Evaluating formation fluid models and calibrations using clumped isotope paleothermometry on Bahamian dolomites

Estimating Cambro-Ordovician seawater temperature and isotopic composition using carbonate clumped isotope paleothermometry on calcitic and phosphatic fossils

Antarctic ice growth before and after the Eocene-Oligocene transition: New estimates from clumped isotope paleothermometry

Across the Eocene-Oligocene transition, the oxygen isotopic composition (δO) of benthic and planktonic foraminifera increased by over 1‰. This shift is thought to represent a combination of global cooling and the growth of a large ice sheet on the Antarctic continent. To determine the contribution of each of these factors to the total change in δO, we measured the clumped isotopic composition o...

Statistical clumped isotope signatures

High precision measurements of molecules containing more than one heavy isotope may provide novel constraints on element cycles in nature. These so-called clumped isotope signatures are reported relative to the random (stochastic) distribution of heavy isotopes over all available isotopocules of a molecule, which is the conventional reference. When multiple indistinguishable atoms of the same e...

Methane seep carbonates yield clumped isotope signatures out of equilibrium with formation temperatures

Methane cold seep systems typically exhibit extensive buildups of authigenic carbonate minerals, resulting from local increases in alkalinity driven by methane oxidation. Here, we demonstrate that modern seep authigenic carbonates exhibit anomalously low clumped isotope values (Δ47), as much as ∼0.2‰ lower than expected values. In modern seeps, this range of disequilibrium translates into appar...

Physiological impacts on alkenone paleothermometry

[1] We conducted isothermal (15 C) batch culture experiments with the coccolithophorid Emiliania huxleyi (strain NEPCC 55a) to evaluate the extent to which nutrient and light stress contribute to variability in the alkenone unsaturation index U37 K0. Alkenone content and composition were constant throughout exponential growth in both experiments when nutrients (nitrate and orthophosphate) were ...