The values and distribution patterns of the strontium (Sr) isotope ratio ${}^{\mathrm{87}}\mathrm{Sr}{/}^{\mathrm{86}}\mathrm{Sr}$ in Earth surface materials are of use in the geological, environmental, and social sciences. Ultimately, the ${}^{\mathrm{87}}\mathrm{Sr}{/}^{\mathrm{86}}\mathrm{Sr}$ ratios of soils and everything that lives in and on them are inherited from the rocks that are the parent materials of the soil's components. In Australia, there are few large-scale surveys of ${}^{\mathrm{87}}\mathrm{Sr}{/}^{\mathrm{86}}\mathrm{Sr}$ available, and here we report on a new, low-density dataset using 112 catchment outlet (floodplain) sediment samples covering 529 000 km² of inland southeastern Australia (South Australia, New South Wales, Victoria). The coarse (<2 mm) fraction of bottom sediment samples (depth ∼ 0.6–0.8 m) from the National Geochemical Survey of Australia were milled and fully digested before Sr separation by chromatography and ${}^{\mathrm{87}}\mathrm{Sr}{/}^{\mathrm{86}}\mathrm{Sr}$ determination by multicollector-inductively coupled plasma mass spectrometry. The results show a wide range of ${}^{\mathrm{87}}\mathrm{Sr}{/}^{\mathrm{86}}\mathrm{Sr}$ values from a minimum of 0.7089 to a maximum of 0.7511 (range 0.0422). The median ${}^{\mathrm{87}}\mathrm{Sr}{/}^{\mathrm{86}}\mathrm{Sr}$ (± median absolute deviation) is 0.7199 (± 0.0071), and the mean (± standard deviation) is 0.7220 (± 0.0106). The spatial patterns of the Sr isoscape observed are described and attributed to various geological sources and processes. Of note are the elevated (radiogenic) values ($\ge \sim$ 0.7270; top quartile) contributed by (1) the Palaeozoic sedimentary country rock and (mostly felsic) igneous intrusions of the Lachlan geological region to the east of the study area; (2) the Palaeoproterozoic metamorphic rocks of the central Broken Hill region; both these sources contribute radiogenic material mainly by fluvial processes; and (3) the Proterozoic to Palaeozoic rocks of the Kanmantoo, Adelaide, Gawler, and Painter geological regions to the west of the area; these sources contribute radiogenic material mainly by aeolian processes. Regions of low ${}^{\mathrm{87}}\mathrm{Sr}{/}^{\mathrm{86}}\mathrm{Sr}$ ($\le \sim$ 0.7130; bottom quartile) belong mainly to (1) a few central Murray Basin catchments; (2) some Darling Basin catchments in the northeast; and (3) a few Eromanga geological region-influenced catchments in the northwest of the study area; these sources contribute unradiogenic material mainly by fluvial processes. The new spatial Sr isotope dataset for the DCD (Darling–Curnamona–Delamerian) region is publicly available (de Caritat et al., 2022; https://dx.doi.org/10.26186/146397)​​​​​​​.

中文翻译：

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澳大利亚东南部内陆锶等景观

锶（Sr）同位素比值及分布规律 ${}^{\mathrm{87}}\mathrm{锶}{/}^{\mathrm{86}}\mathrm{锶}$地表材料在地质、环境和社会科学中的应用。最终，${}^{\mathrm{87}}\mathrm{锶}{/}^{\mathrm{86}}\mathrm{锶}$土壤和生活在其中和之上的一切物质的比例都是从岩石中继承下来的，岩石是土壤成分的母质。在澳大利亚，很少有大规模的调查${}^{\mathrm{87}}\mathrm{锶}{/}^{\mathrm{86}}\mathrm{锶}$可用，在这里我们报告了一个新的低密度数据集，该数据集使用 112 个集水口（洪泛区）沉积物样本，覆盖澳大利亚东南部内陆（南澳大利亚、新南威尔士、维多利亚）的^{529 000 平方公里。}来自澳大利亚国家地球化学调查局的底部沉积物样品（深度∼  0.6-0.8 m）的粗（< 2  mm）部分在通过色谱分离 Sr 和${}^{\mathrm{87}}\mathrm{锶}{/}^{\mathrm{86}}\mathrm{锶}$通过多收集器电感耦合等离子体质谱法测定。结果显示范围广泛${}^{\mathrm{87}}\mathrm{锶}{/}^{\mathrm{86}}\mathrm{锶}$值从最小值 0.7089 到最大值 0.7511（范围 0.0422）。中位数${}^{\mathrm{87}}\mathrm{锶}{/}^{\mathrm{86}}\mathrm{锶}$（± 中值绝对偏差）为0.7199（±0.0071），平均值（± 标准偏差）为0.7220（± 0.0106 ）。观察到的 Sr 等景观的空间模式被描述并归因于各种地质来源和过程。值得注意的是升高的（放射）值（$\ge ～$ 0.7270; （1）研究区东部拉克兰地质区的古生代沉积岩和（主要是长英质）火成岩侵入体贡献的最高四分位数；（2）布罗肯希尔中部古元古代变质岩；这两种来源都主要通过河流过程贡献放射性物质；(3) 该地区西部的 Kanmantoo、Adelaide、Gawler 和 Painter 地质区的元古代至古生界岩石；这些来源主要通过风成过程贡献放射性物质。低的地区 ${}^{\mathrm{87}}\mathrm{锶}{/}^{\mathrm{86}}\mathrm{锶}$($\le ～$ 0.7130; 底部四分位）主要属于（1）墨累盆地中部的几个流域；(2) 东北部的一些达令盆地流域；(3) 研究区西北部的几个受 Eromanga 地质区域影响的集水区；这些来源主要通过河流过程提供非放射性物质。DCD（Darling-Curnamona-Delamerian）区域的新空间 Sr 同位素数据集已公开（de Caritat 等人，2022；https ://dx.doi.org/10.26186/146397 ） .