A portable x-ray fluorescence (XRF) spectrometer and mobile test stand have been employed to examine the feasibility of on site measurements of trace metals in estuarine sediment. In the laboratory, the instrument was able to detect the trace metals: As, Cr, Cu, Pb, Sn and Zn; and the geochemical proxy metals: Ca, Fe, K and Rb; in both fresh and freeze-dried surficial samples from the Tamar and Tavy estuaries, southwest England, that had been emplaced in polyethylene bags over the detector window. The presence of interstitial water in fresh samples acted as both a diluent of sediment mass and an attenuator of incident and fluorescent x-rays, resulting in measured (fresh weight) metal concentrations that were significantly lower than corresponding (dry weight) concentrations derived from dry analyses. Gravimetric correction for fractional water content (f_w ~ 0.2–0.6) gave rise to results that were within 20% of those derived from dry analyses with the exception of K, whose relatively low energy fluorescent x-rays were subject to significant attenuation from the aqueous medium; further x-ray attenuation was observed for both K and Ca through the sample bag, thereby limiting the usefulness of the approach for these metals. A relationship between the concentration of Rb and f_w in fresh samples suggests that Rb may be used as a proxy for interstitial water content through its covariance with sediment grain size. Accordingly, on site measurements of trace metals of sufficient fluorescent x-ray energies may be corrected empirically with respect to Rb in order to simultaneously account for variations in granulometry and mass contribution of water. On this basis, results from an axial transect of the Tamar and an intertidal transect in the Tavy were able to detect variations in trace metal concentrations that were consistent with known sources and geochemical behaviours.

便携式X射线荧光（XRF）光谱仪和移动测试台已被用来检验在河口沉积物中痕量金属进行现场测量的可行性。在实验室中，该仪器能够检测到痕量金属：As，Cr，Cu，Pb，Sn和Zn； Al，Cr和Cu。以及地球化学替代金属：Ca，Fe，K和Rb；取自英格兰西南部Tamar和Tavy河口的新鲜和冻干表面样品，这些样品已放置在探测器窗口上方的聚乙烯袋中。新鲜样品中存在的间隙水既充当沉积物质量的稀释剂，又充当入射和荧光X射线的衰减剂，导致测得的（新鲜重量）金属浓度明显低于源自干燥的相应（干燥重量）浓度。分析。˚F_瓦特〜0.2-0.6）产生了作为这些从干分析衍生的具有K之外，其相对低的能量的荧光X射线是受到来自水性介质显著衰减的20％之内的结果; 通过样品袋还观察到了K和Ca的进一步X射线衰减，从而限制了该方法对这些金属的实用性。Rb的浓度与f _w的关系新鲜样品中的Rb表明，Rb可以通过其与沉积物粒径的协方差来代替间隙水含量。因此，可以相对于Rb凭经验校正具有足够的荧光x射线能量的痕量金属的现场测量，以便同时考虑粒度的变化和水的质量贡献。在此基础上，塔玛的轴向横断面和泰维河的潮间横断面的结果能够检测出痕量金属浓度的变化，这些变化与已知来源和地球化学行为一致。