Abstract Portable energy-dispersive X-ray fluorescence (PXRF) analyzers are routinely used to generate large elemental datasets in sedimentary strata. These data provide the basis for assessing stratigraphic changes in geochemistry, bulk mineralogy, and paleo-redox conditions. The manufacturer provided procedure used to calculate elemental concentrations from PXRF photon counts that was developed for siliciclastic mudrocks. This quantification is, however, routinely applied to other sedimentary rocks, such as carbonates, which often have very different elemental concentrations and rock textures. The current study reports elemental concentration data from 57 limestone and dolomite rock samples measured by both PXRF and conventional geochemical analyses including inductively coupled plasma-mass spectrometry (ICP-MS), inductively coupled plasma - optical emission spectrometry (ICP-OES), and wavelength-dispersive X-ray fluorescence (WD-XRF). Carbonate samples were subdivided into two groups. The calibration set (N = 43) is used to establish a carbonate-specific PXRF quantification procedure, and to investigate the effects of different sample preparation techniques. The validation set (N = 14) is used to evaluate the applicability of both the newly developed carbonate-specific quantification procedure and the existing mudrock quantification procedure for the carbonate rock suite. PXRF measured photon counts in the calibration set exhibit strong positive linear correlations (R2 = 1–0.76) with the elemental concentrations independently measured from ICP-MS and/or ICP-OES, and WD-XRF. These linear relationships were used to calculate elemental concentrations in the validation set, which were then statistically compared with the measured elemental concentrations. Results of the carbonate-specific quantification procedure show that 13 elements (Mg, Al, Si, P, K, Ca, Ti, Mn, Fe, Rb, Sr, Y, and Zr) in the carbonate validation set are quantified with PXRF at the definitive data quality level. The mudrock-based quantification procedure, in contrast, quantified only 4 elements at the definite data quality level (Si, K, Ca, and Zr), suggesting that carbonate-specific calibration should be used to ensure higher data quality. The results from the sample preparation experiments exhibit different linear regressions for whole rock, loose powders, pressed powder pellets, and fused discs. The results of this study show that (i) PXRF can reliably identify and accurately quantify the concentrations of 13 common rock-forming elements in carbonate rocks; (ii) the carbonate-specific quantification procedure provides a higher level of data quality for carbonate rocks compared to the mudrock-based quantification; (iii) carbonate rock samples are inherently heterogeneous and thus require more intensive sample preparation and advanced statistical methods to account for this in the quantification procedure; and (iv) the matrix effect that results from different sample preparations must be accounted for in the quantification procedure.

中文翻译：

---

从便携式能量色散 X 射线荧光 (PXRF) 数据确定元素浓度的新碳酸盐特定量化程序

摘要 便携式能量色散 X 射线荧光 (PXRF) 分析仪通常用于生成沉积地层中的大型元素数据集。这些数据为评估地球化学、大块矿物学和古氧化还原条件的地层变化提供了基础。制造商提供了用于根据为硅质碎屑泥岩开发的 PXRF 光子计数计算元素浓度的程序。然而，这种量化通常应用于其他沉积岩，例如碳酸盐，它们通常具有非常不同的元素浓度和岩石质地。目前的研究报告了 57 个石灰岩和白云岩岩石样品的元素浓度数据，这些数据通过 PXRF 和传统地球化学分析（包括电感耦合等离子体质谱法 (ICP-MS)）、电感耦合等离子体 - 发射光谱 (ICP-OES) 和波长色散 X 射线荧光 (WD-XRF)。碳酸盐样品被细分为两组。校准集 (N = 43) 用于建立特定于碳酸盐的 PXRF 量化程序，并研究不同样品制备技术的影响。验证集 (N = 14) 用于评估新开发的碳酸盐特定量化程序和现有泥岩量化程序对碳酸盐岩套件的适用性。校准集中的 PXRF 测量光子计数与从 ICP-MS 和/或 ICP-OES 以及 WD-XRF 独立测量的元素浓度显示出很强的正线性相关性 (R2 = 1–0.76)。这些线性关系用于计算验证集中的元素浓度，然后将其与测量的元素浓度进行统计比较。碳酸盐特定量化程序的结果表明，碳酸盐验证集中的 13 种元素（Mg、Al、Si、P、K、Ca、Ti、Mn、Fe、Rb、Sr、Y 和 Zr）在确定的数据质量水平。相比之下，基于泥岩的量化程序在确定的数据质量水平（Si、K、Ca 和 Zr）仅量化了 4 种元素，这表明应使用碳酸盐特定校准来确保更高的数据质量。样品制备实验的结果显示了整块岩石、松散粉末、压粉球团和熔融盘的不同线性回归。本研究结果表明：(i) PXRF 能够可靠地识别和准确量化碳酸盐岩中 13 种常见造岩元素的浓度；(ii) 与基于泥岩的量化相比，特定于碳酸盐的量化程序为碳酸盐岩提供了更高水平的数据质量；(iii) 碳酸盐岩样品本质上是非均质的，因此需要更密集的样品制备和先进的统计方法来在量化程序中考虑到这一点；(iv) 在定量程序中必须考虑由不同样品制备引起的基质效应。(ii) 与基于泥岩的量化相比，特定于碳酸盐的量化程序为碳酸盐岩提供了更高水平的数据质量；(iii) 碳酸盐岩样品本质上是非均质的，因此需要更密集的样品制备和先进的统计方法，以在量化过程中考虑到这一点；(iv) 在定量程序中必须考虑由不同样品制备引起的基质效应。(ii) 与基于泥岩的量化相比，特定于碳酸盐的量化程序为碳酸盐岩提供了更高水平的数据质量；(iii) 碳酸盐岩样品本质上是非均质的，因此需要更密集的样品制备和先进的统计方法，以在量化过程中考虑到这一点；(iv) 在定量程序中必须考虑由不同样品制备引起的基质效应。