The preparation and characterisation of three new sediment‐based reference materials SdAR‐L2 (blended sediment), SdAR‐M2 (metal‐rich sediment) and SdAR‐H1 (metalliferous sediment) described in this paper involved collaboration between the United States Geological Survey (USGS) and International Association of Geoanalysts (IAG). Sediments and soils from six locations in the western United States were mixed according to a USGS‐designed blending programme that calculates the proportions of source materials required to match target mass fractions and minimise the number of elements with mass fractions below instrument detection limits. For selected element mass fractions, NIST SRMs 2709–2711 provided target values. By using this approach, the three reference materials retained a natural mineralogy that is so essential for matching matrix and dissolution characteristics. Geochemical characterisation of these materials was carried out through the IAG GeoPT proficiency testing programme. Three independent rounds of GeoPT testing were used, each providing results from over eighty laboratories. Contributed results were statistically evaluated to produce reference values for over forty elements in each material. Reference and information values as well as mineralogical compositions are presented to establish these samples as reference materials, especially for use in mineral exploration and environmental contamination monitoring studies.

中文翻译：

---

三种用于矿物勘探和环境污染研究的新型地球化学参考材料：SdAR‐L2，SdAR‐M2和SdAR‐H1

本文描述的三种新的基于沉积物的参考物质SdAR-L2（混合沉积物），SdAR-M2（富金属沉积物）和SdAR-H1（含金属沉积物）的制备和表征涉及美国地质调查局（美国地质勘探局（USGS）和国际地质分析家协会（IAG）。根据美国地质调查局设计的混合程序，对美国西部六个地点的沉积物和土壤进行了混合，该程序计算出与目标质量分数相匹配并最小化质量分数低于仪器检测极限所需的元素数量所需的原料比例。对于选定的元素质量分数，NIST SRM 2709–2711提供了目标值。通过使用这种方法，这三种参考物质保留了天然矿物学，这对于匹配基质和溶解特性至关重要。这些材料的地球化学表征是通过IAG Geo进行的PT能力测试计划。使用了三轮独立的Geo PT测试，每轮都提供了80多个实验室的结果。对贡献的结果进行统计评估，以产生每种材料中40多种元素的参考值。提供参考和信息值以及矿物成分，以将这些样品建立为参考材料，特别是用于矿物勘探和环境污染监测研究。