Environchron
Analytical Services
Rigorous, method-validated analyses for environmental research and regulatory compliance.
Radioisotope Analysis & Radiometric Dating
Short-lived radioisotopes are the foundation of sediment chronology, providing the temporal framework needed to interpret environmental change. Environchron employs gamma spectrometry to measure Pb-210, Cs-137, Th-234, Ra-226, and Ra-228 with high precision, enabling age-depth models that span the last 100–150 years.
Applications
- —Pb-210 dating via gamma spectrometry (CRS, CIC, CFCS models)
- —Cs-137 gamma spectrometry — 1963 weapons testing and 1986 Chernobyl markers
- —Ra-226 supported background determination
- —Ra-228 submarine groundwater discharge and water mass tracing
- —Sedimentation rate and accumulation history reconstruction
Method Specifications
| Pb-210 Method | Gamma spectrometry (HPGe detector) |
| Cs-137 Method | Gamma spectrometry (HPGe detector) |
| Pb-210 Detection Limit | < 0.5 dpm/g dry weight |
| Cs-137 Detection Limit | < 0.2 dpm/g dry weight |
| Chronological Range | ~0–150 years BP |
Geochemical Analysis
Comprehensive geochemical characterization of sediment cores provides depth-resolved records of elemental composition, mineralogy, and organic matter dynamics. Environchron integrates XRF elemental profiling, XRD mineralogy, stable isotope analysis, pigment analysis, and total organic carbon measurements to reconstruct environmental and depositional histories.
Applications
- —Elemental characterization by X-ray fluorescence (XRF) — major and trace elements
- —Mineralogy by X-ray diffraction (XRD)
- —Stable carbon and nitrogen isotopes (δ¹³C, δ¹⁵N) by EA-IRMS
- —Chlorophyll and phaeophytin pigment analysis
- —Total organic carbon (TOC) determination
- —Contaminant chronology and source attribution
- —Nutrient loading and eutrophication history
Method Specifications
| XRF Method | Energy-dispersive or wavelength-dispersive XRF |
| XRD Method | Powder X-ray diffraction |
| Stable Isotopes | EA-IRMS; δ¹³C ± 0.1‰, δ¹⁵N ± 0.2‰ |
| Pigments | Spectrophotometric analysis (chlorophyll a, phaeophytin) |
| TOC | Loss-on-ignition or elemental analyzer |
Sedimentology
Physical sediment characterization provides the stratigraphic and compositional context essential for interpreting geochemical and biological proxies. Environchron measures grain size distributions and bulk sediment composition to characterize depositional environments and sediment sources.
Applications
- —Grain size analysis — texture and particle size distribution
- —Total organic matter (TOM) by loss-on-ignition
- —Biogenic silica (BSi) by wet alkaline digestion
- —Depositional environment characterization
- —Sediment source and transport pathway analysis
Method Specifications
| Grain Size Method | Laser diffraction particle size analysis |
| Organic Matter | Loss-on-ignition (550°C) |
| Biogenic Silica | Wet alkaline digestion (DeMaster method) |
| Sample Requirement | 1–5 g dry sediment per interval |
Bioindicators — Benthic Foraminifera
Benthic foraminifera are sensitive indicators of bottom-water oxygen conditions, organic matter flux, and environmental stress. Assemblage analysis provides high-resolution records of ecosystem change, hypoxia events, and the impacts of natural and anthropogenic disturbances on seafloor environments.
Applications
- —Benthic foraminiferal assemblage analysis
- —Hypoxia and bottom-water oxygen reconstruction
- —Organic matter flux and eutrophication history
- —Oil spill and contaminant impact assessment
- —Long-term ecosystem change and recovery monitoring
Method Specifications
| Sample Preparation | Wet sieving at 63 µm and 150 µm fractions |
| Count Size | Minimum 300 specimens per sample where possible |
| Taxonomy | Species-level identification with reference collection |
| Deliverables | Assemblage data tables, diversity indices, interpreted report |
Facilities
Laboratory Instrumentation & Facilities
Geochemical Instrumentation
The facilities supervised by Environchron staff include the Bruker Titan XRF (X-Ray Fluorescence) for determining elemental composition of geologic materials, the Rigaku Miniflex 6G XRD (X-Ray Diffractometer) for determining mineralogic composition, and the Malvern Mastersizer 3000+ PRO laser particle size analyzer for rapid determination of particle size distribution.
Sample Preparation Equipment
The lab is equipped with everything necessary for sample preparation and processing, including a Vertis Genesis freeze dryer, planetary ball and McCrone micronizing mills, and a Kendro Heraeus centrifuge for volumes up to 500 ml. General laboratory equipment includes hoods, ovens, analytical balances, a DI water system, and a Muffle Furnace for TOM (LOI) analysis.
Radioisotope Laboratory
Environchron staff supervise a fully functional short-lived radioisotope lab containing Series HPGe (High-Purity Germanium) Coaxial Photon Detectors — 3 planar and 3 well — for sediment age dating by gamma spectroscopy, as well as assessment of geologic materials for radioactivity.
Core Processing & Storage
The team oversees a 1,000 ft² sediment core processing and climate-controlled storage facility utilized for sample storage as well as sample processing workspace.