Skip to Content

Electron Microprobe Laboratory (Cameca sx-100)

The electron microprobe is used to analyze the composition of meteorites, Lunar rocks and terrestrial samples. The electron microprobe sends an electron beam in situ on a flat cm-size thin slab of rock to analyze a small spot of less than 1 micrometer size. It uses the generated X-rays to provide a quantitative analysis of the major and minor chemical elements of minerals and glasses composing the sample. The electron microprobe can also produce maps of the elements showing their distribution in the sample.

Purpose: quantitative chemical analyses of major elements in solids

  • Spot analyzes < 1 micrometer
  • Element maps
  • Material analyzed:
    • Meteorites: from primitive solar nebula materials to more evolved asteroid chunks
    • Mars rocks (meteorites)
    • Moon rocks (meteorites, & Apollo rocks & soils)
    • Earth rocks
    • Experimentally made or altered rocks
      • High temperature and pressure samples simulating planetary interiors
      • Impacted samples simulating planetary collisions
      • Exobiology: samples altered in the lab simulating erosion and alteration
      • Moon and Mars simulants


  • Manufacturer: Cameca
  • Type: SX100
  • 5 wavelength dispersive spectrometers (WDS)
  • 1 Energy Dispersive Spectrometer (EDS) by iXRF
  • Tungstene filament
  • Automated stage down to < 3 micrometer precision
  • Analysis down to several 100 ppm weight for selected elements
  • Analysis of Boron to Bismuth
  • Sample should be flat, polished and, carbon coated
  • Large variety of natural and synthetic standards

Labs & research programs supported

  • Meteorite curation: identification of new meteorites
  • Lunar rock & soil curation
  • Exobiology research
  • Isotope geochemistry
  • Experimental petrology
    • Gas mixing high temperature lab
    • High-pressure and high-temperature lab
    • Impact lab (this is not a Petrology lab)
  • Primitive materials (early solar system research)
  • Mars research
  • Lunar research
  • Meteorite research

Lab Leads
Lindsay Keller (281-483-6090), NASA
Anne Peslier (281-244-6714), Jacobs JETS
Electron Microprobe Lab Instruments
Electron Microprobe Lab Instruments