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Kansas Geological Survey, Current Research in Earth Sciences, Bulletin 247, part 1
Modeling Dielectric-constant Values of Geologic Materials: An Aid to Ground-penetrating Radar Data Collection and Interpretation--Fig. 12


Fig. 12. Calculated reflection coefficients for dry and water-saturated, two-layer models plotted against the percentage of quartz in the lower layer. The upper layer is 100% quartz with a 20% porosity, and the lower layer is calcite with variable amounts of quartz and a 20% porosity. The shaded area indicates power reflectivity values of less than 0.01, a conservative estimate of the threshold at which background noise may preclude recording of reflection information (i.e., SNR less than or equal 1; Annan, 1996). The effect of mineralogy on reflection coefficients is less than that due to porosity (fig. 11). [****Delete last sentence?? Seems like this should be stated in the text rather than in the fig. caption.****]



Kansas Geological Survey
Web version December 3, 2001
http://www.kgs.ku.edu/Current/2001/martinez/fig12.html
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