ELEMENTS Toolkit
Measuring Noble Gases for Thermochronology
The articles in this issue show how applications of noble gas thermochronology can help answer fundamental questions about Earth and planetary processes. Here, we discuss how noble gas measurements are actually made. We review the different methods used to extract and isolate noble gases from natural materials and to measure those gas concentrations and isotopic compositions using mass spectrometry.
Read MoreThe Art of Reactive Transport Model Building
Much like artists use their skills of abstraction, simplification, and idealization to capture the essence of a landscape, the articles in this issue of Elements on reactive transport modeling describe how theories and assumptions about the subsurface world can be translated into constructs of a mathematical world. Such theories may encompass the actions of micro- and macroorganisms, solute and gas transport, the speciation of both solid phases and surfaces, and their myriad interactions. The resulting mathematical world, built up over decades, is then distilled and interrogated numerically using computer models made up of advanced algorithms that tenaciously step through time and space.
Read MoreGEOTRACES Data Products: Standardising and Linking Ocean Trace Elements and Isotope Data at a Global Scale
GEOTRACES is an international program that involves scientists from 35 nations and that has as its primary goal an improved understanding of biogeochemical cycles and the large-scale distribution of trace elements and their isotopes (TEIs) in the ocean (www.geotraces.org). Trace elements are critical for marine life and influence the functioning of ocean ecosystems and the global carbon cycle; other trace elements are of concern as contaminants or toxins. Thus, understanding the role of trace elements in the marine environment has become a top geoscience priority.
Read MoreCompact Scanning Electron Microscopes: Impressive Analytical Tools
To expand your knowledge base, I strongly recommend reading The Role of Halogens in Terrestrial and Extraterrestrial Geochemical Processes (Springer, 2018). This remarkably comprehensive compilation of papers has been edited by Daniel E. Harlov (GFZ Potsdam, Germany) and Leonid Aranovich (IGEM RAS, Russia) and has opened my eyes to the many roles that halogens play in geochemical processes across a wide range of geologic environments. What makes this collection of papers unique is the diversity of subject matter, all focused on halogens, but with contributions from authors whose paths never likely cross at scientific meetings.
Read MoreProper Terminology in Analytical Geochemistry
Success in science has basically two components: (1) what one might call the “research component,” involving the testing of a hypothesis or the acquisition of a unique data set that provides insight into the workings of nature; (2) the “communications component”, which involves the dissemination and archiving of the knowledge that has been won. For me, the importance of this second, communications, aspect within the scientific process seems all too often underappreciated. Problems that many of us have certainly encountered in the geochemical literature range from incomplete descriptions of an analytical method, to the use of ambiguous jargon, to authors simply using the wrong terminology, etc.
Read MoreProficiency Testing: Knowing How Far You Can Trust Your Data
Proficiency testing (PT) is a cornerstone of good analytical practice, providing one of the few means of really testing the quality of a lab’s analytical output. Participation in a routine PT scheme can form part of lab accreditation, and for many industrial applications (e.g. ore grade determinations for the mining industry) it is often expected that mineral assay laboratories track their PT results. As an example, National Instrument 43-101, which is Canada’s “Standards of Disclosure for Mineral Projects”, requires the written disclosure of the methods used to verify quantitative data related to new mineral prospects seeking public funding. Hence, proficiency testing has become a de facto component of ore grade assessment whenever a mining company applies for listing on the Toronto stock exchange. Clearly, proficiency testing is not only of research importance but also plays a central role in the world’s mining industry.
Read MoreTime-of-flight Mass Spectrometry: A New Tool for Laser Ablation Analyses
I have worked in the field of mass spectrometry for some 30 years now, and I have long been interested in tracking those technical developments that might offer new options for the analytical geochemist. When laser ablation was selected as the topic for the October 2016 issue of Elements, I wanted to devote this Toolkit contribution to some emerging technology that might significantly advance mass spectrometry’s contribution to laser ablation analyses. After a bit of research, and having contacted some of the leading names in the field of laser ablation, I chose to highlight the time-of-flight (TOF) method as a new analytical strategy with promising new opportunities.
Read MoreOptical Profilometry
Understanding the fine-scale surface structure of a material can be key for many applications in the Earth sciences. For example, characterizing grain abrasion in a clastic sediment or describing the morphology of surfaces produced during a hydrothermal reaction experiment. A common approach to such imaging tasks is…
Read MoreThe New Earth and Environmental Nanoscience and Technology Centers Sponsored by NSF
Nanoscience, and the technology that stems from it (that is, nanoscience and technology), constitutes one of the great revolutions that originated in the twentieth century. Development in this field is crucial because it is central to some of the most vital issues of the twenty-first century, including safe water, mineral and energy resource development, local/regional/global contaminant issues (including disease transmission), and global climate change.
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