The tangled tale of Kīlauea’s 2018 eruption as told by geochemical monitoring

Science ◽  
2019 ◽  
Vol 366 (6470) ◽  
pp. eaaz0147 ◽  
Author(s):  
Cheryl Gansecki ◽  
R. Lopaka Lee ◽  
Thomas Shea ◽  
Steven P. Lundblad ◽  
Ken Hon ◽  
...  

Changes in magma chemistry that affect eruptive behavior occur during many volcanic eruptions, but typical analytical techniques are too slow to contribute to hazard monitoring. We used rapid energy-dispersive x-ray fluorescence analysis to measure diagnostic elements in lava samples within a few hours of collection during the 2018 Kīlauea eruption. The geochemical data provided important information for field crews and civil authorities in advance of changing hazards during the eruption. The appearance of hotter magma was recognized several days before the onset of voluminous eruptions of fast-moving flows that destroyed hundreds of homes. We identified, in near real-time, interactions between older, colder, stored magma—including the unexpected eruption of andesite—and hotter magma delivered during dike emplacement.

1979 ◽  
Vol 23 ◽  
pp. 163-176
Author(s):  
D. C. Camp ◽  
W. D. Ruhter

In the event that nuclear fuel from light water reactors (LWR) is reprocessed to reclaim the uranium or plutonium, several analytical techniques will be used for product accountability. Generally, the isotopic content of both the plutonium and uranium in the reprocessed product will have to be accurately determined. One plan for the reprocessing of LWR spent fuel incorporates the following scheme. After separation from both the fission products and transplutonium actinides (including neptunium and americium), part of the uranium and all of the plutonium in a nitrate solution will merge together to form a coprocessed stream. This solution will be concentrated by evaporation and sent to a hold tank for accountability. Input concentrations into the hold tank could be up to 350 g U/ℓ and nearly 50 g Pu/ℓ. The variation to be expected in these concentrations is not known. The remaining uranium fraction will be further purified and sent to a separate storage tank. Its expected stream concentration will be about 60 g U/ℓ. These two relatively high actinide stream concentrations can be monitored rapidly, quantitatively, and nondestructively using the technique of energy-dispersive x-ray fluorescence analysis(XRFA).


1983 ◽  
Vol 19 (2) ◽  
pp. 201-211 ◽  
Author(s):  
A. B. Cormie ◽  
D. E. Nelson

AbstractThe use of energy-dispersive X-ray fluorescence analysis (XES) for the routine identification of three tephras (Mazama, Bridge River, Mount St. Helens Yn) commonly found in archeological sites in British Columbia has been investigated. Researchers have often assumed that chemical analysis of bulk samples of glass separates would be hampered by contamination and weathering effects. Our results indicate that XES of bulk glass separates provides a very reliable method for rapidly identifying the three tephras in question, even with a very simple sample preparation. This should enable persons not skilled in geology or in tephrochronology to collect and to identify samples of these tephras. Finally, as a part of the study, similar measurements were made on the separated glass portions of these three tephras and of three others (Glacier Peak B and G, White River) from northwest North America. The results suggest that this method may provide tephrochronologists with a useful additional tool for studying tephras in other regions.


Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 426
Author(s):  
Behrooz Abbasi ◽  
Xiaoliang Wang ◽  
Judith C. Chow ◽  
John G. Watson ◽  
Bijan Peik ◽  
...  

Respirable coal mine dust (RCMD) exposure is associated with black lung and silicosis diseases in underground miners. Although only RCMD mass and silica concentrations are regulated, it is possible that particle size, surface area, and other chemical constituents also contribute to its adverse health effects. This review summarizes measurement technologies for RCMD mass concentrations, morphology, size distributions, and chemical compositions, with examples from published efforts where these methods have been applied. Some state-of-the-art technologies presented in this paper have not been certified as intrinsically safe, and caution should be exerted for their use in explosive environments. RCMD mass concentrations are most often obtained by filter sampling followed by gravimetric analysis, but recent requirements for real-time monitoring by continuous personal dust monitors (CPDM) enable quicker exposure risk assessments. Emerging low-cost photometers provide an opportunity for a wider deployment of real-time exposure assessment. Particle size distributions can be determined by microscopy, cascade impactors, aerodynamic spectrometers, optical particle counters, and electrical mobility analyzers, each with unique advantages and limitations. Different filter media are required to collect integrated samples over working shifts for comprehensive chemical analysis. Teflon membrane filters are used for mass by gravimetry, elements by energy dispersive X-ray fluorescence, rare-earth elements by inductively coupled plasma-mass spectrometry and mineralogy by X-ray diffraction. Quartz fiber filters are analyzed for organic, elemental, and brown carbon by thermal/optical methods and non-polar organics by thermal desorption-gas chromatography-mass spectrometry. Polycarbonate-membrane filters are analyzed for morphology and elements by scanning electron microscopy (SEM) with energy dispersive X-ray, and quartz content by Fourier-transform infrared spectroscopy and Raman spectroscopy.


1983 ◽  
Vol 12 (4) ◽  
pp. 175-181 ◽  
Author(s):  
P. Hoffmann ◽  
K. H. Lieser ◽  
T. Hofmann ◽  
R. Sommer

2010 ◽  
Vol 68 (4-5) ◽  
pp. 525-528 ◽  
Author(s):  
R. Cesareo ◽  
C. Calza ◽  
M. Dos Anjos ◽  
R.T. Lopes ◽  
A. Bustamante ◽  
...  

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