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Analysis of the finite-difference time domain (FDTD) numerical simulation of ground penetrating radar (GPR) measurement for locating burial sites is described in this paper. Effective, efficient, and reliability interpretation of GPR field data obtained from clandestine sites is very crucial in forensic investigations. The main goal of the study is the prediction of the change in the interaction of the electromagnetic incident on changes in buried bodies with time. In order to achieve this, the research involves the modeling of the GPR electromagnetic pulse energy responses to simulated changes in buried body with time with a view to understand what the results of real field measurement will give. The field measurements were conducted with GPR system manufactured by Mala Geoscience with antennae frequency of 500 MHz, 250 MHz, and 100 MHz. Responses from both synthetic and field radargrams depict the target was intercepted at same time (approximately 25 ns). The results have demonstrated that FDTD modeling is an important tool for enhancing the reliability of GPR data interpretation particularly for forensic study.

Ground Penetrating Radar (GPR) is one of the most effective and rapid types of geophysical survey methods. The present study was carried out in the Botanical Garden in Kielce, which is currently undergoing a second stage of infrastructure development. This object is located in the Świętokrzyskie (Holy Cross) Region, characterized by large scale deformations in the development of karst origins. Those structures threaten existing buildings and can be obstacles to newly constructed ones. Radargrams presented in this paper show significant potential of the GPR method in mapping of karst phenomena. Proper acquisition parameters and optimal processing of raw data resulted in a clear image of the structure of rock mass under the Botanical Garden, along acquired profile lines. Additionally, precise GPS coordinate links and established researchers' experience of conducting this type of surveys helped in the process of mapping the anomalies in the limestone. Under these conditions, the survey minimized the need for a second method and resulted in high quality data acquisition. The study provided information about underlying rock mass structure development and registered anomalies whose origins include voids or caves of karst genesis. The area studied covers a large part of the Botanical Garden. Described anomalies can be dynamic in origin.

Abstract. Ground-penetrating radar (GPR) is commonly used for locating burial sites. In this article, we acquired radargrams at a site where a domestic pig cadaver was buried. The measurements were conducted with the ProEx System GPR manufactured by the Swedish company Mala Geoscience with an antenna of 500MHz. The event corresponding to the pig can be clearly seen in the measurements. In order to improve the interpretation, the electromagnetic field is compared to numerical simulations computed with the pseudo-spectral Fourier method. A geological model has been defined on the basis of assumed electromagnetic properties (permittivity, conductivity and magnetic permeability). The results, when compared with the GPR measurements, show a dissimilar amplitude behaviour, with a stronger reflection event from the bottom of the pit. We have therefore performed another simulation by decreasing the electrical conductivity of the body very close to that of air. The comparison improved, showing more reflections, which could be an indication that the body contains air or has been degraded to a certain extent that the electrical resistivity has greatly increased.

The Mid-Poland Uplands Belt is a vast area characterized by the presence of carbonate and sulphate rocks. In some parts of this region karst forming and developing processes are dynamic in character. The studied area is the terrain around a historic church in a small village of Szydłów. The building is situated on a hill which is formed by Sarmatian detrital limestone undergoing karst processes. At the foot of the hill there is a number of small caves. Characteristic geological structure and land transformations that are present due to the karst processes prompted the authors to conduct a GPR survey. The aim of this study was to verify whether there is a continuation of caves in the area around the monument. An analysis was made to estimate the risk of damaging the historic building due to the ongoing karst processes. The authors obtained good quality results from GPR measurements. The results confirmed the existence of unknown voids and loosening in rock structure. On radargrams, the authors recorded stratum mapping which confirms the existence of gravitational loosening of the rock mass near the cave ceilings and walls. The results prove that the GPR is an appropriate instrument for mapping some of the karst structures and evaluation of the orogen stability.