的详细描述可见 Sessions 等人（2005年；doi:10.1021/ac051251z）。在哈佛进行的有机碳测量与牛津的测量结果进行校准，以确保一致性，校准过程中使用了稀释系列中的苹果果胶标准。对于多糖样品的同位素分析，应用了质量平衡校正，以考虑背景的大小和同位素组成。（有关计算及空白描述的详细信息，请参阅 McClelland 等人，2024年）。