Data for: Stable isotope analysis of the Gwebin mammalian fauna (late Pliocene, central Myanmar) and its implication to paleoenvironmental changes in late Neogene of central Myanmar

Isotopic composition of treated samples was measured on a Gasbench II coupled to a Finnigan Delta V Mass Spectrometer at the University of South Florida. The CO2 samples were run in continuous flow mode after reaction with 103% phosphoric acid (100% H3PO4 with excess P2O5) at 25 °C for 24 hours (McCrea, 1950). Seven replicate samples of Carrara Marble (an internal standard which has been assigned a value of δ13C=+2.01‰, δ18O=−1.79‰, based on analysis with respect to NBS-19, δ13C=+1.95‰, δ18O=−2.20‰) and NBS-18 carbonatite (13C=−5.04‰, δ18O=−23.05‰, NIST, 1992) were analyzed in each run of 60 samples. Standard deviation of replicate analyses for both isotope values was 0.15‰. Stable isotope data were reported in the conventional delta () notation for carbon (13C) and oxygen (18O) relative to V-PDB (Vienna-Pee Dee Belemnite, i.e., PDB expressed in terms of NBS-19): =[(R sample/R standard)−1]×1000‰, where R denotes 13C/12C or 18O/16O. The statistical analyses were carried out using PAST (version 3.20).

经前处理后的样品同位素组成，于美国南佛罗里达大学的Gasbench II联用Finnigan Delta V Mass Spectrometer质谱仪上完成测定。二氧化碳样品在与103%磷酸（含过量五氧化二磷的100%正磷酸）于25℃下反应24小时后，以连续流模式进行分析（McCrea, 1950）。每批次分析60个待测样品时，同步测定7份卡拉拉大理石（Carrara Marble）重复样作为内标，以及NBS-18碳酸盐岩（δ¹³C=−5.04‰, δ¹⁸O=−23.05‰, NIST, 1992）作为外部标准。该内标的δ¹³C=+2.01‰、δ¹⁸O=−1.79‰，其定值基于以NBS-19为参照的分析结果（NBS-19的δ¹³C=+1.95‰、δ¹⁸O=−2.20‰）。两类同位素值的重复分析标准偏差均为0.15‰。稳定同位素数据采用常规δ记法报告，其中碳同位素（δ¹³C）与氧同位素（δ¹⁸O）的参照标准为V-PDB（Vienna-Pee Dee Belemnite，维也纳佩德白垩石，即以NBS-19为基准转换的PDB标准）：δ=[(R样本/R标准)−1]×1000‰，式中R代表¹³C/¹²C或¹⁸O/¹⁶O。统计分析采用PAST（版本3.20）完成。