The SIL is equipped with two IRMS machines and each has different on-line preparation system.

  • Finnigan Delta C EA-IRMS (with TC/EA)
  • Finnigan Delta Plus GC-IRMS

The EA-IRMS systems are capable of measuring OM for both nitrogen and carbon isotopic ratios simultaneously. Additionally this system maybe modified to measure oxygen isotopic in OM, and various inorganics (sulfates, phosphates, etc.). In contrast to the EA-IRMS systems which are typically used to measure bulk materials, the GC-IRMS system is used to measure the isotopic composition of specific compounds (fatty acids, n-alkanes, etc.). Our newest on-line prep system is the Finnigan TC/EA, which will be used for thermally decomposing a variety of materials (such as cellulose, nitrates, etc.) in order to measure their oxygen isotopic composition.

Views of the lab's machines