Determining geophysical responses from burials in graveyards and cemeteries

Abstract

19Graveyards and cemeteries around the world are being increasingly designated as full. 20There is a growing requirement to identify burial spaces or to exhume and then re-inter 21 burials if necessary. Near-surface geophysical methods offer a potentially non-invasive 22 target detection solution; however there has been lack of research to identify optimal 23 detection methods using such geophysical techniques. This study has collected multi-24 frequency (225 MHz -900 MHz) ground penetrating radar, electrical resistivity and 25 magnetic susceptibility surface data over known burial sites with different burial ages and 26 UK church graveyards. Results indicate that progressively older burials are more difficult to 27 detect but successful grave detection is complicated by soil type. Different geophysical 28 techniques were optimal in the three sites surveyed, which therefore suggests a multi-29 technique approach should be utilised by survey practitioners. Graveyard geophysical targets 30 included the grave soil present above earth-cut graves, the grave contents themselves, brick-31 lining (if present) and grave soil leachate plumes that are all geophysically detectable from 32 background levels. Grave markers were also identified as not always being located where the 33 burials were positioned. This study clearly demonstrates the value of these techniques in 34 grave detection and inform search teams detecting clandestine burials. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 Globally, graveyards and cemeteries are suffering from a severe lack of burial space. 42With an estimated 55 million individuals dying globally each year (de Sousa, 2015), the 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 (Reynolds, 2011; Pringle et al. 2012a Pringle et al. /2016 Gaffney et al. 2015). Electrical resistivity 77 surveys have been successfully used to locate unmarked burials in cemeteries (see, e.g. 78Matias et al. 2006; Hansen et al. 2014; Buyuksarac et al. 2015). Controlled studies on 79 modern burials evidencing that decompositional fluids may be the dominant factor in graves 80 that is detected electrically (see Jervis et al. 2009; Pringle et al. 2012b), and may be retained 81 in grave soil for considerable periods of time post-burial (see Pringle et al. 2015a). However, 82it is important to note that the style of formal burials and clandestine graves of murder 83 victims are usually quite different in terms of structure, depth and complexity of the burial 84 contents (Fig. 1). Apart from graveyards and cemeteries being reused, partially excavated, 85topsoil removed, etc. the graves present can also vary in style from earth-cut (as shown in 86 Fig. 1) to...

Comprehensive Geophysical Study at Wabar Crater, Rub Al‐Khali Desert, Saudi Arabia

“…GPR has been used in many applications, for example, to detect shallow anomalies (Dick et al., 2017; Hanafy, 2010), detect bubbles in ice lake (Fantello et al., 2018), image subsurface layers (Chen et al., 2016), and determine soil‐moisture heterogeneity (Hanafy & Hagrey, 2006). GPR surveys are not usually used to investigate crater impact sites due to its limited depth of penetration.…”

Portable X-Ray Fluorescence (pXRF) Analysis of Heavy Metal Contamination in Graveyards with Contrasting Soil Types

“…3). The reason these two were studied is that they have over known burial records from over 500 years to the present day, contrasting soil textures (site 1 is sandy and site 2 is clay-rich soils respectively), bedrock types, rainfall levels and geographic settings (semi-urban and rural respectively) which make a useful contrast for this study (Dick et al, 2017).…”

“…Non-invasive geophysical studies in such burial grounds indicate elevated conductivity levels in grave soil (Hansen et al, 2014), with individual grave geophysical anomalies decreasing with increasing burial age, when compared to background values. However, soil texture and moisture content have been shown to be major variables with sandy soils causing leaching of grave contents well beyond the grave-cut, whereas clayrich soils tend to retain these uids within the grave-cut itself (Pringle et al, 2012(Pringle et al, , 2016Dick et al, 2017).…”

Geophysical monitoring of simulated homicide burials for forensic investigations

“…These contrast with (e) isolated graveyard/cemetery earth-cut burials which have quite different style/depths etc. Modified from 14,47 . potential recovery 7,23 .…”

“…However, at present, a detailed understanding of the temporal persistence of the post burial geophysical anomaly remains unknown due to the time and effort required to collect control data over many years. Geophysical responses from recent (<10 years) clandestine burials are known to vary more than archaeological graves 47 so an understanding of temporal change is important. Potential reasons for this change could be the modification of grave soil after burial, influence of decomposition products 48 , climatic/weather induced variations of soil moisture content 49 , or indeed burial style -see Fig.…”