Flights into the past: full-waveform airborne laser scanning data for archaeological investigation

Airborne Light Detection and Ranging (LiDAR) is a quite recent (mid-1990s) remote sensing technique used to measure terrain elevation. Recent studies have examined the possibility of using LiDAR in archaeological investigations to map and characterize earthworks, to capture features that may be indistinguishable on the ground and to aid the planning of archaeological excavation campaigns.     

Towards a Risk Management and Conservation Plan for the Djin Blocks at the World Heritage Site of Petra,Jordan: The Case of Djin Block No. 9

Cultural heritage is subjected to many pressures and risks. Over the past few years, the use of digital technologies has significantly changed the approaches to cultural heritage documentation for the purpose of condition assessment and conservation. The integration of novel approaches and techniques has permitted a detailed examination and assessment of damage, deterioration due to weathering and erosion, and their mechanisms. This study seeks to contribute to the preservation and conservation of the significant heritage of the so-called Djin Blocks at the World Heritage Site of Petra in Jordan. While these three dimensional cuboid rock-cut monuments have been subject to extensive conservation studies, this is the first time they have been subjected to 3D recording and multispectral photography, with the aim of recording damage caused by the ravages of time.

This study presents the results of the documentation of the case study Djin Block No. 9. A variety of systematic documentation techniques were used, including 3D recording with terrestrial laser scanning (TLS), close-range photogrammetry, multispectral imaging, and thermography records. In addition, pathological studies of the erosion from various causes and an analysis of the effect of weathering on Djin Block No. 9 are performed. Based on this data, the paper presents recommendations for developing risk management and conservation planning of Djin Block No. 9.     

Emerging Applications of LiDAR / Airborne Laser Scanning in the Management of World Heritage Sites

Remotely sensed data and imagery have revolutionized the way we understand archaeological sites and landscapes. LiDAR / airborne laser scanning (ALS) has been used to capture the often subtle topographic remnants of previously undiscovered sites even in intensely studied landscapes, and is rapidly becoming a key technology in survey projects with large extents and/or difficult terrain. This paper examines the practical application of this technology to archaeological heritage management, with special attention given to how ALS can support the World Heritage List nomination process and management of WHS archaeological sites and landscapes. It presents a number of examples from published ALS studies alongside case studies from projects undertaken by the authors at Cultural Site Research and Management and the Cultural Site Research and Management Foundation, Baltimore, Maryland, USA. The paper opens with a review of how ALS has been used at established World Heritage Sites, focusing on the Archaeological Ensemble of the Bend in the Boyne, Ireland, and the Angkor Archaeological Site in Cambodia. ALS applications for site prospection and demarcation, and viewshed analysis is explored in this section. Following this, we explore how ALS has been used to support two recent applications: the successfully nominated Monumental Earthworks at Poverty Point, USA and the recently nominated Orheiul Vechi Archaeological Landscape in Moldova. We propose that the detail offered by ALS data greatly strengthens nomination dossiers by emphasizing the outstanding universal value of sites, highlighting significant features and providing greater context to wider landscapes, and is particularly efficacious in delineating site boundaries for legal protection and long-term management. Finally, we conclude with a look at some of the practical considerations involved in the use of ALS, including access and training.     

Novel use of cathodoluminescence to identify differences in source rocks for Late Paleoindian quartzite tools

Heterogeneous quartzite artefact finds from North America's Late Paleoindian period occur in several areas throughout the Northern Great Lakes region. Standard petrographic analysis, back-scatter scanning electron microscopy and cathodoluminescence are used to identify the properties of a regionally abundant, high-quality orthoquartzite stone as compared with high-quality Hixton silicified sandstone from the Silver Mound Archeological District in Jackson, Wisconsin. The results demonstrate the potential for reducing misidentification among material sources, and also exhibit the acutely discerning tendencies of pre-contact peoples. Lithological interpretations of thin sections identify the different properties of the Hixton material. Conversely, Mesnard quartzite, while it functions adequately as a tool stone, is fundamentally compromised of a tightly packed microstructure. This microstructure produces a hard, less tractable material with erratic breakage, possibly explaining Mesnard quartzite's limited distribution prehistorically.     

A Chain Pump Recovered from the Wreck of the Warship Northumberland (1703)

In 2008 the remains of a chain pump were recovered from the wreck of the third‐rate man‐of‐war Northumberland, which sank on the Goodwin Sands in the English Channel, during the Great Storm of November 1703. Chain pumps were vital equipment and integral to the safety of the ship. Historical evidence is mined for comparative material, and the recovery, conservation strategy, study and recording of this artefact using X‐ray and CT scanning are discussed. Information gleaned, hitherto absent from the historical and archaeological record, includes details of the pump's chain, hook and swivel, valves and roller.     

Salt Effects in Plastered and Unplastered Outdoors Brick Masonry: Quantitative Laser Monitoring of Surface Decay Evolution

In masonry materials, the superficial decay is a widespread problem. Aggressive environmental agents such as moisture and salts trigger the damage by propagating through the material capillary pores. Although several studies have been carried out on salt crystallization and their damaging effects, additional research effort is required to better investigate this phenomenon on real cases and real weathering conditions. To this purpose, testing and monitoring tools capable of following degradation process since the early beginning are necessary. Repeated visual inspections are commonly used to monitor the superficial decay, but this technique is subjective and thus not capable of providing any quantitative information. In this work, an experimental campaign, carried out in Bologna, Italy, is presented. A two-header brick wall, one main face unplastered and one plastered, was stored outdoors and exposed to weathering over two summers. Before the start of the second aging season, moisture and salt capillary rise was simulated by low-concentrated sodium chloride solution (0.1% -wt). The aim was to favor solution evaporation and salt crystallization and to provoke material damage. The degradation process was monitored based on a contactless, rapid and accurate image diagnostic technique. In particular, high-resolution laser scanning by triangulation technique was adopted. Three-dimensional data acquisition was repeated at the end of both seasons. The proposed procedure successfully extracted quantitative information approximately areas of material spalling and detachment even in the initial phases of decay.     

Three-dimensional (3D) visualisation: the application of terrestrial laser scanning in the investigation of historical Scottish farming townships

Recent developments in digital technologies are heralding significant changes in the way we acquire, visualise and analyse archaeological data. Terrestrial laser scanners can be used to create photo-realistic virtual copies of landscapes, and archaeological features, and offer the potential to improve our understanding of three-dimensional (3D) spatial relationships at study sites. Here we present a methodology for the integration of a high-resolution 3D site model with soil chemical data obtained from an abandoned settlement site located in the Central Highlands of Scotland. At this site, the multi-element concentration in soil, co-visualised within a topographic setting, has an important role to play in elucidating settlement layout and activity. The methods described here are also of significance in archiving sites of archaeological/historical importance where development activities and/or environmental processes may destroy remains, or where access to field sites is restricted.     

Virtual skeletons: using a structured light scanner to create a 3D faunal comparative collection

Appropriate comparative animal skeletons are not always available to faunal analysts for use in identifying archaeofaunal remains. This is especially pertinent when working in locations where no comparative collections are available locally, and the archaeological assemblage cannot be transported to another facility. In order to fill this gap, we are building a virtual comparative faunal collection using a structured light scanner to scan modern skeletal material in 3D. The resulting high resolution 3D color models are a valuable resource for identifying fossil specimens. Scan data can be converted into a variety of formats for viewing and can be transported on a portable digital device for use at field or laboratory localities. In addition, scans can be printed three dimensionally to produce a replica of the scanned skeletal part. A particular advantage of this digital technology is that we can eventually create a complete 3D representation of a taxon's skeleton from scans of several components of what are incomplete skeletons of one animal taxon in a museum collection. The results of our project thus far are available to other researchers and educators by means of the internet. A variety of interested parties could benefit from such a collection, including zooarchaeologists, paleontologists, biologists, teachers and museum curators.     

Archaeological prospection of forested areas using full-waveform airborne laser scanning

Airborne laser scanning (ALS) is a potential tool for recognising and measuring topographic earthwork features in wooded areas. To explore its potential for archaeological reconnaissance in a densely forested area, a test scan covering an Iron Age hillfort in the eastern part of Austria was carried out during the first phase of a research project.     

Lisht as a New Kingdom Glass‐Making Site with Its Own Chemical Signature

Lisht is one of a few New Kingdom sites with known glass‐working debris. Here, we present evidence for the primary production of glass at Lisht, including crucible fragments and semi‐finished glass. We also provide 12 new chemical analyses of glass from Lisht, including trace elements. We argue that the glass made at Lisht has a specific chemical signature within the broader range of Late Bronze Age glass compositions from Egypt, further underlining the former existence of primary glass production there and offering the possibility of identifying Lisht‐made glass elsewhere in Egypt and beyond.