Key Words: Ground Penetrating Radar, Clandestine Burials, Geophysical Applications in Anthropology, Historic Cemeteries introduction and purpose
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| Figure 3. Distribution of Florida soil orders (http://waterquality.ifas.ufl.edu/GIS/Soil%20images.htm) The seven soil orders of Florida are the Alfisols, Entisols, Histosols, Inceptisols, Mollisols, Spodosols and Ultisols (Table 4). Of these, only the Entisols and Histosols are devoid of either clayey substances or medium to high soil cation exchange. This does not preclude the applicability of GPR surveys in other locations, nor necessarily suggest that these are the only soil orders available for GPR research. Indeed, Histosols are representative of excessively wet environments where the upper layer of soil is composed of partially decomposed plant remains essentially muck (Collins, 1985). Moreover, some recent studies have shown the efficacy of GPR in clayey soils despite previous evidence otherwise (Schultz et al., 2006; Pringle et al., 2013; Lowe et alas will be discussed later. The important factor for GPR surveying appears to be a sound knowledge of both the equipment and the environment as well as an understanding of proper post-processing procedures. A basic understanding of soil science is necessary to the proper use of GPR in afield survey. Failing to note properties in soil that may cause a rapid attenuation of radar energy has the ability to make a survey fruitless. By garnering as much information of a site’s formational processes and understanding the capabilities of the GPR equipment and post-processing procedures, it maybe possible to expand the role of GPR in future surveys. Table 4. The seven soil orders of Florida, their characteristics, and percentage of land cover. Adapted from (Collins, 1985). Soil Order Description Percentage of Land Cover Alfisols Argillic horizon, medium to high mount of bases in soil, water generally available to plants, ochric epipedon. 4.6 million acres Entisols Does not reflect major set of soil-forming processes, form in inert parent materials such as quartz sand or limestone. Absence of distinct pedogenic horizons except for ochric epipedon, albic horizon, and a spodic or argillic diagnostic subsurface horizon below 80 inches. 7.5 million acres Histosols Very high organic carbon in upper 32 inches. Most formed from partially decomposed plant remains accumulated in water. Peat or muck. 4.0 million acres Inceptisols Moderate to high cation exchange capacity in the clay fraction. Dark, thick, and low base saturation surface horizon. 1.0 million acres Mollisols Dark, brown surface horizon, high amount of calcium versus other extractable cations present in the soil, and clay minerals of moderate or high cation-exchange capacity. Poorly drained. 1.0 million acres Spodosols Have undergone soil process that translocate organic matter, aluminum, andiron as amorphous materials. Spodic horizon, accumulation of black or reddish amorphous material having a high cation-exchange capacity. Poorly drained. 8.4 million acres Ultisols Argillic horizon, but more leached than Alfisols. Low supply of bases and usually enough moisture for crops yearly. 6.9 million acres |