Instrumental technique to separate and identify molecules. Gaseous ions are formed, with or without fragmentation. Their mass/charge ratios and relative electrical abundance are then measured or the spectra are recorded.
Maps and text (Word or PDF format) and database (Excel or HTML format) for bedrock, forest floor, and mineral soil sampling in Voyageurs National Park, Minnesota to establish the background and baseline geochemistry and terrestrial mercury sources.
Report describing the results of an interdisciplinary environmental study of the World Trade Center (WTC) area after the attack on September 11, 2001. The investigations included imaging spectroscopy mapping and laboratory analysis.
Overview of chemical analyses, tracer studies, gas geochemistry, stable isotopes analyses, organic chemistry, and thermometry capabilities at major USGS laboratories with links to technique, equipment, and contacts for each procedure.
Instrument measures elemental abundance and isotopic ratios in samples as small as a few nanograms. Uses include geochronology, geological thermometry, and trace element geochemistry of geological and biological materials.