| Applications | Geochemistry, geology, paleoclimatology, hydrology, biogeochemistry: mineral sulfates/sulfides, nitrates, biogenic silicates, carbonates, apatite, soils, sediments, clays, tree rings, wood, organic materials | Sports doping (steroid abuse, testosterone origin), criminal forensics (drugs of abuse, explosives, counterfeits), archaeology (food sourcing, mummified materials), geographic origin determination | Stable isotope ecology: marine food web elucidation, animal migration tracking, agriculture crop/soil dynamics, soil mesofauna, biogeochemical processes, paleoecology | Dissolved nitrate isotope analysis (d15N, d18O) in groundwater, surface water, seawater; atmospheric greenhouse gas analysis (CO2, N2O, CH4); nitrogen cycle research; soil and organic material isotope analysis | Geochemistry, geology, climate change, hydrology, food authenticity, food adulteration, ecology, petroleum geoscience, archaeology, forensics, sports doping, environmental science, oceanography |