The Stone Cold Truth: The Effect of Concrete Encasement on the Rate and Pattern of Soft Tissue Decomposition

Abstract

This study provides a descriptive analysis of taphonomic changes observed in the soft tissue of ten pigs (Sus scrofa) after being encased in Quickrete (®) concrete and excavated at monthly or bimonthly intervals over the course of 2 years. The best method of subject excavation was investigated. Rate and pattern of decomposition were compared to a nonencased control subject. Results demonstrate subjects interred in concrete decomposed significantly slower than the control subject (p < 0.01), the difference being observable after 1 month. After 1 year, the encased subject was in the early stage of decomposition with purging fluids and intact organs present, versus complete skeletonization of the control subject. Concrete subjects also display a unique decomposition pattern, exhibiting a chemically burned outer layer of skin and a common separation of the dermal and epidermal layers. Results suggest using traditional methods to estimate postmortem interval on concrete subjects may result in underestimation.

Dismemberment and Body Encasement—Case Report and an Empiric Study

“…A similar finding to ours was the black discoloration of the outer skin layer and the separation of epidermis and dermis due to chemical ‘burning’ by the concrete [ 29 ]. This can be explained by the high proportion of calcium oxide in the concrete, which is largely basic and undergoes an exothermic reaction upon contact with water [ 31 ].…”

“…In the studies by Martin et al [ 29 ] and Gibelli et al [ 30 ], the pigs were also encased in concrete and decomposition was measured at different times according to the TBS and the different stages of decomposition. As in our study, temperature, total precipitation, wind speed, and relative humidity were measured.…”

A proposal for a White Paper on Geoethics in Forensic Geology

“…Spades and vehicles are also very good potential sources of evidence (Melo et al, 2019). A range of earth materials have been characterised in a forensic manner, including concrete (Martin, 2016), lead (Bond et al, 2013), gold , nickel (Roelofse and Horstmann, 2008), zinc ingots (Salvador et al, 2019) and glass (Seyfang, 2015).…”