Characterizing Uncertainties in the Geophysical Properties of Soils in the El Paso, Texas Region
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Developing reliable methods to estimate the uncertainties in the geophysical properties of materials has wide applications across the field of geophysics. Uncertainty estimates aid in helping to devise geophysical sampling schemes, applying inversion techniques to geophysical data and to assess how operator expertise, instrumentation or other factors influence survey accuracy. In this study we evaluate closely spaced geophysical data collected from magnetic, conductivity and gravity surveys over a range of soils deposited in the river valley of the Rio Grande. Our results indicate strong relations between agricultural soil classification and geophysical property variability. They also suggest that power-law processes are of limited usefulness in explaining variability. In addition we found no useful bivariate correlations that would allow us to use a rapid, dense measurement as a proxy for more difficult surveys.
A. Woody, B. Eslick, J. Olgin and A. Wamalwa assisted in the collection of gravity data for this study. The fall 2008 semester “Exploration Geophysics—Non-seismic Methods” class assisted in collection of the conductivity and magnetics data for the well field. C. Montana collected the magnetics data for the alfalfa field. We thank V. Kreinovich for the many fruitful conversations he has had with us regarding estimating uncertainties in geophysical data sets and meaningful ways to analyze the data.
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