| ABSTRACT: | DESIGN OF AN IN-SITU RADIOGRAPHIC SYSTEM FOR IMAGING MARINE SEDIMENTARY
STRUCTURES
M. R. Khan, E.M.A. Hussein and M.K. Gingras
University of New Brunswick, Fredericton, N.B., Canada
The current practice for imaging marine sediment structures involves x-raying, in the laboratory, extracted
core samples. This engages a number of tedious and intrusive processes that may alter the original structure
conditions of the sediment. An in situ imaging technique can overcome these problems, as well as increase
the reliability, effectiveness and speed of inspection. This paper presents the design aspects of such a system,
which takes advantage of the small-size and self-powered nature of isotopic sources. The design process
involved: the selection of a source that provides maximum contrast for a given thickness of object; the
determination of the source-to-object distance that reduces image unsharpness; and the source-film
arrangement that provides such contrast and sharpness. In addition, the effect of radiation scattering of
sediment present behind the inspected volume is assessed, and the most suited film is recommended. The
goal was to design an in-situ radiographic system that provides the same image quality as conventional
methods currently in use. The design process was based on Monte Carlo analysis due to the lack of available
standards for such new imaging system. In addition mock-up experiments were conducted to verify the
design. A conceptual design of a device suitable for use in the field is presented.
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