Roman Archaeological Site Research Articles

Analytical characterization of historical mortars from the Roman villa of Frielas (Loures, Portugal)

The analytical characterization of mortar samples from the Roman archaeological site of Frielas, located in Lisbon, Portugal; was carried out by means of X-diffraction (XRD), thermogravimetry (TGA-DTG), optical microscopy and scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS), acid attack and granulometric analysis. A total of eighteen mortar samples were collected from the different structures of the villa with different functional uses (render, filler, and floor). The results showed a similar composition of binder, while differences in aggregates allowed to establish several groups. Results were discussed as evidence of manufacturing techniques, production technologies, and provenance of possible raw materials. There was no prominent variation that can suggest a different chronology between the group of samples. Though, it is assumed that there might be some renovation, restoration, or partial rebuilding that occurred in the same period. In terms of production technology, proportions ruled by Vitruvius were not followed.

Analysis of pigments and mortars from the wall paintings of the Roman archaeological site of Las Dunas (San Pedro de Alcántara, Malaga S Spain)

This study aims to describe the composition, texture, and arrangement of mortars and pictorial layers from a newly excavated Roman archaeological site in the province of Baetica, southern Spain. Representative fragments with well-preserved pictorial layers were analyzed using optical imaging, spectrophotometry, Scanning Electron Microscopy with Energy-Dispersive Spectroscopy (SEM-EDS) mapping, and X-ray diffraction. The results reveal similarities to other well-studied Roman archaeological sites, particularly in the use of mixtures of natural (hematite, goethite, aragonite, phyllosilicates, and quartz) and synthetic minerals (cuprorivaite) used in classical Roman pigments. However, the mortar from the investigated site shows a distinctive use of ferromagnesian silicates (olivine and pyroxenes from local ultramafic rocks) as aggregate material, making this site unique among all Roman provinces. Additionally, the common occurrence of Mg in the binder of the mortars under the form of brucite, hydromagnesite and magnesium silicate hydrates, indicates the use of a magnesian (dolomitic) lime that, according to the chemical analyses, was obtained by adding up to 15 wt% of powdered dolomitic marbles from nearby Roman quarries to the limestone. We speculate that this addition might be intended to improve the workability and mechanical resistances of the mortar in combination with the abundant ferromagnesian silicates used as aggregates, some of them showing chemically reactive rims in contact with the binder. In conclusion, this study provides further evidence of the advanced knowledge and skills achieved by Roman craftsmen who were able to adapt traditional recipes to suit local resources, obtaining materials of excellent quality and durability.

High resolution multi-methodological geophysical investigations to enhance the knowledge of Tusculum archaeological site (Roma, Italy)

To better understand the location and help in the conservation of buried structures in the ancient site of Tusculum, in Central Italy, archaeological and multi-methodological geophysical studies were developed in the recent last years. These studies included geophysical surveys, which were combined with topographical survey and direct archaeological excavations. Tusculum is one of the largest Roman archaeological sites in the Alban Hills, located in the Latium region (Italy), about 25 km South-East of Rome. This settlement was inhabited since pre-Roman times, up to the middle ages. The objective of the Tusculum Project is to verify the town-planning of Tusculum and to obtain information about the location, shape, depth and size of the hypothesised buried buildings. With these aims, multi-methodological geophysical surveys have been carried out in the time range 2016–2019 to locate the archaeological remains in different portions of the studied area and to verify the orientation of the underground aqueduct system. GPR and gradiometric surveys were carried out to investigate the archaeological remains, while ERT surveys, were employed to find evidence of undiscovered parts of the underground aqueduct system. These results, along with geological studies and historic evidence, are being examined by archaeologist to understand the limits of the town and how water was supplied to such a large, populated settlement. The obtained results show very good correspondence between the buried architecture, the geophysical anomalies and the archaeological excavations. A number of unexpected buried buildings were discovered, which were excavated in 2017 and 2018, which showed remains of buried public thermal bath and a large church with surrounding funerary area built in the Middle Ages.

Quick bathymetry mapping of a Roman archaeological site using RTK UAS-based photogrammetry

Recent technological advances are leading numerous researchers and professional users to the adoption of photogrammetric products for a wide range of geoscientific applications. Especially, drone-based Structure-from-Motion (SfM) photogrammetry is often applied as a high-resolution topographic modelling technique with advantages in terms of time and cost when compared to traditional surveying approaches. The aim of this work, carried out within the GeoArchaeo Sites Project, is to investigate the adaptability of drone-based surveys, even with a targetless approach, and to estimate bathymetrical accuracies in shallow waters. The approach was applied on an underwater site to show the potential for the digitalization and monitoring of an archaeological coastal geosystem in central Italy. Specifically, this work has compared the photogrammetric surveying capability of two drones including a Phantom 4 RTK (‘P4RTK’) and a low-cost Mavic Mini 2 (‘MM2’) and an Olympus TG-6 (underwater camera) for a site submerged with a maximum depth of ∼1.6 m. The assessment of the drone SfM-based products was performed through area-based and point-wise comparisons. Specifically, the area-based were assessed through an underwater photogrammetric survey obtained by acquiring images by an operator snorkeling along a portion of the site of interest. The point-wise comparison was performed using data acquired with a Global Navigation Satellite System (GNSS). This study demonstrates that coupling SfM-photogrammetry and UAS-based surveys have potential to define submerged topography. In particular, the imagery acquired with the P4RTK survey can produce dense 3D models of the underwater surface with high resolution (about 0.02 m) and bathymetric measurements with a vertical accuracy ranging between 0.06 and 0.29 m for the area-based and point-wise analysis, respectively. Thus, the approach adopted and tested involving the use of a P4RTK has the potential to reduce constraints and limitations in terms of GCPs distribution and measurement. Also, with such an approach the need for qualified operators for underwater photogrammetric workflow can be avoided.

New challenges in archaeopalynology: Pollen analysis on Roman bivalve shells from south-western Europe and North Africa

The European flat oyster (Ostrea edulis) is a native species that was consumed as a luxurious product by the Romans. In the Strait of Gibraltar area, between southwest Iberia and North Africa, numerous oyster shells have been found in Roman archaeological sites located in both, the Atlantic Ocean and the Mediterranean Sea. The origin of these oysters is unknown, as so if they were farmed or harvested in the wild and/or even imported for consumption. This study presents the results of pollen analysis of oyster shells from six archaeological sites in the Strait of Gibraltar area dated between the 1st and 6th centuries AD. This is the first time that such research is undertaken in the Iberian Peninsula and North Africa; the second worldwide for a discipline rarely known until now: conchopalynology. Our study suggests that differences observed in pollen spectra could be used to identify the origin of the consumed specimens, i.e. where they were grown or harvested, discriminating whether oyster shells originated from the Mediterranean Sea or the Atlantic Ocean coastline.

Geomagnetic and FDEM Methods in the Roman Archaeological Site of Bocca Delle Menate (Comacchio, Italy)

The increasing use of geophysical investigations for archaeological purposes is now provided also by Italian reforms about preventive archaeology. They allow not only the discovery or the spatial definition of possible buried archaeological evidence, but they are also able to define the state of preservation of ancient structures. The Bocca delle Menate archaeological site is in Comacchio village territory, situated in Ferrara provence (Emilia Romagna region, Italy). The archeological site provides important evidence of the Roman presence in the Po Delta (Italy). The Roman villa was excavated between 1958 and 1959, during the reclaiming works in the Mezzano Valley (Comacchio, Ferrara). An archaeological preliminary survey and a geophysical field trip using Geomagnetic and Frequency Domain Electromagnetic Methods were carried out, following the aim to identify the planimetry of the villa previously excavated and eventually newly discovered archaeological remains. The geomagnetic results detected the archaeological buried structures, even if the original disposition of them is not completely highlighted. The electromagnetic method was able to depict the geological and geomorphological background surrounding the Roman villa. The obtained results highlighted that the applied geophysical methods are excellent tools for the preservation, protection, and monitoring of archaeological heritage previously excavated, adding to their already known importance as best tools for new archaeological buried remains detections.

Roman coins at the edge of the Negev: characterisation of copper alloy artefacts and soil from Rakafot 54 (Beer Sheva, Israel)

The research presented in this paper focused on the preliminary non- and semi-destructive analysis of copper alloys, corrosion, and soil components from a Roman archaeological site in Israel. Investigations using portable X-ray fluorescence, X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy as well as micromorphological analyses were carried out to gain a better understanding of the corrosion processes affecting the copper alloy artefacts, by characterising the alloy composition, soil environments, and corrosion products. Preliminary results indicate that the artefacts consist of copper-lead-tin alloys, covered by copper hydroxy-chlorides and lead sulphate phases with slight variations in their crystallisation. The multi-analytical approach revealed the presence of quartz, calcite, gypsum and feldspars in the sediments, while thin sections more specifically indicate loess soils with local micro-environments

Socialization of Immovable Roman Archaeological Sites in Bulgaria

The archaeological cultural heritage and its inclusion in projects for the creation of tourist attractions, tourist products and marketing of the destinations are among the leading priorities in the field of tourism in Bulgaria. In this sense, the aim of the current paper is a review and analysis of the socialization of the immovable archaeological sites from the Roman period in the country. The socialization is considered from several aspects - exposure, preservation, presentation, provided services and organized events, accessibility, technical and ancillary infrastructure, advertisement. In each of them, the applied basic techniques and methods are studied and illustrated with specific examples of sites with national importance from the Roman period. In conclusion, more important problems and challenges related to the socialization are presented. Their resolution is of importance for the preservation of the immovable archaeological monuments and the sustainable development of tourism, based on archaeological heritage.

Playing finger cymbals in the Roman Empire: an iconographic study

Abstract Finger cymbals, played with one pair in each hand like castanets, are iconic of the Middle Eastern ‘belly’ dance, which has been represented in numerous pictorial works and photographs since the 18th century. Middle Eastern dancers show that it is possible to dance while using two small cymbals in each hand, attached to two different fingers with straps from the cymbals’ holes. Starting from the observation that many such small cymbals have been found in Roman archaeological sites, this article asks whether Roman dancers played these small cymbals like Middle Eastern dancers do today. The question is complex, because Roman dancers were able to play small cymbals in other ways, such as holding just one in each hand, or inserting them into cymbal tongs. This article presents a typological and functional study of small metal cymbals attached to fingers in Roman iconography. Three examples are considered: a mosaic from the Roman city of Augusta Traiana (now Stara Zagora) in Bulgaria, and two stone reliefs, one from Orolaunum (now Arlon) in Belgium and another from the Podocataro Palace in Rome, dated from the 2nd to the 4th centuries ce. These remains testify to the use of fingers cymbals, two in each hand, attached directly to two different fingers, by dancers from the Roman Empire.

Metalwork from Roman doors – examples in Bosnia and Herzegovina

Almost every Roman site, particularly those where sizeable buildings have been found, also yield the remains of security systems – pieces of locks, hinges, keys and so forth that served to lock and secure the buildings as a whole or separate rooms, or chests and caskets. This is also true of sites in present-day Bosnia and Herzegovina, where such material has been found at various Roman archaeological sites. Most such objects are kept in the National Museum of Bosnia and Herzegovina, but some important artefacts are also located in the Franciscan Monastery in Visoko, the Museums in Doboj, Travnik, Tuzla, Zenica and Bijeljina, and other museum institutions and collections.

Structural Assessment of Ancient Masonry Structures: An Experimental Investigation on Rubble Stone Masonry

ABSTRACT Non-destructive investigation procedures are appropriate approaches for the qualitative mechanical assessment of heritage masonry structures. This study aims to contribute to the knowledge of one of the most common ancient masonry typologies, particularly in Roman archaeological sites, the rubble stone masonry, that is the ancient opus incertum, with an extensive experimental program carried out in the archaeological site of Pompeii. The research focused on archaeological masonry structures with different states of preservation and with or without modern interventions. A non-destructive investigation procedure was carried out including detailed geometrical and material surveys, visual inspections and an extensive program of sonic pulse velocity tests, with a total of 1965 acquired velocities. The paper describes the adopted investigation protocol and detailed analysis and discusses the experimental outcomes. Comparisons with available literature data concerning different masonry typologies at the Pompeii site are also presented. Furthermore, the results of the non-destructive investigation have been compared with available mechanical information from destructive and non-destructive tests performed by the authors on Pompeii-like masonry panels. The unique set of data collected may represent a sound tool for the estimation of the mechanical parameters of the ancient masonry structures, which is a crucial step for the definition of preservation actions.

Optimised Extraction of Archaeological Features from Full 3-D GPR Data

The use of non-invasive methodologies is becoming essential for archaeological research, and ground penetrating radar is one of the most important techniques to obtain high resolution information. In this paper we present the analysis of a full 3-D GPR dataset integrated with a high-resolution photogrammetric survey acquired in a Roman archaeological site located in Aquileia (Northeast Italy) within the partially excavated area known as “Fondo Pasqualis”. We evaluated the importance of dense and accurate data collection and of processing of the GPR signal for characterization of the archaeological features. We further discuss the parametrization and the applicability of GPR attributes, in particular amplitude-based and coherence attributes, to better identify and characterise the archaeological buried targets. Furthermore, autopicking procedures for isosurfaces mapping were critically evaluated with the objective of detecting complex structures. The final interpretation of all the GPR features, with the support of digital terrain modelling and orthophotos from unmanned aerial vehicles, guided the archaeologists to open and excavate newly selected areas, which revealed interesting structures and contributed to the understanding of the historical events that characterized the Aquileia city.

Multi-analytical identification of a painting workshop at the Roman archaeological site of Bilbilis (Saragossa, Spain)

In this work, we studied wall painting fragments from the exedra in Domus 1 and tablinum in the House of the Lararium in Bilbilis, an ancient Roman town in the Spanish province of Saragossa, in order to find whether the two paintings were produced by the same artisan workshop and to identify the painting technique used. For this purpose, we examined the paint and mortar layers of the fragments by using various semi-destructive instrumental techniques including X-ray diffraction (XRD), X-ray fluorescence (XRF) and Raman spectroscopies, and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM-EDS). The fragments used were representative of the colours in each paint, which included black, yellow, green, burgundy, beige and orange. Raman spectroscopy in combination with XRF analyses allowed the chemical composition of each pigment to be unequivocally established. All pigments (carbon, yellow ochre, a glauconite–Egyptian blue mixture, hematite, aragonite and red lead) were typically used in Hispania. Based on the Raman and XRD results, the mortars were obtained in the traditional manner by mixing sand and lime.

The application protocol impacts the effectiveness of biocides against lichens

This work analyzed the influence of different application protocols on the efficacy of two biocides against the foliose lichen Xanthoparmelia tinctina on the sandstones of the Roman Archaeological site of Luni (Italy). The hypotheses that (a) biocide application tools (brush vs. poultice), (b) pre-treatment hydration, and (c) post-treatment washing may affect devitalization success were verified by monitoring chlorophyll a fluorescence of thalli, both in situ and in laboratory conditions. The hypothesis that (d) stone substrate may act as reservoir for later biocide release under repeated cycles of wetting and drying was also assayed. Analyses confirmed the importance of the application tool, with cellulose poultice being more effective than brush. Hydration influenced the biocide absorption by thalli. Moreover it modulated the metabolic activity and susceptibility to the available toxic compound, hindering lichens from entering a dormant state to tolerate stress. Depending on the preparation solvent (water vs. white spirit), the biocide application benefited from pre-treatment hydration and/or a post-treatment washing. Lastly, we showed that different sandstones variously adsorb the biocides and potentially contribute as a reservoir for their long-term release at low concentrations during successive hydration events.

New high precision full-vector archaeomagnetic data from a roman kiln in Mérida (Spain)

This study presents new high precision age and full-vector archaeomagnetic data from a kiln excavated in the Roman archaeological site of Mitreo's house (Mérida, Badajoz, Spain). The age of the kiln was obtained by the stratigraphic method and by the ceramological study of the italic and sigillata pottery found with a very precise age date of 55 ± 15 years AD. Rock-magnetic experiments pointed towards magnetite as the main carrier of remanence and highly reversible thermomagnetic curves suggested that the studied samples were suitable for archaeoeointensity determinations.Paleomagnetic experiments including thermal and stepwise alternating field demagnetization yielded the following mean direction for the kiln: declination D = 0.6°; inclination I = 54.0°; (k = 481; α95 = 2.5°). Archaeointensityexperiments with the Thellier – Coe protocol on 28 samples yielded successful determinations in 27 cases. Anisotropy factors between 0.90 and 1.04 were obtained from anisotropy of thermoremanent magnetization (ATRM) experiments. A mean anisotropy-corrected archaeointensity value F = 56.3 ± 5.5 μT was obtained.The geomagnetic model SHA.DIF.14 k was used for an archaeomagnetic dating yielding a chronological interval between 40 BCE and 150 CE. This low age resolution when compared with the pottery-based age data is related to the behavior of the geomagnetic field in the Iberian Peninsula during the Roman period, which does not allow to differentiate well between results corresponding to those centuries. However, it is also related to the fact that the Iberian archaeomagnetic dataset in the analysed time range is highly scattered. A high quality full-vector data with a very precise age have been obtained which contribute to improve the Iberian secular variation curve and geomagnetic databases.

Multidrum Stone Columns at the Pompeii Archaeological Site: Analysis of Geometrical Properties and State of Preservation

The seismic vulnerability of ancient free-standing multidrum stone columns is an important issue for the preservation of Greek and Roman archaeological sites. Such elements show a complex and highly non-linear dynamic behavior, requiring specific and sophisticated structural analysis. Different numerical studies on the dynamic behavior of ancient multidrum stone columns found that their seismic response is sensitive to their geometrical parameters, as well as to the material elastic properties, the kinetic coefficient of friction and the amplitude and frequency of the seismic action. Therefore, in the present research, a detailed survey of free-standing multidrum stone columns representative of a wide range of elements at the Pompeii Archaeological site was developed to provide a primary evaluation of the seismic vulnerability of such elements based on their geometrical properties. The study focuses on 103 multidrum grey-tuff columns, from four areas at the site: tetrastyle atrium of Casa del Fauno at Regio VI and Quadriportico dei Teatri, Foro Triangolare and Palestra Sannitica at Regio VIII. Grey tuff was a typically locally sourced natural stone, used as a building material in ancient Pompeii. The research areas included both private (Casa del Fauno) and public buildings (Quadriportico dei Teatri, Foro Triangolare and Palestra Sannitica). The mean overall geometrical properties affecting the seismic behavior of the columns in each research area and the discussion of the collected results are herein presented.

Particulate dry deposition on sheltered archaeological remains: Considerations based on Complutum, a Roman site in Spain

Abstract Dry deposition of particulate matter (PM) onto archaeological surfaces is one of the main causes of decay since it implies both visual changes and chemical weathering. In the case of sheltered archaeological sites, it has been verified that particulate matter highly accumulates on the remains. However, the great majority of studies focuses on outdoor monuments or indoor museum objects. Dust collectors in the form of shelf-adhesive film patches were exposed for 1 and 3 months inside and outside the two shelters of Complutum, a Roman archaeological site (I–IV century A.D.) in central Spain. This study has provided a visual and chemical characterisation of the deposits by X-Ray Diffraction and Scanning Electron Microscopy equipped with Energy-Dispersive X-Ray spectroscopy (XRD and SEM). In addition, the amount of deposition has been assessed by gravimetric studies and by analysing the light transmittance of the dust collectors. Therefore, the main sources of the PM found on the remains, most affected areas within the site, and the consequences of dark particle deposition on the archaeological surfaces have been determined. It has been corroborated that PM accumulates inside the shelters in a great extent, and the original construction materials of the site contributes enormously to the type of deposition. In addition, the shelters reduce the access of the black particles which are potentially reactive (PM10) but they do not avoid the visual effects of particulate dry deposition on the horizontal remains.

SEISMIC VULNERABILITY ASSESSMENT OF THE TRIUMPHAL ARCH OF CARACALLA IN VOLUBILIS (MOROCCO): PAST EVENTS AND PROVISIONS FOR THE FUTURE

Abstract. The triumphal arch of Caracalla in the Roman archaeological site of Volubilis dates back to 216 AD. It was built in a strategic position at the intersection of the main roads leading to the Forum, the decumanus maximus to the east and the roads from Porte à trios baies to the west, that almost certainly was the main gate to the city. The current arrangement of the monument is the result of a restoration intervention carried out in the 1930s by French restorers. Some ancient photos witness that the monument was just a ruin in 1915, when Chatelain carried out the former archaeological excavations and, as a consequence, that it was totally rebuilt. In fact, the monument suffered wide damages provoked by the 1755 Lisbon earthquake, that affected also Morocco, which almost completely destroyed it. By means of the drawings made by the travelers Henry Boyde and John Windus, that retraced the monument thirty years before the earthquake, the original configuration of the monument can be observed and the timeline of events can be reconstructed. In this paper, the timeline of the seismic events that affected the triumphal arch is reconstructed and investigated by means of a structural analysis based on a rigid-block model. Finally, with the purpose of preventing future damage, the seismic vulnerability level of the construction is assessed with reference to its current configuration.

The performance of shelters for the conservation of archaeological sites in dry and warm climates: the case of Complutum

Excavated archaeological sites are frequently exposed to damaging environmental conditions, which could lead to rapid decay especially for vulnerable heritage such as mosaics. One of the most common solutions is the construction of shelters; however, some may not behave as expected, either because they do not protect adequately or induce decay. An environmental monitoring programme was undertaken inside and outside the two types of shelters at the Roman archaeological site of Complutum (Alcala de Henares, Spain) from May to September in 2018 and 2019. Hourly temperature and relative humidity readings collected by data loggers, together with rainfall data from a local meteorological station, have been comparatively assessed to better understand the consequences of sheltering in dry and warm areas. The results indicate that both shelters are avoiding further decay by keeping a more stable environment in relation to outside, although the more enclosed structure would be the most suitable one.

Comparative Performance Evaluation of the Shelters at Complutum, a Roman Archaeological Site in Spain

ABSTRACT The Roman city of Complutum (Alcala de Henares, Spain) conserves archaeological remains declared of cultural interest at an international level. The site presents two areas which are currently covered, the House of Hippolytus and the House of the Griffins, both with exceptional decorative programmes. Shelters are commonly considered the most suitable preventive conservation option for exposed archaeological sites, as they are able to reduce the impact of direct sunlight and rainfall. However, shelters may not fully protect a site and active decay has been often documented on covered remains. An extensive monitoring programme based on temperature, relative humidity, and light readings inside and outside the shelters has been undertaken over the course of a year (2018–2019) to evaluate the suitability of sheltering and the performance of the two types of covers from the point of view of the preservation of the remains.