Aromatic biomarker extractions via GC-MS from a sequence of Eocene clay-sands showing differences in the source of organic matter to the sediments (different organics come out in different samples)
You can learn a lot from some rocks
Lipid biomarkers and light stable isotopes (C, N, S, H) are great tools to decipher what physical and biologic factors influenced the development of ancient ecosystems. I use these tools to define and quantify perturbations within past environments. For example, mapping distributions of polycyclic alkanes and carotenoids to climactically driven sedimentary sequences to determine changes in relative salinity, alkalinity, and aridity. Alternatively, exploring variations within locally produced marine organic matter export and pulses of transported terrigenous kerogen (plant and soil organic matter) to look at carbon sequestration in polar basins. Understanding ancient ecosystem response to external stresses can help us better predict what may happen to our present ecosystems moving forward.
Some things lipids and isotopes can teach you:
pH effects on redox processes in Jurrasic rift lakes: https://doi.org/10.1016/j.gca.2019.03.014
Silicified biomarkers: https://doi.org/10.1111/gbi.12620
Bits of the water fern, Azolla, before being ground up as a modern analog
Some Silurian iron-rich strata in the Appalachians, PA
Chemostratigraphy throughout the Lower Jurrasic Towaco Fm., Newark Basin. Differences in basin regime type (deepening, stratified, shallowing/arid) are shown in different colors and are reflected in the organic isotope and lipid biomarker proxies.
Fossil-y iron-y rocks!
Silurian-age rocks collected throughout the Appalachians