Instrument measures elemental abundance and isotopic ratios in samples as small as a few nanograms. Uses include geochronology, geological thermometry, and trace element geochemistry of geological and biological materials.
Manual of chemical sediment analysis using Coulometer and CHN Analyzers to measure carbon content, spectrometric analysis for biogenic silica, and radiochemistry to measure isotopes. Includes techniques,sample preparation, and safety procedures.
Report of research on the Carolina slate belt and gold deposits in Virginia, North Carolina, South Carolina, and Georgia with geologic mapping, mineralogic, geochemical, and fluid evolution studies, radiogenic dating, and stable isotope studies.
Explains the important paleoclimatic information we have obtained from this subaqueous cavern. The time-series data show important contrasts with what would be predicted from orbital theory, provoking extensive scientific discussion.
Direct measurement of an important indicator of interannual variability is extended, using geological proxy measures, farther back in time to well before modern measurements were made. This tells us about the history of climate variability.
Brief review of some of the fundamentals of stable isotope geochemistry including definitions, basic principles, standards, and guidelines on reporting data.
Overview of chemical analyses, tracer studies, gas geochemistry, stable isotopes analyses, organic chemistry, and thermometry capabilities at major USGS laboratories with links to technique, equipment, and contacts for each procedure.
Description of the methods of geochronology used to estimate the dating of rocks and sediments with links to technique, equipment and contacts for a variety of methods.
Booklet giving general explanations of geologic time, major divisions of geologic time, relative and radiometric time scales, index fossils, and the age of the earth.