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QEMSCAN

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QEMSCAN
InventorCSIRO
Inception2001
ManufacturerFEI Company
Availableyes
Current supplierFEI Australia Center of Excellence for Natural Resources
Last production year2013
Websitehttp://www.fei.com/applications/industry

QEMSCANis the name for an integratedautomated mineralogy and petrographysystem providing quantitative analysis ofminerals,rocksand man-made materials. QEMSCAN is an abbreviation standing forquantitative evaluation of minerals by scanning electron microscopy,and aregistered trademarkowned byFEI Companysince 2009. Prior to 2009, QEMSCAN was sold by LEO, a company jointly owned by Leica and ZEISS. The integrated system comprises ascanning electron microscope(SEM) with a large specimen chamber, up to four light-elementenergy-dispersive X-ray spectroscopy(EDS) detectors, andproprietary softwarecontrolling automated data acquisition. The offline software package iDiscover provides data processing and reporting functionality.

Mineral identification and quantification[edit]

QEMSCAN image of a fluvial sandstone, grid size=500 μm

QEMSCAN creates phase assemblage maps of a specimen surface scanned by a high-energy accelerated electron beam along a predefinedraster scanpattern. Low-countenergy-dispersive X-ray spectra(EDX) are generated and provide information on the elemental composition at each measurement point. The elemental composition in combination with back-scattered electron (BSE) brightness and x-ray count rate information is converted into mineral phases.[1]QEMSCAN data includes bulk mineralogy and calculated chemical assays. By mapping the sample surface, textural properties and contextual information such as particle and mineralgrain sizeand shape, mineral associations, mineral liberation, elemental deportment,porosity,and matrixdensitycan be calculated, visualized, and reported numerically. Data processing capabilities include combining multiple phases into mineral groups, resolving mixed spectra (boundary phase processing), image-based filtering, and particle-based classification. Quantitative reports can be generated for any selected number of samples, individual particles, and for particle classes sharing similar compositional and/or textural attributes, such as size fractions or rock types.

Sample types and preparation[edit]

QEMSCAN is routinely employed in the analysis of rock- and ore-forming minerals. Sample preparation requirements include a level, dry specimen surface, coated with a thin electrically conductive layer (e.g. carbon). The sample must be stable underhigh vacuumconditions and the electron beam, typically 15 to 25 kV. Common sample types include 30 mm resin-impregnated blocks ofdrill cuttingsandore,thin sectionsofdrill coreandrocks,as well assoilsamples. Very small particles such as atmosphericdusthave been measured on carbon tape or filter paper.Coalsamples are generally mounted incarnauba wax,providing sufficient contrast to allow for separation of the sample from the mounting medium, and subsequent measurement of coal andmacerals.

Software suite[edit]

QEMSCAN consists of proprietary software packageiDiscoverwhich consists of four software modules:

  1. Datastore Explorer- data management module
  2. iMeasure- measurement module, SEM and EDS control
  3. iExplorer- data processing and classification tools, mineral database management, reports
  4. SIP editor- phase identification protocol

Measurement modes[edit]

QEMSCAN consists of five customisable measurement modes:

  1. BMAbulk mineralogical analysis
  2. PMAparticle mineralogical analysis
  3. SMSspecific mineral search
  4. TMStrace mineral search
  5. Field Imagesurface imaging mode

Applications[edit]

QEMSCAN measurements can be applied in quantitative mineral characterisation ofrocks,weatheringproducts such asregolithandsoils,and most man-made materials. As a result, it has commercial and scientific applications inminingandmineral processing;[2]O&G;[3]coal;[4]environmental sciences;,[5][6]forensic geosciences;[7]archaeology;[8]agribusiness;built environmentandplanetary geology.[9]

History[edit]

  • 1970sCSIROAustralia devised a way to automatically useEnergy-dispersive X-ray spectroscopytechnology and ascanning electron microscopeto accurately image and identify minerals in ore samples.[10]This technology became patented and known as QEM*SEM (quantitative evaluation of minerals by scanning electron microscopy)
  • 1980sNewdigitalhardware andsoftwaredevelopments byCSIROallowed for automated analysis of multiple samples, creation of particle images form which mineralogy, texture and metallurgical parameters can be extracted and quantified.
  • 1990sLight elementX-ray detectorsare introduced improving the mineral identification. TheJulius Kruttschnitt Mineral Research Centreat theUniversity of Queenslanddevelops the Mineral Liberation Analyzer (MLA) expert software.
  • 2001CSIROannounces intention to commercialise QEMSCAN.
  • 2003Intellection Pty Ltd. is founded to develop, market and sell QEMSCAN technology solutions[buzzword]based on the ZEISS EVO scanning electron microscope.
  • 2009FEI Companyannounces the acquisition of selected assets from Intellection Pty Ltd., including the QEMSCAN technology.
  • 2010, June.Ammtec completes the first "on site" analysis, utilising an "R" series QEMSCAN, at an oil well drilling site in Sumatra, RI.[1]
  • Sep.1, 2010press releaseon version 5.0 iDiscover software including a new spectral analysis system capable of identifying 72 elements for improved complex mineral composition discrimination.
  • Nov.15, 2010press releaseon new website launch for QEMSCAN andMLAAutomated Mineralogysolutions[buzzword]forNatural Resources
  • Oct. 19, 2011press releaseon introduction of QEMSCAN WellSite analysis solution[buzzword],field-tested on onshore and offshore oil platforms in collaboration with mudlogging service providers and oil & gas companies, includingHalliburton,Oil Search LimitedandMaersk.
  • 2015Development of QEMSCAN ceases.

References[edit]

  1. ^Gottlieb, P., Wilkie, G., Sutherland, D., Ho-Tun, E., Suthers, S., Perera, K., Jenkins, B., Spencer, S., Butcher, A., Rayner, J. 2000. Using quantitative electron microscopy for process mineralogy applications.JOM - Journal of the Minerals, Metals and Materials Society,52,4, 24-25.doi:10.1007/s11837-000-0126-9
  2. ^Goodall, W.R., Scales, P.J., Butcher, A.R. 2005. The use of QEMSCAN and diagnostic leaching in the characterisation of visible gold in complex ores.Minerals Engineering,18,8, 877-886 doi:10.1016/j.mineng.2005.01.018
  3. ^Fröhlich, S., Redfern, J., Petitpierre, L., J.D. Marshall, M. Power, Grech, P. 2010. Diagenetic evolution of incised channel sandstones: implications for reservoir characterisation of the Lower Carboniferous Marar Formation, Ghadames Basin, Western Libya.Journal of Petroleum Geology,33;3-18.abstract
  4. ^Liu, Y., Gupta, R., Sharma, A., Wall, T., Butcher, A., Miller, G., Gottlieb, P., French, D. 2005. Mineral matter–organic matter association characterisation by QEMSCAN and applications in coal utilisation.Fuel,84,10, 1259–1267.doi:10.1016/j.fuel.2004.07.015
  5. ^Haberlah, D., Williams, M.A.J., Halverson, G., Hrstka, T., Butcher, A.R., McTainsh, G.H., Hill, S.M., Glasby, P. 2010. Loess and floods: high-resolution multi-proxy data of Last Glacial Maximum (LGM) slackwater deposition in the Flinders Ranges, semi-arid South Australia.Quaternary Science Reviews,29,19-20, 2673–2693.doi:10.1016/j.quascirev.2010.04.014
  6. ^Haberlah, D., Strong, C., Pirrie, D., Rollinson, G.K., Gottlieb, P., Botha, W.S.K., Butcher, A.R. 2011. Automated petrography applications in Quaternary Science.Quaternary Australasia,28(2),3–12
  7. ^Pirrie, D., Power, M.R., Rollinson, G.K., Wiltshire, P.E.J., Newberry, J., Campbell, H.E. 2005. Automated SEM-EDS (QEMSCAN) Mineral Analysis in Forensic Soil Investigations: Testing Instrumental Reproducibility. In:K. Ritz et al. (eds.) Criminal and Environmental Soil Forensics,84,10, 411-430, Springer Science doi:10.1007/978-1-4020-9204-6_26
  8. ^Knappett, C., Pirrie, D., Power, M.R., Nikolakopoulou, I., Hilditch, J., Rollinson, G.K. 2005. Mineralogical analysis and provenancing of ancient ceramics using automated SEM-EDS analysis (QEMSCAN): A pilot study on LB I pottery from Akrotiri, Thera.Journal of Archaeological Science,in pressdoi:10.1016/j.jas.2010.08.022
  9. ^Schrader, C.M., Rickman, D., Stoeser, D., Wentworth, S.J., Botha, P.W.S.K., Butcher, A.R., McKay, D., Horsch, H., Benedictus, A., Gottlieb, P. 2008. Analysis of Lunar Highland Regolith Samples from Apollo 16 Drive Core 64001/2 and Lunar Regolith Simulants - An Expanding Comparative Database.NASA Technical Report,MSFC-2144abstract
  10. ^Frost, M. T., O'Hara, K., Suddaby, P., Grant, G., Reid, A.F., Wilson, A.F., Zuiderwyk, M. 1977. A description of two automated control systems for the electron microprobe.X-Ray Spectrometry,5,4, 180-187.doi:10.1002/xrs.1300050403

External links[edit]

  • Automated Mineralogy Resources- Online repository for journal papers, conference abstracts, published reports and theses on SEM-EDS based automated mineralogy and petrography applications
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