Locating Jacob Gens: A subsurface geophysical investigation in Rasu Prison, Vilnius, Lithuania

KLEINSCHMIDT, Alexander S. 1, ERICKSON, James S. 1, SEAMANS, Jackelyn M. 1, WAVRIN, Thomas 1, JOL, Harry M. 1, FREUND, Richard A. 2, REEDER, Philip P. 3 | 1. University of Wisconsin – Eau Claire, 2. University of Hartford, 3. Duquesne University

3D A NALYSIS ABSTRACT PROCESSING • By viewing the grid in a Jacob Gens, a Lithuanian Jewish army officer who held senior leadership 1. In Sensors & Software’s GFP Edit processing program the grid was 3D view the anomaly positions in the Vilnius Ghetto was shot by the Nazis and buried with his oriented so that every transect was of similar length and in the proper X found in line view took journals within the courtyard of Rasu Prison, Vilnius, Lithuania. The and Y directions. form. Circled in yellow objective of the project was to try to non-invasively locate the burial site of 2. The grid was then exported to Sensors & Software’s EKKO Project. In this was the detected Jacob Gens. To search below the grassed prison yard we used a Sensors program each transect can be viewed in line view and slice view. anomaly. The anomaly and Software pulseEkko1000 ground penetrating radar (GPR) system. To 3. In EKKO Project, for better stratigraphic analysis of the data, each detected in the provide adequate depth of penetration, vertical and horizontal resolution, transect was edited so that the gain was set to Automatic Gain Control southwest corner of the grid is interpreted as an antennae frequency of 225 MHz was utilized with a step size of 0.05 m (AGC) and plotted in wiggle traces that are shaded to the right. 4. Exported to Golden Software Voxler the grid was processed into a 3D remains of removed along grid transects. The transects were collected 0.25 m apart with 43 model, which allows for another analysis of objects within the ground in structures (see plan lines in the x-direction and 63 lines in the y-direction, resulting in a 13 x 16 a 3D perspective. VolRender, axes, a bounding box and an oblique base view). m grid. Using EkkoProject and Voxler software programs the collected image were added to the 3D model. transects were collated and processed to provide 2D and 3D views of the datasets. Using radar stratigraphic principles and burial site dimensions of 2 m x 2 m, a possible location has been identified and proposed for future • This anomaly stands out in excavation. RESULTS the 3D grid because there are no above-ground 2D A NALYSIS features suggesting that the subsurface was INTRODUCTION disturbed by any construction of some sort. • Jacob Gens (Jokūbas Gensas, born 1903) was Furthermore, this a Jewish Lithuanian who was a Lieutenant in anomaly proves deep the army during the 1919 Lithuanian war for (1.3m-2.0m) and large independence. enough (2.0m-3.0m) to • In 1941, the Nazis occupied Vilnius, and with accommodate a body. • the Jewish population they created two When looking for a buried object or a body in line view, one should search ghettos. for hyperbolic reflection patterns (Jol & Bristow). • • The lines highlighted in orange are naturally occurring horizontal The Nazis appointed Gens head of the Jewish Jacob Gens ghetto, due to his previous leadership experience. stratigraphic layers. After analyzing each transect of the grid in line view a • As head of the ghetto Gens was responsible for gathering the hyperbolic anomaly within line Y 25 was detected. CONCLUSION /D ISCUSSION individuals that the Nazis wanted and would later be executed. • Gens used his position October 26, 2016 an international to appease the Nazis and team of scientists and excavators allow for a more comfortable returned to the Rasu Prison environment for its residents countyard. Using the data (for example, sporting and provided by the GPR survey they cultural events were held). set up a 2x2 meter grid above the Vilnius detected anomaly and uncovered • September 14, 1943 Gens was called to the the shoulders and skull of a Gestapo headquarters (presently Rasu Prison), • After investigation of a line that crossed line Y25 an anomaly was found in human approximately 1.4 meters is reported to have been killed and buried on The data were collected at Rasu Prison, Vilnius, Lithuania. line X 50 that occurred at approximately the same location. The lines in below the surface (left). site with a boxed filled with his writings and a broken plate. Since the pink are semi-continuous stratigraphic features within a hyperbolic Unfortunately circumstances did ghetto to be liquidated nine days later, Gens’ position was deemed anomaly that may provide details on the burial of Jacob Gens. not allow for the uncovering of unnecessary (Ackerfeld 2006). the rest of the remains. Two teeth • Family members and historians are now interested in finding Gens to PLAN VIEW • A plan view (left) of were taken from the skull for DNA retrieve his papers, gain insight into his involvement, as well as give him the Rasu Prison analyses to see if the remains a proper burial. was created to were Jacob Gens’. DNA results • The objective of this project was to locate Jacob Gens’ potential burial model surface were unsuccessful in identifying if site in the Rasu Prison courtyard non-invasively using ground features that may the remains belonged to Jacob provide clues as to penetrating radar. Gens, however, historical why there are documents provided by the Vilnius areas of high Jewish Museum (email contact) intensity in the states that Gens was buried near METHODS subsurface. two other men. Plans are now • For example, in the underway for further excavation in southwest corner Summer 2017 (left). DATA COLLECTION of the courtyard N there was a large Along with finding human • Ground penetrating area of high remains, a wall was uncovered just radar (GPR) is a device intensity, but there north of the remains. This wall was concreate on used to non-invasively raised questions on what exactly the surface that the anomaly found in the GPR image the subsurface. suggested a survey was. Whether the anomaly We used a Sensors & structure had been was the wall or the fill from a Software pulseEkko1000 SLICE VIEW built there and burial, GPR proved useful in GPR system that uses two removed. locating human remains from the antennae. • Slice view (left) Holocaust. Many more unmarked • The first is a transmitter antenna, which sends electromagnetic (EM) can analyze the burials from the Holocaust still waves into the ground. These waves are reflected by stratigraphic GPR grid in remain in Europe and GPR could be the leading technology to help boundaries and/or various buried objects, which then travel upwards depth slices. This locate further human remains. and are recorded by a receiver antenna (Conyers 2016). By pulling the slice shows high intensity in the GPR across the surface a trigger wheel signals the transmitter antenna northern portion to emit a pulse of EM waves every fixed distance and the reflected N of the grid at the waves are collected and revealed on the display monitor. Using GPR we same depth of searched for the burial site of Jacob Gens. the anomaly REFERENCES /A CKNOWLEDGMENTS • Bristow, C. S., and H. M. Jol. “An Introduction to Ground Penetrating Radar (GPR) in Sediments.” Geological Society, London, Special A 13m x 16m grid was laid out in the courtyard of the Rasu Prison site. found in the Publications 211, no. 1 (2003): doi:10.1144/gsl.sp.2001.211.01.01. • previous line Conyers, Lawrence B. “Ground-Penetrating Radar for Geoarchaeology.” 2016. doi:10.1002/9781118949993. The grid consisted of 43 Y lines and 63 X lines. Ackerfeld, L. "The Terrible Choice." The Terrible Choice. Accessed October 28, 2016. • Data collection used the 225 MHz antennae with a step size of 0.05m views (1.3-1.4 http://www.jewishgen.org/Yizkor/Terrible_Choice/ter002.html. with 0.25m between each transect. meters). Thank you to the International Fellowship program, Philip Reeder, Richard Freund, Harry Jol, the McNair Program and the Diversity Mentoring Program through the Office of Research and Sponsored Programs.