I/Ca data from Lower–Middle Ordovician carbonate strata in Baltoscandia

This dataset documents a survey of iodine-to-calcium, I/(Ca+Mg), redox proxy data from Lower–Middle Ordovician carbonate strata at various localities in Baltoscandia. Samples derive from Grönhögen, Horns udde, Hällekis, Killeröd, Knivinge, Kårgärde, Lanna, Lyckhem, and Skärlöv in Sweden; Uuga cliff and Väo in Estonia; Lynna River in western Russia. The I/(Ca+Mg) analyses were done to explore spatiotemporal variability in marine shelf oxygen conditions across the Baltoscandian palaeoshelf during the Early through Middle Ordovician. Sample preparations and analyses were done following established I/(Ca+Mg) methods, using an Agilent 7500cs inductively coupled-plasma mass spectrometer. The I/(Ca+Mg) data indicate progressive oxygenation of the Baltoscandian palaeoshelf during the studied time interval.

本数据集记录了波罗的地盾（Baltoscandia）多个地点下-中奥陶统碳酸盐岩地层中的碘钙比（I/(Ca+Mg)）氧化还原代用指标数据。样品采自瑞典的格罗讷霍根（Grönhögen）、霍兹乌德（Horns udde）、赫勒基斯（Hällekis）、基勒勒德（Killeröd）、克尼温厄（Knivinge）、卡尔盖尔德（Kårgärde）、拉纳（Lanna）、利克赫姆（Lyckhem）和斯克尔洛夫（Skärlöv）；爱沙尼亚的乌加崖（Uuga cliff）和韦奥（Väo）；以及俄罗斯西部的林纳河（Lynna River）。本次碘钙比分析旨在探究早奥陶世至中奥陶世期间，波罗的地盾古陆架上海域陆架氧含量条件的时空变化特征。样品前处理与分析均遵循成熟的碘钙比分析方法，采用安捷伦（Agilent）7500cs型电感耦合等离子体质谱仪完成。碘钙比数据表明，在本次研究的时间区间内，波罗的地盾古陆架发生了逐步的氧化作用。