Protocols

Comprehensive chemical analysis of water samples including major ions, trace metals, and conservative tracers using multiple analytical techniques. Includes field measurements and laboratory analyses ...

Quantitative XRD analysis of powdered rock samples using Rietveld refinement to determine mineral concentrations and spatial distribution. Samples analyzed under multiple conditions including ethylene...

High-resolution mass spectrometry analysis using Fourier Transform Ion Cyclotron Resonance to characterize the molecular composition of organic matter in different chemical extractions.

Depth-resolved sampling and analysis of subsurface materials for mineralogical composition, organic matter content, and spatial distribution of weathering products from soil through bedrock.

Extended X-ray absorption fine structure analysis of Fe-bearing colloids using synchrotron radiation with cryogenic sample preparation and shell-by-shell fitting to determine molecular coordination en...

Aqueous CO2 concentrations determined by headspace equilibration in glass bottles followed by IRGA analysis of extracted headspace gas with correction factors applied.

Separation of sediment organic carbon into free light fraction (FLF), occluded light fraction (OLF), and heavy fraction (HF) using sodium polytungstate density separation at 1.65 g/mL with sonication ...

A novel approach that captures the difference in concentration in a river segment over the difference in discharge, accounting for gains, losses or fractional solute turnover between sampling stations...

Deionized water extraction of sediments following Gregorich and Carter (2007) to measure dissolved nutrients and organic carbon. Designed to minimize physical disruption and reflect carbon and nutrien...

Applies multiple clustering algorithms (K-means, hierarchical clustering, Gaussian mixture models) to hillslope feature vectors to identify watershed zones with similar characteristics. Uses model sel...

Sequential chemical extractions using water, sodium pyrophosphate, HCl, and sodium dithionite to selectively dissolve mineral phases of varying crystallinity and their associated organic carbon.

Standard analytical chemistry methods using ion chromatography for anions and inductively coupled plasma mass spectrometry for cations and trace elements in filtered water samples.

Standardized chlorination procedure to simulate drinking water treatment and quantify the potential for organic matter to form regulated disinfection byproducts under controlled conditions.

Measurement of radiocarbon content in bulk sediments and density fractions using accelerator mass spectrometry after acid fumigation pretreatment to remove inorganic carbon.

Bayesian framework using Markov-chain Monte Carlo to infer groundwater residence time distributions from environmental tracer observations while quantifying parameter uncertainties.

Colorimetric determination of ferrous iron concentrations using ferrozine reagent with spectrophotometric measurement at 562 nm absorption peak and calibration curve from standard solutions.

Mica sheets are placed over thin sections, irradiated in a nuclear reactor, and examined under microscopy to identify areas of elevated uranium concentration through fission track density patterns. Th...

Stepped-temperature thermal analysis to quantify readily oxidizable organic carbon (OC400), total inorganic carbon (TIC), and residual organic carbon (ROC) fractions with different thermal stabilities...

Regression analysis applied to simulated water table declines across nested catchments to identify relationships between topographic characteristics, vegetation cover, and groundwater response to clim...

Correlation of daily flows with USGS stream gauge data and linear interpolation for ice-covered periods.

Dissolved sulfide concentration determined by reacting H2S with N,N-dimethyl-p-phenylene diamine under acidic conditions to form methylene blue.

Examination of collected substrates to evaluate particle loading, morphology, and spatial distribution.

Sample pre-treatment method using PPL cartridges (Bond Elut) after acidifying samples to pH 2 with phosphoric acid to extract organic compounds.

Measurement of hydrogen and oxygen isotope ratios using Off-Axis Integrated Cavity Output Spectrometer with auto-sampler and heated injector block. Results reported in δ-notation relative to Vienna St...

Regional assessments of major aquifer systems providing quantitative assessments of water occurrence, movement, and availability. Includes classification of stratigraphic sequences and generation of m...

Laboratory analysis to determine total dissolved solids concentration in water samples through evaporation technique.