Metamorphic Effects on Nitrogen Isotopes in Sedimentary Rock
Studying nitrogen isotopes in sedimentary rocks has become an important tool for investigating past environmental conditions. Nitrogen can be found in sedimentary rocks bound to kerogen or substituted in potassic minerals. When studying nitrogen isotopes, researchers usually focus on kerogen extracts alone, or they focus on bulk rocks that include both phases of nitrogen. Questions remain over which sample type more accurately reflects the original composition of biomass from which the nitrogen was derived. Recent research examines how nitrogen is altered as its stored in these two phases, and which sampling method provides the best results when studying the primary isotopic composition of biomass in different rock types.
The paper, “Differential metamorphic effects on nitrogen isotopes in kerogen extracts and bulk rocks,” was published in the journal Geochimica et Cosmochimica Acta. The work was supported by NASA Astrobiology through the Exobiology & Evolutionary Biology Program.