Archaeological Prospection最新文献

Geophysical methods, and particularly ground penetrating radar (GPR), have been increasingly applied as a preliminary mapping tool to guide archaeological excavations. Direct comparisons between geophysical and archaeological features are however not always systematically performed given the different time spans, covered areas, acquisition and processing approaches of the surveys. A critical comparison between geophysical and archaeological results is here proposed on a test site within the archaeological area of Augusta Bagiennorum (NW Italy). Three rectangular sectors covering an area of approximately 2325 m² were investigated with high-density GPR profiles and compared with both historical and new archaeological excavations. The GPR amplitude and attribute analyses highlight the effectiveness of geophysical prospections in identifying buried linear (i.e., walls) and localized (e.g., pillars or columns) archaeological remains. The recent archaeological excavations fully confirm the interpretation of the GPR results. Historical archaeological trenches, filled with coarse material after the excavation, are also found to generate strong anomalies in the GPR amplitude, similar to the ones of the buried structures, but with irregular contours and oblique orientations with respect to Roman remains. The GPR prospections also highlight interesting buried elements in unexplored areas, supporting important archaeological interpretations about the spatial configuration of the Roman city. The results help to recognize sectors with significant and well-preserved buried remains that can be brought to light in the future to promote heritage conservation and enhancement at the site.

The article presents the results of magnetic and ground-penetrating radar (GPR) research carried out in Old Dongola in northern Sudan in 2018 and 2020, within the framework of a project designed to investigate the transition from Christianity to Islam taking place in the capital of the Nubian kingdom of Makuria. The integrated datasets from the application of two geophysical methods, of which one is the standard magnetic method used on sites in the Nile Valley and the other ground-penetrating radar, enhanced the archaeological interpretation, focused in this case on a reconstruction of the urban layout of the 16th–18th-century Funj settlement within the walls of the Dongola Citadel. The magnetic method, the effectiveness of which has gone unquestioned with regard to the study of silt architecture in the Nile valley, was successful in mapping the general outline of the settlement on the Citadel hill and in the quarter north of the walls. The GPR survey (450-MHz antenna) provided a much more detailed image of the street grid and was much more effective than the magnetic method in tracing the course of mud-brick walls in a sandy matrix containing baked brick rubble. Verification of the geophysical results through the excavation of selected parts of the Citadel not only satisfied the objectives of the archaeological project, which was to establish the overall street and building layout in the research area, but also confirmed the effectiveness of the two prospection methods applied in combination and the potential of integrated research with the use of the GPR and magnetic methods for the study of mud-brick and baked brick architecture on settlement sites in Sudan.

The archaeological zone of Huexotla, east of Mexico Basin, was part of the Acolhuacan lordship, associated to the Mexica domain in the Postclassical period. In this site, several structures have been partially explored, some of which are open to the public. Recent explorations led to the hypothesis that the structures of La Estancia, the Wall and the Community were part of a more complex space that formed the Sacred Precinct of the city. In order to test this postulate, magnetometry was conducted in three areas of the site. By processing Total Field and Vertical Gradient magnetic data, we were able to identify and understand the distribution of underground features like walls, floors and platforms, aiding in the determination of potential excavation areas. Processing the magnetic data with the application of the analytic signal operator allowed more information to be acquired for the recognition of structures of interest. The geophysical results were correlated with the outcomes of archaeological excavations in three structures, confirming the existence of architectural patterns that were not previously detected and supporting the thesis proposed for the ceremonial enclosure.

The article presents the latest results of the search for the first location of abandoned medieval town Toruń (Ger. Thorn), conducted in 2017–2018 by an interdisciplinary research team. Noninvasive research, including aerial, surface and geophysical prospection and geological soil coring, was preceded by archival and library queries and analysis of historical written and cartographic sources as well as contemporary remote-sensing digital images. These all pointed clearly to an area to the west of Toruń, north of the entrance to the Wood Port on the Vistula. A systematic aerial survey led to the discovery of an extensive anthropogenic structure in this area. Magnetic gradiometry survey revealed anomalies typical of human activity that were interpreted as, among other things, the remains of moats and buildings indicating the area of the town's first location. Their physical character was confirmed through geological tests. Moreover, the existence of an embankment surrounding the town is suggested by the traces of an alluvial fan formed within the fortifications by flooding. The authors point out the limitation of the possibility to identify such sites by field walking-method within the methodology of the Polish Archaeological Record. The acquired results provide strong grounds for a continuation in the form of further interdisciplinary archaeological research.

Electrical resistivity tomography (ERT) and ground-penetrating radar (GPR) were collected on the eastern side of the northern Ishtar gate in ancient Babylon, Iraq, to locate the palace wall and other surrounding walls. Due to the presence of a low resistivity (highly conductive) top layer associated with brick rubble and other debris, the GPR reflection profiles show a high-energy attenuation, but a series of processing and filtering steps produced coherent reflections of about 2 m depth. Profile analysis shows the geometry and layering of the walls and the surrounding matrix. With the ERT, the surface conductive zone produces various distortions in ERT inverse models, making identifying the features' lower boundaries difficult. Here, we suggest that instead of analysing these two data sets independently, the integration of both reveals not just the walls but their composition and defines material in the surrounding units. This integration shows how the interpretation of the shallow features on the 3D ERT maps is improved by comparison and interpretation in conjunction with the reflections visible on both reflection profiles and the 3D GPR amplitude slices. The orientation of these features and reflections emphasizes the existence of one series of buried walls at a depth of 90–150 cm. The thickness of these walls varies between 0.25 and 1 m. Another wall-like feature is visible only on 3D ERT maps and not with the 3D GPR slices at 2 m depth, which indicates a thickness of 11 m. It is interpreted as the palace wall, which is consistent with earlier archaeological excavations. An analysis of the geometry and composition of both wall components, perhaps of different ages, and constructed for different reasons, indicates that some shallower walls may be the remains of rooms built as residences for soldiers, or they may belong to the other ruins of northern Ishtar gate.

Geophysical investigations have become standard in archaeological practice to map sites and help select location for excavation, but the application of these techniques in real time during excavation to help anticipate feature location and maximize recovery has not been developed. This paper presents results from both traditional geophysics and new approaches to using these methods during excavations at Rice Farm (9DW276), a Middle Woodland site located in a broad floodplain adjacent to the Etowah River in north Georgia. Ground penetrating radar (GPR) at the surface was effective in recording reflection events indicative of archaeological features, such as hearths, posts and possibly ditches. Magnetometry was helpful, but less effective due to heavy plough zone scarring and noise from modern metallic debris. High-frequency handheld GPR was helpful in monitoring excavations in real time and assisted excavators in anticipating the locations of both large and small diameter features. Excavation of geophysical anomalies exposed important features for the interpretation of this newly documented site.

This paper tests the applicability of an unmanned aerial system (UAS) in obtaining spatial data from archaeological sites in forested areas. Our case study discusses the remains of the anti-Turkish fortifications called ‘Turške Šance’—the defensive ditches that are preserved in the area of the Preški vrh (Ravne na Koroškem, Slovenia). Up to 10 fortifications of various shapes and sizes were built in the last quarter of the 15th century. Today, they represent a unique archaeological site. A detailed geodetic survey of the site was performed and compared with results of photogrammetry using the DJI Phantom 4 PRO UAS drone and DJI Phantom camera. Furthermore, official Slovenian LiDAR data of the area were obtained, and archaeologic field surveys, in situ inspections and metal detector scanning were made. The points obtained from the total station were used for 3D modelling and taken as a reference. Drone photogrammetry was performed once per week to compare each point cloud with another using CloudCompare and to the reference one depending on the volume of the tree leaves which was estimated with green leaf index (GLI) and leaf area index (LAI). The increase of the tree leaves volume deteriorates the point cloud obtained with a UAS. The paper analyses how significant this influence is. As expected, the impact grows more severe with the increase in leaf mass from week to week.

The determination of the natural remanent magnetization (NRM) of archaeological features can be used for magnetic modelling, joining of shards, archaeomagnetic dating or the investigation of the firing–cooling–collapsing order of ancient buildings. The measurement of NRM is normally conducted on cylindrical or cubic samples in the laboratory. Nevertheless, archaeological finds should preferably not be destroyed, and laboratory instruments are high in costs. Therefore, we propose a lightweight and portable measurement set-up including already available field magnetometers (preferably caesium magnetometers) in which the archaeological sample of arbitrary shape, in our case a piece of daub, is mounted inside a gimbal to be rotated in all directions. The magnetic field of the sample is measured at a large number of rotational positions with the magnetometer kept at fixed position. In these measurements, the unknown direction of the NRM vector of the sample is rotated, whereas the average magnetic susceptibility of the sample and the ambient magnetic field are constant and known. Hence, the vector of NRM can be determined through least-squares inversion. For the inversion computation, the sample volume is discretized either as voxel model or approximated as an equivalent sphere. Under certain conditions depending on sample–sensor distance, dipole moment and radius of the sample, the approximation by a sphere is valid without effect on the accuracy of results. Empirically determined functions quantifying these conditions for different sensor sensitivities and noise levels are provided. Validation with laboratory measurements on palaeomagnetic subsamples from the destroyed daub samples indicate that the NRM can be determined by our proposed method with a maximum error in inclination of 2°, in declination of 20° and in magnetization of ±0.6 A/m. This is accurate enough, for example, to determine from daub pieces of burnt house remains whether the building was burnt and cooled before or after it collapsed.

The cessation of most human activities resulting from post-World War II expulsions and forced displacements in Central Europe triggered massive land cover transformation in mountainous areas. However, many pre-War traces of past landscapes have survived—imprinted in microtopography—in permanently abandoned villages. Currently, they constitute unique cultural heritage of communities no longer in existence. Our main goal was therefore to reconstruct a lost cultural landscape of mountain villages abandoned after World War II (WWII). The case study area comprised three such villages located in southern Poland, two in the Carpathians and one in the Sudetes. We used the national airborne light detection and ranging (LiDAR) dataset combined with archival cadastral maps and field survey to detect man-made microtopographic features related to past boundaries, road network, agriculture and buildings and to interpret them in the landscape context. We demonstrated that the pre-War human footprint left in relief was shaped largely by past landownership divisions, land use and environmental constraints (related to lithology, soils and topography). Our secondary goal was to assess the value and application opportunities of LiDAR in reconstructing past landscapes. We showed that 38–70% of non-natural parcel boundaries and 65–79% of roads marked on mid-19th-century cadastral maps are still detectable using LiDAR. Therefore, we argue that the past landscape pattern, originating in late Middle Ages and subsequently transformed prior to WWII, remains well preserved in the relief and that LiDAR is an effective tool to reconstruct a past landscape of mountain villages abandoned after WWII. We also confirmed that customized LiDAR visualizations are more informative than ready-to-use shaded digital elevation models (DEMs), in particular when integrated with cadastral and field-based data. We conclude that the greatest advantage of LiDAR is the capacity to provide a landscape context for isolated traces of past human activity, allowing for the reconstruction of entire spatial patterns and interrelationships developed by past societies.