Buried Archaeological Features Research Articles

Lembah Bujang is well-known for its cultural heritage, comprising a vast variety of archaeological structures and artifacts that could potentially offer valuable insights into the area’s historical timeline. However, identifying buried archaeological features via geophysical surveys is a complicated process that necessitates a comprehensive comprehension of both physical properties and archaeological knowledge. To overcome this challenge, a research project was conducted to detect clay brick structures using an integration of geophysical methods such as magnetic and 2-D resistivity at two separate locations within the SB2ZZ and SB2 sites. The research discovered two primary types of archaeological features for these areas, which are mound surfaces and scattered exposed clay bricks. The magnetic data was processed to identify potential clay bricks, which were then confirmed using 2-D resistivity. At the SB2ZZ site, excavations uncovered buried clay brick structures, which reinforced the interpretation of geophysical findings. Both SB2ZZ and SB2 sites demonstrated that clay bricks typically exhibit high magnetic anomalies and resistivity values ranging from 50-140 nT and 400-1000 Ωm, respectively. In conclusion, the combined use of geophysical methods in this study provided detailed subsurface images that were validated by excavation data.

ABSTRACTThe integrated use of remote sensing (RS) techniques, vertical magnetic gradient (VMG) and electrical resistivity tomography (ERT) measurements, and, in particular, combined analysis of 2D and 3D data, can provide a viable option for the identification of targets of interest at complicated archaeological sites. In this regard, a case study is Kom C at the archaeological site of Buto (Tell El Fara'in) in the northern Nile Delta (Egypt), where satellite data (Google Earth, Landsat 8 and OrbView‐3), VMG and ERT measurements were collected prior to site excavation. In this particular case, soil salinity in the buried structures, a lack of contrast in magnetic susceptibility and electrical resistivity, as well as the orientation, complex spatial distribution and overlapping of the architectural elements, all contributed to a number of anomalies that were difficult to interpret using only 2D results. Initially, the archaeological remains were identified as being made of mud‐brick based on land surface temperature (LST) estimated from thermal bands (Bands 10 and 11) in Landsat 8. Then, the high‐resolution satellite data, as well as the VMG and ERT (2D, quasi‐3D and full 3D resistivity models), were integrated to produce a comprehensive map of buried archaeological features. Excavations by Kafrelsheikh University in collaboration with the Ministry of Tourism and Antiquities recovered archaeological remains, including architectural elements that were perhaps used for official or administrative purposes or pottery‐making workshops during the Late Roman period (between the 4th and 7th century ce). The direct comparison of geophysical results to archaeological evidence from the excavation enabled a robust interpretation of geophysical anomalies visible in the horizontal resistivity depth slice and magnetic maps. As a whole, this case study highlights the value of combining satellite data with the analysis of 2D data and 3D views of geophysical surveys to better understand the real distribution of buried archaeological remains at similar complex sites.

The United Arab Emirates holds great historical importance, as evidenced by many archaeological sites, such as the Jebel Hafit Tombs and the Hili Archeological Park in Al Ain. At the western edge of Mutaredh Oasis, a major new archaeological site was discovered in 2023 during a construction project. Several important archeological features have been documented, including an earthen mosque and boundary walls, Iron Age irrigation systems, and a circular stone tomb dating to the Bronze Age. However, the eastern edge of the Mutaredh site has remained unexplored to date. Ground Penetrating Radar (GPR) has been proven to be a successful method in mapping archaeological remains. Accordingly, a high-resolution GPR survey was carried out to identify the continuity of the unearthed archeological elements and delineate new unexplored features. A comprehensive 3D model of buried archaeological features was constructed using the acquired high-resolution GPR data in the eastern part of the Mutaredh site. Several selected anomalies have been observed, similar to the uncovered features in the western part of the Mutaredh site and structures documented in other nearby archaeological sites. The geometry and extension of these anomalies have enabled the possible identification of a further two Bronze Age circular tombs, as well as the delineation of a system of water channels (falaj), and irrigation networks with tree pits from the Iron Age. Moreover, walls probably belonging to the Late Islamic Age are identified. These findings suggest that Mutaredh has been a site of intensive human activity from the Bronze Age through to the Late Islamic period. Given the density of identified anomalies, further significant features are anticipated to lie buried in the immediate surrounding areas, promising continued insights into the area’s rich archaeological heritage. The findings of this study may guide archaeologists to specific locations and assist in selecting the most appropriate excavation techniques for the verification stage.

Atomic archaeology? Using portable gamma surveying techniques to identify buried archaeological features

Archaeological evidence has demonstrated that the Bujang Valley is Malaysia's richest archaeological site and served as the primary coastal centre. A study in the Bujang Valley found monuments related to trading activities and others that functioned as a temple related to the Hindu-Buddhist period. The main purpose of this study was to resolve issues and problems arising from previous studies related to the Bujang Valley civilisation, particularly in terms of iron studies. Geophysics plays a vital role in assisting archaeologists to obtain excellent preliminary results before they proceed with excavation and digging works. Therefore, the 2-D resistivity and ground-penetrating radar (GPR) methods were conducted to locate and map the potential iron smelting site at Site B2 (SB2). Three main characteristics that can be observed on the surface are a mound area, exposed clay bricks and surface finds. Two-D resistivity showed the resistivity values of a possible buried structure, with values > 800 Ωm. Radargram profiles showed the highest amplitude, indicating the reflections uncovered in the location in certain survey lines. This paper presents the first summary of research on the metallurgical sites in the Bujang Valley, the most important site in Malaysia. Geophysical methods, which rely on a physical contrast between buried archaeological features and the properties of the surrounding subsoil, can assist archaeological investigations.

Abstract Several studies have suggested the potential value in applying gamma radiation surveys to support identification of buried archaeological features. However, the number of previous studies is very small and has yielded mixed results. The true efficacy of the technique is therefore unclear. Here, we report on an alternative survey method that uses Groundhog®, a portable gamma radiation system with spectrometric capability, to achieve high spatial density monitoring of archaeological sites. The system, which is used extensively in the nuclear industry, was used to carry out preliminary surveys at four different locations within the Silchester Roman Town. Targeting a site for which an extensive amount of archaeological data is available facilitated testing of the method on a range of known target types. Surveys were carried out along 1‐m transects at an approximate walking speed of 1 m per second, resulting in the capture of one radiation measurement per square metre. Total gamma radiation, recorded in counts per second, was presented in the form of surface radiation (contour) maps and compared against existing geophysical data. Total gamma counting consists of counting gamma rays, without energy discrimination, that are spontaneously emitted by the material under investigation. The obtained counts represent the total, or gross, gamma contribution from all radionuclides, both natural background series and anthropogenic. Radiation anomalies were identified in two of the four survey sites. These anomalies correlated with features present in the geophysical data and can be attributed to a Temenos wall bounding the temple complex and an infilled clay pit. Early results suggest that this may be a complementary technique to existing geophysical methods to aid characterization of archaeological sites. However, it is believed that data quality could be significantly improved by further increasing spatial resolution. This will be explored as part of future fieldwork.

In intensively cultivated landscapes, many archaeological remains are buried under the ploughed soil, and detection depends on crop proxies that express subsurface features. Traditionally these proxies have been documented in visible light as contrasting areas of crop development commonly known as cropmarks. However, it is recognised that reliance on the visible electromagnetic spectrum has inherent limitations on what can be documented, and multispectral and thermal sensors offer the potential to greatly improve our ability to detect buried archaeological features in agricultural fields. The need for this is pressing, as ongoing agricultural practices place many subsurface archaeological features increasingly under threat of destruction. The effective deployment of multispectral and thermal sensors, however, requires a better understanding of when they may be most effective in documenting archaeologically induced responses. This paper presents the first known use of the FLIR Vue Pro-R thermal imager and Red Edge-M for exploring crop response to archaeological features from two UAV surveys flown in May and June 2019 over a known archaeological site. These surveys provided multispectral imagery, which was used to create vegetation index (VI) maps, and thermal maps to assess their effectiveness in detecting crop responses in the temperate Scottish climate. These were visually and statistically analysed using a Mann Whitney test to compare temperature and reflectance values. While the study was compromised by unusually damp conditions which reduced the potential for cropmarking, the VIs (e.g., Normalised Difference Vegetation Index, NDVI) did show potential to detect general crop stress across the study site when they were statistically analysed. This demonstrates the need for further research using multitemporal data collection across case study sites to better understand the interactions of crop responses and sensors, and so define appropriate conditions for large-area data collection. Such a case study-led multitemporal survey approach is an ideal application for UAV-based documentation, especially when “perfect” conditions cannot be guaranteed.

Hadrian’s Villa is an ancient Roman archaeological site built over an ignimbritic tuff and characterized by abundant iron oxides, strong remnant magnetization, and elevated magnetic susceptibility. These properties account for the high-amplitude magnetic anomalies observed in this site and were used as a primary tool to detect deep archaeological features consisting of air-filled and soil-filled cavities of the tuff. An integrated magnetic, paleomagnetic, radar, and electric resistivity survey was performed in the Plutonium-Inferi sector of Hadrian’s Villa to outline a segment of the underground system of tunnels that link different zones of the villa. A preliminary paleomagnetic analysis of the bedrock unit and a high-resolution topographic survey by aerial photogrammetry allowed us to perform a computer-assisted modelling of the observed magnetic anomalies, with respect to the archaeological sources. The intrinsic ambiguity of this procedure was reduced through the analysis of ground penetrating radar and electric resistivity profiles, while a comprehensive picture of the buried archaeological features was built by integration of the magnetization model with radar amplitude maps. The final subsurface model of the Plutonium-Inferi complex shows that the observed anomalies are mostly due to the presence of tunnels, skylights, and a system of ditches excavated in the tuff.

Abstract One of the major problems in the forward modelling of magnetic anomalies is the assessment of a minimum level of acceptable accuracy in the fit between observed and theoretical anomalies. We present a new approach to the analysis and interpretation of archaeological magnetic anomalies, based on classical algorithms of forward modelling and a new technique of error assessment. This approach allows us to determine geometry, physical properties, and location of buried archaeological features, as well as the occurrence of fires or other historical events that may have affected the observed magnetic signal. Our method starts from the acquisition of total field data, usually in a regular grid arrangement, and proceeds through their reduction to archaeological magnetic anomalies. This reduction is performed subtracting from the observed total field data a polynomial representation of the regional field, on the basis of a rigorous criterion that tries to separate archaeological anomalies from geological (crustal) contributions. At the next step, a map of the maximum allowed misfit is built, which depends from the estimated uncertainty at each point of the magnetic anomaly field. This map specifies the maximum allowed deviation of theoretical anomalies from the observed values. The last step is the analysis of these anomalies through a new forward modelling tool, with the objective to reconstruct the three‐dimensional arrangement of buried features and possibly obtain some information about the history.

The archaeological site of Sagalassos is a very important settlement located in a magnificent mountain landscape, 7 km north from a village named Ağlasun (province of Burdur, south-west Turkey). Since 1990, the University of Leuven (Belgium) has carried out an interdisciplinary archaeological research program that studies >1000 years of uninterrupted human occupation in Sagalassos, concerning all historical aspects of daily life from architecture, to trade and its mechanisms and environmental conditions. The ancient Roman city is covered by layers of eroded soil that has preserved many secrets waiting to be revealed. A geophysical campaign was planned along the south facing terraces of the mountain slopes to highlight the structure of the city that remains covered in soil. Site conditions (high slope, high grass, several obstacles) and the need to investigate to depths greater than 20 m influenced the choice of geophysical methods; we chose to use both passive and active electrical resistivity tomography. Three different areas, labelled Area 1, Area 2 and Area 3, were investigated, with results revealing information about the location, depth, size and extent of buried archaeological features. Of particular interest is the presence of: (i) a deep depression in Area 1, thought to be a clay quarry; (ii) a number of tombs related to the Byzantine period in Area 2; and (iii) defensive walls in Area 3.

ABSTRACTA ground‐penetrating radar survey was carried out at The Great Temple Mound (Mound A), Ocmulgee National Monument, Georgia, USA to determine the location of buried archaeological features. Mound A is the largest pre‐historic mound at the site and its function remains unclear. High quality data and sufficient spatial sampling with a 500‐MHz centre frequency antenna facilitated the generation of two‐dimensional profiles and amplitude depth slices. The analyses presented here describe a processing sequence used to improve the image fidelity and the visualization of the remains of a relict archaeological excavation unit. Additionally, we employ depth slice overlay analysis for enhanced visualization of this feature. The results demonstrate a new processing methodology that helps in delineating the lateral extent of the excavation and its evolution. The results also highlight the implementation of a new visualization strategy in GPR surveys aimed towards detecting graves, burial tombs, and other rectilinear or cubic features. We conclude that even with excellent GPR imaging, there may be significant positioning errors in defining the boundaries of buried features.

Kamarina, located in southern Sicily (Italy), was an important Greek colony since its foundation in the sixth century BC. Archaeological excavations, carried out since the twentieth century, uncovered only limited portions of the site so far. Despite the importance of the Greek colony, the presence of remarkable buildings that archaeologists expected to bring to light has not found fully correspondence in the archaeological excavations. Consequently, the integrated geophysical prospection carried out in the study area is aimed to support and address the future archaeological investigations. After the photographic and thermographic survey obtained by an unmanned aerial vehicle, we performed a systematic survey through ground magnetic and GPR methods over an area of 6200 m2. The acquisition procedures have been optimized in order to get the best results combining high resolution and elevated speed of acquisition. The results derived from the three geophysical techniques have been conveniently combined by means of a cluster analysis, allowing us to clearly identify a series of buried archaeological features. Because of their geometrical characteristics, often in good agreement with the spatial arrangement of the archaeological remains at the surface, these buried archaeological features can be interpreted as roads, walls, or buildings foundations in which the various construction phases of the city can be clearly recognized. The integrated approach has proven to be essential for a robust interpretation of the archaeogeophysical investigation.

A linear 3-D transformation that can be used for the enhancement of crop marks related to buried archaeological features is developed and presented in this article. The methodology is based on three steps: (1) recalculation of the ground narrowband spectroradiometric measurements to the multispectral Landsat 5 Thematic Mapper (TM) sensor, based on the relative response filter of the sensor, (2) application of principal component analysis (PCA) transformation in order to determine the initial axes used for the orthogonal transformation, followed by (3) a 3-D rotation of the PCA axes. The linear coefficients of the transformation were retrieved and adjusted to different phenological stages of the crops. The transformation was successfully evaluated using both in situ measurements and Landsat 5 TM images in two different archaeological case studies. The proposed transformation tends to enhance archaeological signatures better than other established vegetation indices or algorithms, while the methodology can be expanded to any other multispectral satellite images using only the visible and very near-infrared part of the spectrum.

Unveiling the prehistoric landscape at Stonehenge through multi-receiver EMI

This paper aims to introduce new linear orthogonal equations for different satellite data derived from QuickBird; IKONOS; WorldView-2; GeoEye-1, ASTER; Landsat 4 TM and Landsat 7 ETM+ sensors, in order to enhance the exposure of crop marks. The latest are of significant value for the detection of buried archaeological features using remote sensing techniques. The proposed transformations, re-projects the initial VNIR bands of the satellite image, into a new 3D coordinate system where the first component is the so called “crop mark”, the second component “vegetation” and the third component “soil”. For the purpose of this study, a large ground spectral signature database has been explored and analyzed separately for each different satellite image. The narrow band reflectance has been re-calculated using the Relative Spectral Response filters of each sensor, and then a PCA analysis was carried out. Subsequently, the first three PCA components were rotated in order to enhance the detection of crop marks. Finally, all proposed transformations have been successfully evaluated in different existing archaeological sites and some interesting crop marks have been exposed.

Integration of geophysical surveys, ground hyperspectral measurements, aerial and satellite imagery for archaeological prospection of prehistoric sites: the case study of Vésztő-Mágor Tell, Hungary

ABSTRACTResults of electrical resistivity surveying and pseudo‐three‐dimensional tomographic imaging at the 15 ha Pre‐Hispanic archaeological site of Sitio Drago, Isla Colon, Bocas del Toro province, Panama are presented. The site was occupied between ad 690–1410 and represents the largest known nucleated settlement in the province. A low mound in the centre of the site was selected for intensive electrical surveying in order to locate buried archaeological features. A series of surveys were conducted, including electrical resistivity mapping and pseudo‐three‐dimensional tomographic imaging. The results revealed a group of resistivity anomalies associated with buried archaeological features. Based on these results, archaeological excavations were targeted that uncovered a cluster of coral slab structures, each containing human remains. Copyright © 2012 John Wiley & Sons, Ltd.

Archaeological magnetometry in an Arctic setting: a case study from Maguse Lake, Nunavut

Abstract Geophysical investigations through mobile multi‐electrode systems, such as the automatic resistivity profiling (ARP) method, can increase the size of the surveyed areas without jeopardizing the spatial resolution of the survey. The representation of the apparent resistivity data in maps corresponding to the different measuring dipoles is sufficient in most routine applications for outlining the buried archaeological structures. In specific cases where a more quantitative interpretation of the apparent resistivity data is demanded, a three‐dimensional resistivity inversion can provide the necessary tool for this purpose.This work investigates the possibilities and limitations of the three‐dimensional resistivity inversion in processing the ARP data. A three‐dimensional finite element smoothness‐constrained inversion algorithm was used. The active constraint balancing (ACB) method was also applied in order to enhance the stability and the resolving power of the inversion procedure.Resistivity models that are commonly encountered in archaeological exploration were used to generate synthetic apparent resistivity data using a three‐dimensional finite element forward modelling program. Inversion of the synthetic data showed that the maximum investigation depth of the ARP method is comparable to the length of the larger receiving dipole and cannot exceed the 2–2.5 m for the particular ARP device tested in this work. Archaeological structures buried within this depth range can be effectively mapped, while the resolution of the subsurface structures is related to the data acquisition parameters. The inversion algorithm was also used to reconstruct the three‐dimensional resistivity distribution from the ARP data set collected from the Andilly archaeological site in France. The results effectively showed that the three‐dimensional inversion can act as a complementary tool in acquiring a more quantitative interpretation model of the buried archaeological features. Copyright © 2009 John Wiley & Sons, Ltd.

Three different surveys have been performed at Monbaron in the Champagne Berrichonne region to the southof Levroux (Indre, France). The first survey (1992), using the square array resistivity method, aimed to identify the presence of buried archaeological features, mainly ditches. The second one (1996), corresponding to a test of a new multi-depth instrument, aimed both to assess its abilities and to increase the extent of the surveyed area. The preservation of buried features, observed by co...