Description of a new Micro-XRay spectrometer

Haschke, Michael; Scholz, W.; Theis, Ulrich; Nicolosi, Joe; Scruggs, B.; Herzceg, L.

doi:10.1051/jp4:20020216

Cited by 15 publications

(11 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A parallel development was the Eagle II and III BKA XRF core scanners, built by Röntgenanalytik Messtechnik GmbH, Germany (Haschke et al 2002;Hascke 2006). These instruments, developed from the Eagle μprobe, had several innovations including use of capillary optics to focus the incident X-ray beam allowing very high spatial resolution, down to 30 µm spot size and 10 µm step size.…”

Section: The Development Of Xrf Core Scannersmentioning

confidence: 99%

Twenty Years of XRF Core Scanning Marine Sediments: What Do Geochemical Proxies Tell Us?

Rothwell

Croudace

2015

Developments in Paleoenvironmental Research

138

128

View full text Add to dashboard Cite

XRF core scanners, with their rapid and non-destructive analytical capability, have now been used for two decades in the analysis of marine sediments. Initially they were used to record variations in fundamental parameters such as calcium carbonate stratigraphy and terrigenous sediment delivery, using major element integrals, such as Ca and Fe, to provide detailed insights into oceanographic and climatic processes. In recent years, proxy selection has progressed to routine normalisation and presentation as log-ratios to include 60 elements or ratios to document a wide range of environmental and process changes. We review the development and application of XRF core scanning of marine sediments and discuss the basis of particular proxies, their uses and limitations to assist users in their selection. To date, there has been no systematic overview of elemental proxies and their application in the analysis of marine sediment records.

show abstract

Section: The Development Of Xrf Core Scannersmentioning

confidence: 99%

Twenty Years of XRF Core Scanning Marine Sediments: What Do Geochemical Proxies Tell Us?

Rothwell

Croudace

2015

Developments in Paleoenvironmental Research

138

128

View full text Add to dashboard Cite

show abstract

“…Although the AVAATECH and ITRAX core scanners are the main instruments in current use, the EAGLE III micro-XRF scanner (developed by Röntgenanalytik Messtechnik GmbH, Germany, and described by Haschke et al 2002, andHaschke 2006) is an effective tool for high-resolution study of geochemical variability of small sub-samples (up to 15 × 15 cm). In contrast to the AVAATECH and ITRAX instruments, the EAGLE III holds the sample within a large vacuum-tight chamber to improve light element detection and uses a polycapillary lens to focus a small circular X-ray spot onto the sample surface.…”

Section: Lacustrine Fluvial and Terrestrial Applicationsmentioning

confidence: 99%

Micro-XRF Studies of Sediment Cores: A Perspective on Capability and Application in the Environmental Sciences

Rothwell

Croudace

2015

Micro-XRF Studies of Sediment Cores

View full text Add to dashboard Cite

XRF core scanners represent a major innovation in the analysis of cored sediment sequences and have revolutionised palaeoenvironmental research over the last decade. Such scanners provide capability to rapidly and non-destructively record element proxy variations at decadal, annual and even sub-annual scales. Their use, initially by the marine science community, was soon taken up by lake core researchers, particularly after the advent of high-resolution models incorporating x-radiography, particularly suited for analysis of varved sequences. Their impact on the environmental sciences is seen in the exponential rise in research papers published since 2005 involving their use. Although their main application has been in the study of Quaternary marine and lake cores, they have also been used in the analysis of terrestrial hard rock cores in mining applications, analysis of loess cores, speleothems, cores from peat bogs and river banks and cores collected for environmental forensics and pollution studies. Further, an important cohort of papers has addressed interpretation and calibration issues, increasing the robustness of acquired datasets. In this paper we review marine and lacustrine applications of XRF core scanning, together with environmental forensics applications and research into data optimisation and calibration presented in the current volume. We provide synopses of the principal findings and a concise summary of the current work.

show abstract

“…Progress in XRF instrumentation has opened the way to on-line measurement of (soft) sediment cores aboard ship by means of XRF-core-scanning devices (Jansen et al 1998;Wien et al 2005;Ge et al 2005;Rothwell and Rack 2006). Technical descriptions of the various XRF core scanners in current use are given by Jansen et al (1998), Croudace et al (2006), Haschke et al (2002), Haschke (2006), and Richter et al (2006) and summarised in this volume by Jarvis et al The major advantage of XRF core scanning over conventional geochemical analysis of discrete specimens is that element intensities are obtained directly at the surface of a split sediment core, which implies up to two orders of magnitude increase in analytical speed. In addition, the spatial resolution of XRF core-scanning devices is much higher than that of conventional destructive methods, and allows the extraction of near-continuous records of element intensities from sediment cores.…”

Section: Introductionmentioning

confidence: 99%

Prediction of Geochemical Composition from XRF Core Scanner Data: A New Multivariate Approach Including Automatic Selection of Calibration Samples and Quantification of Uncertainties

Weltje

Bloemsma

Tjallingii

et al. 2015

Developments in Paleoenvironmental Research

145

175

View full text Add to dashboard Cite

A multivariate log-ratio calibration (MLC) model for XRF-core-scanning devices is presented, based on a combination of basic XRF-spectrometry theory and principles of compositional data analysis. The performance of the MLC model is evaluated in comparison with other empirical calibration procedures for XRF core scanner data using two data sets acquired with two different XRF core scanners. The quality of calibration models is assessed by calculating the uncertainties associated with predicted concentrations using cross-validation techniques. Results show that (1) the commonly used direct linear calibration (DLC) methods, which are based on the questionable assumption of a unique linear relation between intensities and concentrations and do not acknowledge the compositional nature of the calibration problem, give poor results; (2) the univariate log-ratio calibration (ULC) model, which is consistent with the compositional nature of the calibration problem but does not fully incorporate absorption and enhancement effects on intensities, and permits estimation of "relative" concentrations only, is markedly better, and (3) the MLC algorithm introduced in this contribution, which incorporates measurement uncertainties, accommodates absorption and enhancement effects on intensities, and exploits the covariance between and among intensities and concentrations, is the best by far. The predictive power of the MLC model may be further increased by employing automatic sample selection based on the multivariate geometry of intensity measurements in log-ratio space. The precision attained by MLC in conjunction with automatic sample selection is comparable to that attained by conventional XRF analysis of heterogenous materials under laboratory conditions. A solution to the long-standing problem of XRF core scanner calibration implies that high-resolution records of sediment composition with associated uncertainties can now be routinely established, which should increase the range of quantitative applications of XRF-core-scanning devices and strengthen inferences based on analysis of geochemical proxies.

show abstract

Description of a new Micro-XRay spectrometer

Cited by 15 publications

References 0 publications

Twenty Years of XRF Core Scanning Marine Sediments: What Do Geochemical Proxies Tell Us?

Twenty Years of XRF Core Scanning Marine Sediments: What Do Geochemical Proxies Tell Us?

Micro-XRF Studies of Sediment Cores: A Perspective on Capability and Application in the Environmental Sciences

Prediction of Geochemical Composition from XRF Core Scanner Data: A New Multivariate Approach Including Automatic Selection of Calibration Samples and Quantification of Uncertainties

Contact Info

Product

Resources

About