Photo Gallery for Clarke County, Virginia

Clarke County Photo Gallery Age Dating
FILE: age03.jpg
DESCRIPTION:
Collection of chlorofluorocarbons (CFCs) age-dating sample. The borosilicate ampoule is flame-sealed to prevent contact with gases in the atmosphere at the time of sampling. The headspace in the ampoule is filled with ultra-pure nitrogen gas. The ampoule is opened in an apparatus that is filled with ultra-pure nitrogen and the sample water is injected into a gas chromatograph with an electron-capture detector at the USGS Reston Chlorofluorocarbon Laboratory in Reston, Va.. Detection limits are a part per quadrillion.



SOURCE: David Nelms USGS

Current Water Conditions for Clarke Co.

The USGS provides current ("real-time") stream stage and streamflow, water-quality, and ground-water levels for 4 sites in Clarke County, Va.

The USGS provides current ("real-time") stream stage and streamflow, water-quality, and ground-water levels for 35 sites in the Shenandoah Valley of Virginia and West Virginia.

U.S. Department of the Interior | U.S. Geological Survey
URL: http://va.water.usgs.gov/clarke/PHOTO/AgeDating/age03.htm
Page Contact Information: webmaster-va@usgs.gov
Page Last Modified: 28-Feb-2008 14:00:00 EST