Optimal sidescan sonar and subbottom profiler surveying of ancient wrecks: The ‘Fiskardo’ wreck, Kefallinia Island, Ionian Sea Publication date: January 2020 Source: Journal of Archaeological Science, Volume 113 Author(s): George Ferentinos, Elias Fakiris, Dimitrios Christodoulou, Maria Geraga, Xenophontas Dimas, Nikos Georgiou, Stavroula Kordella, George Papatheodorou, Michalis Prevenios, Makis Sotiropoulos Abstract Marine geophysical data collected during an underwater natural and cultural heritage assessment survey along the coastal zone of Kefallinia Island in the Ionian Sea, Greece, showed among other seafloor features, the presence of a Roman shipwreck and its amphorae cargo on the seafloor. The study and analysis of the collected data demonstrated that: (i) sidescan sonar and chirp sub-bottom profiling systems, can successfully detect ancient shipwrecks and their amphorae cargo on the seafloor, (ii) the use of objective computer vision techniques in processing sidescan sonar seafloor images, is a valuable tool for the separation of potential ancient shipwreck targets from other seafloor features with similar acoustic signatures. Furthermore, a guideline for the data acquisition parameters that should be used to obtain optimal seafloor sonar images to maximize the separation of potential shipwreck targets from other seafloor features, is provided. The underwater sonar remote sensing techniques may also provide adequate indication regarding the amphorae hull stowage and its vulnerability to human activity in the area. The shipwreck is dated between 1st century BC and 1st century AD and is one of the largest found so far in the Mediterranean Sea, for that period. It is estimated that it was carrying about 6,000 amphorae. The amphorae cargo, visible on the seafloor, is in very good state of preservation and the shipwreck has the potential to yield a wealth of information about the shipping routes, trading, amphorae hull stowage and ship construction during the relevant period and is therefore considered to be of significant archaeological importance.

Metal procurement, artefact manufacture and the use of imported tin bronze in Middle Bronze Age Cyprus Publication date: January 2020 Source: Journal of Archaeological Science, Volume 113 Author(s): Andreas Charalambous, Jennifer M. Webb Abstract Four hundred and fifteen Middle Bronze Age metal artefacts from Lapithos in Cyprus were examined using a portable ED-XRF analyser (pXRF). The results show a higher than expected presence of non-local tin and a small number of leaded bronzes and copper-zinc alloys. A more detailed analysis suggests the use of particular alloys for some artefact types, most notably high-arsenic and high-tin bronze for plain pins and toggle pins, as well as recycling and mixing practices not previously considered for this period on Cyprus. It would appear that Lapithos was engaged in the production of metal artefacts and that imported tin bronze and high arsenic copper ores from the Limassol Forest region, on the other side of the island, were available to local metalsmiths in significant quantities. Lapithos' location on the north coast, the sheer quantity of metal found at this site and the presence of imports also suggest that it was involved in the maritime metals trade which linked southeast Anatolia to the Aegean and the Cyclades in the first half of the 2nd Millennium BC.

Golden artefacts, resin figurines, body adhesives and tomb sediments from the pre-Columbian burial site El Caño (Gran Coclé, Panamá): Tracing organic contents using molecular archaeometry Publication date: January 2020 Source: Journal of Archaeological Science, Volume 113 Author(s): Joeri Kaal, María Martín Seijo, César Oliveira, Ewa Wagner-Wysiecka, Victoria E. McCoy, Mónica M. Solórzano Kraemer, Alexander Kerner, Philip Wenig, Carlos Mayo, Julia Mayo Abstract This research aimed to determine the origin of organic residues from funerary contexts in the El Caño settlement (Gran Coclé area, Panamá, Central America) by means of multiple molecular probing techniques (GC-MS of organic solvent extracts and pyrolysis-GC-MS, THM-GC-MS and FTIR of solid samples). The samples include particles of precious resin figurines, fillings of golden objects, tomb sediments, plant exudates from extant plants (reference collection) and other reference materials (amber). The labdane diterpene fingerprints (eperuic, iso-ozic, copalic and kolavenic acids and derivatives) of the resin figurines, a resinous bead and several other samples, suggest that they were composed primarily of Hymenaea resin. Besides traditional interpretation approaches (visual comparison of chromatograms and relative proportions data), we used a novel OpenChrom® application that resolves complex pyrolysis chromatograms by screening data from archaeological samples for marker products defined on the basis of a reference collection (ChromIdent). ChromIdent confirmed the Hymenaea origin of many samples and also Burseraceae resin was identified in some samples, which is present as a minor ingredient in resin figurines (indicative of mixing practices) and as the dominant resin in tomb sediment that had been in contact with the corpses (indicating balsaming practices). The degree of polymerization of the Hymenaea resin was higher than for extant resin but diagenetic alteration (especially condensation of cyclic moieties) was much smaller than for amber, implying that the manufacturers used resin (or copal), not amber. These results were confirmed by FTIR, which allowed identification of non-fossil Hymenaea resin as the main constituent of one of the resin figurines. Several golden object infillings contained wax derivatives, probably beeswax, accompanied by various types of plant resin, which may well indicate the use of meliponines' cerumen for manufacturing (lost-wax casting). The findings highlight the potential of complementary molecular techniques to resolve questions on materials and manufacturing of archaeological artefacts, and the need for cross-comparison of molecular and ethnographic information in the study of archaeobotanical remains and the processes involved in their management.

Challenges in sample processing within radiocarbon dating and their impact in 14C-dates-as-data studies Publication date: January 2020 Source: Journal of Archaeological Science, Volume 113 Author(s): Lorena Becerra-Valdivia, Rodrigo Leal-Cervantes, Rachel Wood, Thomas Higham Abstract For decades, researchers have employed sets of radiocarbon dates to reconstruct trends in ancient human populations. The overarching assumption in this analysis is that the frequency of dates is proportional to the magnitude of past human activity. Thus, the distribution of summed or otherwise summarized dates is used to extrapolate population density and mobility patterns. There are, however, a number of underlying assumptions associated with this analysis that workers address to varying degrees and which, if false and not critically accounted for, will introduce bias, misrepresent the magnitude of activity, and ultimately prove misleading in archaeological interpretations. In this regard, research has so far mainly focused on correcting for the effects of time-dependent degradation of archaeological sites and constituent materials, calibration irregularities, and the efficacy of the statistical methods used. Assumptions directly related to sample processing in radiocarbon dating, however, are less discussed in ‘14C-dates-as-data’ analyses. It is, for example, assumed that all carbonaceous materials will yield sufficient, endogenous carbon for radiocarbon measurement. Yet sample failure in radiocarbon dating is common and contingent on, largely, deterministic factors such as post-depositional environment. Sets of radiocarbon dates analyzed, therefore, represent successful measurements independent of reliability. In this work, we discuss the biases introduced by challenges in radiocarbon processing and their impact on 14C-dates-as-data studies.

Technological and behavioural complexity in expedient industries: The importance of use-wear analysis for understanding flake assemblages Publication date: December 2019 Source: Journal of Archaeological Science, Volume 112 Author(s): Riczar Fuentes, Rintaro Ono, Naoki Nakajima, Hiroe Nishizawa, Joko Siswanto, Nasrullah Aziz, Sriwigati, Harry Octavianus Sofian, Tatiana Miranda, Alfred Pawlik Abstract Expedient lithic technology has been described as unchanging and without or very limited presence of formal tool types. However, this premise seems to limit the discussion on technological and behavioural complexity when studying amorphous flake industries. To address this issue, we employed multi-stage use-wear analysis to identify features that are not detectable through macroscopic approach. Our analysis of chert tools from Leang Sarru, North Sulawesi indicated the use of both unmodified flakes and retouched tools for plant processing, and we detected evidence for the manufacture of composite tools. Microscopic wear traces on unretouched flakes show that these were attached to shafts for possible use as hafted tools, but not necessarily as projectiles. Our results suggest that simple flake assemblages can be part of complex tool production and present an alternative view on the seemingly unchanging lithic technology from the Late Pleistocene to the Holocene. Furthermore, our current understanding of expedient lithic technology should be reassessed as features that are not observable with standard morphological and technological analyses may be detected through use-wear analysis. Overall, the applied methodology and results of this study are relevant to Pleistocene and Early Holocene archaeological sites and assemblages that exhibit the dilemma of inferring technological and behavioural complexity through the analysis of simple stone tools.

A Bayesian approach to calculating Pre-Pottery Neolithic structural contemporaneity for reconstructing population size Publication date: December 2019 Source: Journal of Archaeological Science, Volume 112 Author(s): Shannon Birch-Chapman, Emma Jenkins

Ancient Mycobacterium leprae genomes from the mediaeval sites of Chichester and Raunds in England Publication date: December 2019 Source: Journal of Archaeological Science, Volume 112 Author(s): Ammielle Kerudin, Romy Müller, Jo Buckberry, Christopher J. Knüsel, Terence A. Brown Abstract We examined six skeletons from mediaeval contexts from two sites in England for the presence of Mycobacterium leprae DNA, each of the skeletons displaying osteological indicators of leprosy. Polymerase chain reactions directed at the species-specific RLEP multicopy sequence produced positive results with three skeletons, these being among those with the clearest osteological signs of leprosy. Following in-solution hybridization capture, sufficient sequence reads were obtained to cover >70% of the M. leprae genomes from these three skeletons, with a mean read depth of 4–10×. Two skeletons from a mediaeval hospital in Chichester, UK, dating to the 14th–17th centuries AD, contained M. leprae strains of subtype 3I, which has previously been reported in mediaeval England. The third skeleton, from a churchyard cemetery at Raunds Furnells, UK, dating to the 10th to mid-12th centuries AD, carried subtype 3K, which has been recorded at 7th–13th century AD sites in Turkey, Hungary and Denmark, but not previously in Britain. We suggest that travellers to the Holy Land might have been responsible for the transmission of subtype 3K from southeast Europe to Britain.

Applying luminescence dating of ceramics to the problem of dating Arctic archaeological sites Publication date: December 2019 Source: Journal of Archaeological Science, Volume 112 Author(s): Shelby L. Anderson, James K. Feathers Abstract Dating Arctic archaeological sites is challenging because of limited terrestrial bone and the high probability of old wood in northern regions. Luminescence dating of ceramic materials, abundant in western Arctic late Holocene archaeological sites, offers another potential source of chronological information. We set out to evaluate whether luminescence can provide chronological information in one particular region. We obtained luminescence ages on 14 pottery samples from seven study sites located on the coast and interior regions of northwest Alaska. Twelve of the luminescence dates are in accord with radiocarbon, tree ring, and artifact data from the study sites. Results indicate that all of the study sites may be older than previously established, suggesting previously unknown early Thule or Birnirk occupation of the coast and interior of northwest Alaska. We conclude that luminescence dating of ceramic materials from this region is possible and can complement other dating methods that are more widely accepted in the western Arctic. There is considerable potential through future applications of luminescence dating for improving northeast Asian and Arctic chronologies and expanding our understanding of circumpolar Holocene migration, cultural interaction, and change.

A brave new world for archaeological survey: Automated machine learning-based potsherd detection using high-resolution drone imagery Publication date: Available online 26 September 2019 Source: Journal of Archaeological Science Author(s): H.A. Orengo, A. Garcia-Molsosa Abstract Archaeological pedestrian survey is one of the most popular techniques available for primary detection of archaeological sites and description of past landscape use. As such it is an essential tool not just for the understanding of past human distribution, economy, demography and so on but also for cultural heritage management and protection. The most common type of pedestrian surface survey consists of fieldwalking relatively large tracts of land, recording the dispersion of items of material culture, predominantly pottery fragments, by teams of archaeologists and students. This paper presents the first proof of concept for the automated recording of material culture dispersion across large areas using high resolution drone imagery, photogrammetry and a combination of machine learning and geospatial analysis that can be run using the Google Earth Engine geospatial cloud computing platform. The results show the potential of this technique, under appropriate field circumstances, to produce accurate distribution maps of individual potsherds opening a new horizon for the application of archaeological survey. The paper also discusses current limitations and future developments of this method.