Repository logo

Radioisotopic sand tracer study, Point Conception, California : preliminary report on accomplishments : July 1966 - June 1968

Thumbnail Image




Duane, David B.
Judge, Charles W.

Journal Title

Journal ISSN

Volume Title


Coastal Engineering Research Center (U.S.)


The purpose of the Radioisotopic Sand Tracer (RIST) study is to develop and use radioactive tracer methods for research in sand movement and littoral processes. Research objectives include determination of suitable radioactive isotopes, development of mobile and stationary radiation detectors, and development of suitable handling and survey programs. Concurrent with these objectives, studies of sediment transport around the Point Conception headland and of the mechanics of littoral transport are being conducted. Methods developed by this program have direct application to engineering design of such works as harbor development and beach erosion prevention, and quasi-military application such as the location of radioactive or other toxic materials. To date, sand grains indigenous to the study area have been labeled with xenon-133 which does not adversely affect the hydraulic properties of the sand. Various devices and methods of employing the tagged sand have been studied. A mobile detector system using cesium iodide crystals and housed in a "ball" towed behind an amphibious vehicle detects the quantity and areas of radiation. Computer programs have been developed to correct and plot radiation data. A field test of equipment and principles at Cape Kennedy, Florida, were successful. Additional field tests were at Surf and Point Conception, California. These tests included isotope distribution, sediment analysis, offshore profiles, and oceanic and atmospheric environment monitoring. In addition, model tests were conducted in the Shore Processes Test Basin at the Coastal Engineering Research Center (CERC) to compare high and low specific activity xenon, and to study beach development and movement under the controlled conditions of a hydraulic laboratory. The data density is sufficient to support tentative conclusions regarding offshore sediment movement in the Point Conception area. Additional field tests will extend the survey from the beach through the surf zone. In addition, development of instruments and field programs will continue in order to permit their routine use by technicians and field crews.


Miscellaneous Paper


Conception, Point (Calif.), Radioisotopes, Sediment transport


chat loading...