Reconstructing a Romanesque church based on GPR results

We present an integrated prospection of the remains a medieval monastery in Lower Franconia (Germany) built over with a Renaissance castle. The geophysical data is combined with a photogrammetric model of the Renaissance castle. Based on the geophysical data, a virtual reconstruction of the medieval church was achieved

Evaluation of the benefits for mapping faint archaeological features by using an ultra‐dense ground‐penetrating‐radar antenna array

Modern archaeo-geophysical radar surveys are often executed with multichannel antenna arrays, which allows a much faster survey progress combined with a denser profile spacing. Furthermore, from a methodological point of view, a full 3D dataset is necessary to resolve small targets of a few decimetre diameter. However, only a few test surveys deal with the evaluation of the real improvement in data quality by applying such multichannel arrays. In this paper, a test survey with the IDS Stream-C 600-MHz radar device on a small area covering the Roman Bath of Kempten-Cambodunum is presented. The aim of the study is to figure out whether faint archaeological remains like hypocaust pillars, that is, the pillars of a Roman floor heating system, that are missed by single-channel devices, are detectable in an ultra-dense antenna array. Thus, the same area was simultaneously mapped with both GPR configurations. The results of this case study demonstrate the benefit of such antenna arrays for the archaeological prospection of small subsurface features with a diameter of 25 cm or less. For ground-truthing of the results, a comparison with old excavation maps was executed

Comparison of GPR results with UAV photogrammetry at a Roman villa rustica in Noricum (southern Bavaria)

Ground penetrating radar was used for mapping the layout of a Roman villa rustica. Adjacent rescue excavation results were mapped by UAV photogrammetry. The combination with a photogrammetric model enables a ground truthing of GPR result

War related impacts (WRI) in archaeological magnetometer data

The relevance of archaeological prospection in conflict landscape research is briefly outlined. Several examples of WRI in magnetometer data are presented and systematized. For a prediction of filled bomb craters in magnetometer data, respective characteristics are worked out

High-Resolution Direct Push Sensing in Wetland Geoarchaeology—First Traces of Off-Site Construction Activities at the Fossa Carolina

Wetland environments, with their excellent conservation conditions, provide geoarchaeological archives of past human activities. However, the subsurface soil is difficult to access due to high groundwater tables, unstable sediments, and the high cost of excavation. In this study, we present a ground-based non- and minimal-invasive prospection concept adapted to the conditions of wetlands. We investigated the Fossa Carolina in South Germany, a canal that was intended in 792/793 AD by Charlemagne to bridge the Central European Watershed. Although the resulting Carolingian banks and the fairway with wooden revetments are very imposing, archaeological traces of off-site construction activities have not been identified hitherto. Based on a geophysically surveyed intensive linear magnetic anomaly parallel to the Carolingian canal, we aimed to prove potential off-site traces of Carolingian construction activities. In this context, we built up a high-resolution cross-section using highly depth-accurate direct push sensing and ground-truthing. Our results showed the exact geometry of the canal and the former banks. Thus, the magnetic mass anomaly could be clearly located between the buried organic-rich topsoil and the Carolingian banks. The thermoluminescence dating showed that the position of the magnetic mass anomaly reflected Carolingian activities during the construction phases, specifically due to heat exposure. Moreover, we found hints of the groundwater supply to the 5-metre wide navigable fairway

Unsichtbare Spuren der Gewalt sichtbar machen: Erkundungsverfahren der AG Konfliktlandschaften

Mittels geowissenschaftlicher bzw. geoarchäologischer Erkundungsmethoden können Spuren menschlichen Handelns im "Archiv Boden" sichtbar gemacht werden. Auch dann, wenn diese Spuren durch Überdeckung, Verfüllung, Landwirtschaft oder Bewuchs nicht mehr im Gelände nachweisbar bzw. erkennbar sind. Dabei bieten moderne, nichtinvasive Erkundungsverfahren, wie aktive und optische Fernerkundung, Magnetometrie, Georadar und Geoelektrik - vor Allem in Kombination - zugleich einen hohen Flächenfortschr..

Magnetometerprospektion und magnetische Eigenschaften von braunen Plaggeneschen (Oberesch; Lechtinger Esch) und von semiterrestrischen Sedimenten (Fossa Carolina).

Die Magnetometerprospektion gilt mittlerweile als ein Standardverfahren der archäologischen Prospektion. Nicht selten jedoch werden Messergebnisse (Magnetogramme) dieser schnellen und oft ertragreichen Prospektionsmethode ohne eine notwendige Überprüfung im Labor interpretiert, was zu falschen Bewertungen der Magnetfeldanomalien in archäologischen und geoarchäologischen Kontexten führen kann. Die vorliegende Arbeit versucht diesem Problem entgegen zu treten und widmet sich dem Ziel Interpretationen von Magnetometermessungen zu verbessern und Verfahren weiter zu entwickeln, die zur schnellen und hinreichenden Klärung von Magnetfeldanomalien angewandt werden können. Hierfür werden in mehreren Untersuchungsgebieten magnetometrische und umweltmagnetische Messungen in Kombination mit bodenkundlich-sedimentologischen Kennwerten, ausgewertet. Als Untersuchungsgebiete und Umweltarchive stehen die braunen Plaggenesche am Übergang zwischen dem Unteren Weserbergland und der Dümmer-Geestniederung sowie die semiterrestrischen Sedimente des Karlsgrabens (Fossa Carolina) am Übergang zwischen dem fränkischen Keuper-Lias-Land und der fränkischen Alb im Fokus. Magnetometrisch prospektiert wird mit einem, sehr oft bei archäologischen Prospektionen eingesetzten, Vektor-Gradiometer (Bartington Grad601 dual). Als geophysikalische Leitgröße zur Identifizierung und ersten Charakterisierung magnetisch-auffälliger und Magnetfeldanomalien-erzeugender Bodenhorizonte und Sedimentschichten in betrachteten Umweltarchiven wird die magnetische Suszeptibilität herangezogen. Anhand der Curie-Temperatur-Messungen und Domänenstatusermittlungen werden die umweltmagnetischen Minerale und deren Korngrößen in magnetisch auffälligen Lagen und Horizonten charakterisiert. Ergebnisse aus der Kombination umweltmagnetischer Messungen mit Bodenkennwerten an brauen Plaggeneschen weisen darauf hin, dass die in den Plaggenauflagen detektierten, ferrimagnetischen Eisensulfide PSD-Greigite anthropogen induziert sein müssen. Außerdem deutet sich an, dass diese Greigite vom Sicker- und Grundwasser verändert und gegebenenfalls mobilisiert werden können. Ein Vergleich mit Greigiten aus der Literatur zeigt, dass die Plaggenesch-PSD-Greigite in einem Domänenstatus vorliegen, in dem bislang noch keine natürlichen Greigite gemessen wurden. Dieser Domänenstatus wird als ein Oxidationsstadium des ferrimagnetischen Eisensulfids zur Diskussion gestellt. In den Grabenverfüllungen bzw. Paläokanälen des Karlsgrabens wurden in Magnetfeldanomalien-erzeugenden Lagen authigene SD-Greigite nachgewiesen und damit die Annahme von Stanjek et al. (1994) bestätigt, dass die Greigite für die Magnetometerprospektion in semiterrestrischen Umgebungen von Bedeutung sein können. In flankierende Begleitstrukturen des Karlsgrabens wurden hingegen hocherhitzte, thermoremanente PSD-Titanomagnetite als Magnetfeldanomalien-Erzeuger ermittelt. Ihre Entstehung bleibt ungeklärt, jedoch wird eine natürliche Bildung dieser Magnetominerale vor Ort ausgeschlossen. Im Hinblick auf das Ziel der vorliegenden Arbeit hat sich die methodische Vorgehensweise am Karlsgraben als besonders effiziente und relativ kostengünstige Methode zur abgesicherten Klärung von Magnetfeldanomalien in den Magnetogrammen gezeigt

Large-scale UAV magnetometryon a former World War II airfield at Ganacker(Lower Bavaria, Germany)

In the last few years, several Unmanned Aerial Vehicle (UAV) based magnetometer systems have been tested for archaeological prospection. Due to their higher sensitivity, scalar magnetometers have been preferred as test sensors. However, total field magnetometer are vulnerable to disturbances, especially those generated by the UAV itself. Therefore, most UAV scalar magnetometer systems use the method of increasing the distance between magnetic sensors and the UAV to reduce interference. But freely suspended sensors tend to swing on ropes under the UAV and can produce data that are strongly influenced by heading errors. For our test, we therefore chose the UAV-fixed, compact setup of the SENSYS MagDrone R4, which is equipped with five three-axis FGM3D/75 fluxgate sensors at 50 cm spacing and is covering a swath width of 2.5 m. The 200Hz sampling rate of the R4 allows easy filtering of interference generated by the UAV and external disturbances like power lines or infrastructure. Magnetograms with a spatial resolution of up to 0.20 m per pixel were produced from the data. At Ganacker, we chose the former infrastructure core of the World War II German Air Force airfield as a test site. A wide range of archaeological structures and features with high magnetic contrast were expected on this area. The test site is currently an open agricultural area with a quite flat terrain. Hence, the R4 could be operated at a fixed flight height of just one metre above the surface of the terrain that is controlled actively by a radar sensor. An area of around 110 hectares were prospected within only four days. The MagDrone R4 system thus offers an outstanding survey area progress that cannot even reached by common vehicle-moved multi-sensor arrays. Here, we present the first results of this test survey by comparing the magnetograms, historical and current geodata. Most of the expected archaeological features and several unknown ones were detected by the R4 system. Our results show that the R4 system is well suited for mapping large archaeological structures with high magnetisations. In the future, we want to compare the R4 data with data from a ground-based fluxgate magnetometer. We also want to test whether the system is suitable for detecting archaeological features that have lower magnetic susceptibility and remanence contrasts with the surrounding soil.poste

Holocene sediment dynamics in the vicinity of a roman battle field near Osnabrueck (NW-Germany)

The interpretation of the Holocene sediment dynamics at Mount Kalkriese in the Wiehengebirge mountains (northwestern Germany) shows that the onset and the extent of human land use corresponds well with most colluvial archives in Central European loess regions: The onset of soil erosion in the Wiehengebirge mountains started during the Early Neolithic period. For the Bronze Age, erosion and colluviation are documented as well. A considerable increase of soil erosion with correlated reworking of colluvial sediments was found since Roman times, indicated by the burial of Germanic artifacts of Roman Age at the toe-slopes. Unfortunately, no absolute ages exist for the post roman period. However, in analogy to other sites it can be assumed that highest erosion rates occurred during the Middle Ages. This study also shows typical problems when using the soilscape model for calculating the sediment budget: since truncated soil profifi les are used to model eroded volumes, only minimum soil erosion is mapped. This can lead to a considerable discrepancy between eroded and accumulated volumes. Therefore, we have to assume that soil erosion at the plateau and in upslope areas at Mount Kalkriese was much higher than predicted by the soilscape model. In addition, extensive anthropogenic accumulation soils (Plaggen soils) were deposited in the downslope areas, thereby increasing the discrepancy between erosion and accumulation volumes. The combination of mapping erosion and accumulation with augerings and trenches, calculation of the mass balance by GIS, relative and absolute dating and geophysical evidence provides a powerful tool in landscape interpretation. Due to the small number of numerical ages, the landscape model at Mount Kalkriese has to be considered preliminary

Testing the advantages of ultra-dense GPR antenna arrays for the Archaeological Prospection

During the last few years, the use of Ground-Penetrating-Radar (GPR) multi-channel antenna arrays in the Archaeological Prospection increased dramatically. The main advantage of this type of survey is a much faster data acquisition combined with a dense profile spacing. However, most of the common multi-channel arrays consist of antennae with a spacing of not smaller than 8 cm. The aim of our test survey was to evaluate how an even denser spacing of 4 cm that is provided by the IDS Stream-C GPR device at a centre frequency of 600 MHz can improve the detection of small archaeological features. As a test site, we chose the Great Bath in Kempten-Cambodunum. This first capital of the Roman province Rhaetia never has been overbuilt in the following centuries and even today it is used as a grassland declared as an Archaeological Park. Already in 1911, the Great Bath was excavated and beside the walls of different building phases, also small features like a multitude of hypocaust pillars were unearthed. Hence, this building structure depicts an ideal test site and a 40x40m grid covering the main part of the construction was chosen for the application of the antenna array. As a comparison, the same grid was contemporaneously surveyed with a single antenna IDS Duo device (600 and 200 MHz) and a 50 cm profile spacing. Regarding the walls of the Roman bath, the two surveys show comparable results: both datasets represent the stone constructions of 50 – 90 cm width quite well. Furthermore, the depth slices of both devices provide a differentiation of the single building phases. Nevertheless, the resolution for the multi-channel antenna array is of course much higher due to the denser profile spacing. Huger differences occur for the hypocaust pillars of 25 cm lateral length. These features can be mapped in detail with the 4 cm profile spacing of the IDS Stream-C system. Whereas the IDS Duo can only resolve some of the hypocausts, a multitude of them gets visible between 70 and 110 cm depth in the Stream-C data. As a conclusion, it can be stated that standard archaeological remains like stone walls, for sure, can be surveyed with single antenna GPR devices in a common profile spacing of 50 cm. However, in case of the existence of faint archaeological features the application of ultra-dense antenna arrays like the IDS Stream-C is advisable to get a comprehensive overview of a site without the necessity to excavate them.poste