Regionally Correlated Oxygen and Carbon Isotope Zonation in Diagenetic Carbonates of the Bakken Formation

Dolomite reference material synthesized by pressureless sintering for laser ablation MC-ICP-MS carbon and magnesium isotope analysis

“…[8][9][10] Micron-scale spatial resolution measurements of C and Mg isotope ratios in dolomite provide a powerful perspective for the detailed characterization of these geological processes. 11 Laser ablation multi-collector inductively coupled plasmamass spectrometry (LA-MC-ICP-MS) is popularly adopted for precise and accurate in situ C and Mg isotopic analyses, commonly with the prerequisite of calibration against a matrixmatched standard to correct the matrix-induced isotopic fractionation. [12][13][14][15][16][17][18][19] Since the MgO content varies from ∼22 wt% to 5 wt% of natural dolomites, 20,21 it is a challenge to establish a series of matrix-matched dolomite standards.…”

“…8–10 Micron-scale spatial resolution measurements of C and Mg isotope ratios in dolomite provide a powerful perspective for the detailed characterization of these geological processes. 11…”

High Spatial-resolution Assessment of Diagenesis and Primary Isotopic Variability in Maastrichtian Molluscan Carbonates from Antarctica

“…Recent developments in secondary ion mass spectrometry (SIMS) of carbonates allows for the precise measurement of much smaller ng-scale domains (~10 µm diameter x 1 µm deep pits, Valley & Kita, 2009), which can assist attempts to disentangle the effects of diagenesis and time averaging (e.g. Denny et al, 2020;Linzmeier et al, 2016).…”

“…These carbonate materials grow within the finite lifespans of individual organisms and record ambient conditions when shell precipitation occurs. Subsequent processesincluding dissolution and reprecipitation, recrystallization, and precipitation of secondary domains of carbonatecan alter the original carbonate material and therefore the interpretation of the geochemical proxy (Immenhauser et al, 2016). Commonly, bulk proxy measurements integrate volumes of material ( >10 µg or ~0.004 mm 3 ) that not only might represent a considerable length of time during the growth of the organism but may also include altered domains.…”