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https://hdl.handle.net/11681/11593| Title: | Nuclear measurement of snow density |
| Authors: | Leighty, Robert Dwaine, 1930- |
| Keywords: | Snow Stratigraphy Snow stratigraphy Snow sampling Snow density Nuclear measurement Ice Ice density |
| Publisher: | Cold Regions Research and Engineering Laboratory (U.S.) Engineer Research and Development Center (U.S.) |
| Series/Report no.: | Special report (Cold Regions Research and Engineering Laboratory (U.S.)) ; 74. |
| Description: | Special Report Summary: During the period 8-19 May 1963, a preliminary field investigation was conducted in Greenland to determine the feasibility of using a nuclear technique to determine snow and ice density profiles. Two modes of processing and recording nuclear pulses from a standard nuclear soil moisture depth probe were used. In the scaler mode, the probe is lowered to a selected depth and the counts are made with the probe stationary for the duration of the count period. Repeating this procedure at different depths allows construction of a depth-count rate curve. The second mode utilized the rate meter-recorder in combination with the nuclear probe. The rate meter converts random pulses from the probe into an average count rate for presentation on the external chart recorder. A continuous profile of count rate versus depth results from simultaneous travel of the probe in the hole and the recorder chart. Examples containing data obtained by both modes are presented and discussed. A correlation between snow density and nuclear count rate was hampered by lack of ability of the field party to obtain representative density samples. However, there is a general fit to a regression curve obtained by another investigator. Curves were constructed for statistical deviations in snow density at different probability levels for the nuclear scaler and rate meter data based on an assumed correlation curve. These curves demonstrate that the nuclear technique has possibilities of producing the statistical accuracy required for determining snow density profiles. The nuclear method was found to be feasible; however, deficiencies related to poor resolution render the probe unusable for detailed profiling of snow stratigraphy in its present form. The system is detector-limited but progress in the state of the art of nuclear and electronic engineering will soon enable improvement of both resolution and accuracy by improvement of nuclear detectors. A rapid method of accurately determining depth-density variations in snow would be a valuable tool to the engineers and scientists interested in snow stratigraphy, water equivalent of the snow pack, depth-density variations, etc. |
| Rights: | Approved for public release; distribution is unlimited. |
| URI: | http://hdl.handle.net/11681/11593 |
| Appears in Collections: | Special Report |
