Preprints
Filtering by Subject: Inorganic Chemistry
Quantifying sulfur speciation in magmatic-hydrothermal fluids
Published: 2025-06-11
Subjects: Chemistry, Earth Sciences, Geochemistry, Geology, Inorganic Chemistry, Natural Resource Economics, Physical Chemistry, Physical Sciences and Mathematics
Quantitative knowledge of sulfur speciation in the fluid phase is key to understanding sulfur degassing from magmas and its transfer along with metals by fluids across the lithosphere. Farsang and Zajacz(1) recently reported new sulfur speciation data using Raman spectroscopy measurements on aqueous H2SO4-NaCl(-KCl) solutions trapped as synthetic fluid inclusions in quartz at 875 °C and 2 kbar [...]
Prioritizing Safety, Advancing Efficiency: Developing a New Total Phosphorous Microwave Digestion Method for Sediment Core Nutrient Analysis
Published: 2024-09-26
Subjects: Biogeochemistry, Environmental Chemistry, Inorganic Chemistry, Soil Science
Long-term datasets are invaluable resources for understanding broad-level temporal patterns in ecosystems. For over two decades, UC Davis and Lake County Water Resources Department have collaborated on a long-term monitoring project of Clear Lake sediment nutrient concentrations, in an effort to better understand nutrient cycling in Clear Lake. When the need for a new total phosphorus digestion [...]
Isotopic composition (238U/235U) of some commonly used uranium reference materials
Published: 2017-11-05
Subjects: Chemistry, Cosmochemistry, Earth Sciences, Geochemistry, Inorganic Chemistry, Physical Sciences and Mathematics
We have determined 238U/235U ratios for a suite of commonly used natural (CRM 112a, SRM 950a, and HU-1) and synthetic (IRMM 184 and CRM U500) uranium reference materials by thermal ionisation mass-spectrometry (TIMS) using the IRMM 3636 233U–236U double spike to accurately correct for mass fractionation. Total uncertainty on the 238U/235U determinations is estimated to be <0.02% (2σ). These [...]
238U/235U Systematics in Terrestrial Uranium-Bearing Minerals
Published: 2017-11-05
Subjects: Chemistry, Cosmochemistry, Earth Sciences, Geochemistry, Inorganic Chemistry, Physical Sciences and Mathematics
The present-day 238U/235U ratio has fundamental implications for uranium-lead geochronology and cosmochronology. A value of 137.88 has previously been considered invariant and has been used without uncertainty to calculate terrestrial mineral ages. We report high-precision 238U/235U measurements for a suite of uranium-bearing minerals from 58 samples representing a diverse range of lithologies. [...]