The future of Archaeology.
Introduction. Human person webcitizen reading this.
Howdy, this is just a little bitty that I wrote up after doing a whole lot of research for a paper a while back, I mailed it to google, because I think they need to make a Google:archaeology.. What Anthropology, and Archaeology are missing, which is of incalculable value to learning more about how Human People came to be as we are as a species. What we need is a way to collaborate seamlessly in Data Sharing and site, artifact, and architecture documentation around the world.
It would be AMAZING… a time shift-able skin for google earth, that lets you transform the continents through the ages (including all up to date data on when and where the various extinct species ranged… For Anthropocene era, Incorporating multiple layers, from the satellite, to aerial photos to site level photos and zooming ALL the way down to digital microscopy… Including all the recent studies of various wavelength imaging techniques, like infrared capturing data on plants, and along with the most up to date research, and site data, and perhaps integration, and assistance for Archaeologists labs around the world….
Well, here it is google:internets (since you didn’t respond to my loving message{I understand why, it being 25 pages long
…I really think this is the fit you want for a model of your data sharing vision; you speak of wanting to “be the worlds new Alexandria”… You do this by by first bringing together the collected knowledge and wisdom of our Scientists and Social Scientists who are collecting, discovering, exploring, documenting, and recording…This is a noble goal, one you are currently taking a piecemeal approach to, but the technology and scientists and technicians are out there… waiting for partners in a project to establish a valid, and useful resource for the dissemination of knowledge regarding the Earth, its’ past, and the amazing Evolution of Life. Start where Alexandria started… with History.
Imaging and Exploration of Archaeological Data in the Digital Realm
Preamble
Picture Google Earth, you zoom in, the Mediterranean, the Nile, Cairo, three massive pyramids cast intimidating shadows just miles out of this modern urban city, you are now at an aerial photography layer, you continue to zoom, now at a digital photographic layer, incorporating 360o digital photographic panorama, you click and drag your mouse to “look around”. As you zoom in further, your perspective changes as you select the orientation of someone on the ground. You notice a glowing point somewhere around ten feet up from the base of the pyramid; local researchers have added their discoveries as digital hyperlinks. Here they have placed giga-pixel quality images of hieroglyphs that are of vital importance to discovering who built these amazing monuments. Was it Khufu, or another, earlier dynastic king?
Now you gain seamless access to the photo-micrographic close-ups of the huge block of limestone, bearing the overlay of an inscription upon its surface. The international community of Egyptologists has worked together, and through one click, it is possible to view translations of this ancient legacy language. Like a modern day Rosetta stone, the language translator allows you to read the hieroglyphs in your language of choice. At this scale, it becomes possible to compare crystalline features, and match up the source quarry that provided the limestone rock used in the construction, further, you are able to see the microscopic evidence that at one point these massive structures were encased in a sheath of the most brilliant hard white limestone.
Introduction
One inherently negative aspect of fieldwork in archaeology is that excavation is a “destructive” event. The site excavators, no matter how careful and well trained they may be, are removing the layers that give context to a site, and disturb the provenances within a site. These features and concurrent context will be forever lost— unavailable to future researchers, who may have been able to glean more from the site than the person who carried out the excavation (e.g. see Nickens 1991). More is lost as the backhoe is brought in to “clear” some of the area so that a few small sub-quadrats can be carefully dissected with hand trowels and horsehair brushes. From this perspective, traditional methods represent a very crude approach to exploration of such precious sites, in that the investigator has to use some judgment on where to focus, discarding much of the potential search area as they follow proper statistical sub-sampling procedures (Fagan and DeCorse 2005 pp177-181). Inevitably, the sample will be only part of the story, and the exploration may be at the wrong scale to represent how the space was actually used. The traditional “dig” will not only destroy potential, scientifically vital, elements of the original context, but it will erase that potential archaeological data from the record forever.
This paper will explore the proposition that we should place more emphasis on digital techniques that would allow us to replace, or at least augment, this destructive, limited, “one time only” style of research with an array of tools including digital, optical, and even simple hand drawn field sketches. We should integrate the wide array of digital techniques that exist today and share data in common formats so that the modern archaeologist and all who follow, including members of the public, will have the ability to understand the context and provenance of sites that we will preserve, rather than tear apart (Nickens 1991). There are a number of exciting techniques available or in development for visualizing of sites and perceiving subtle features within landscapes and of transposing them into hypermedia. There are problems and challenges encountered when navigating, recording, and analyzing forms of landscape-related artifacts such as prehistoric “monuments”, land art, sculpture parks, and landscaped gardens (Fagan and DeCorse 2005 p 201). In particular, techniques will be discussed for examining and recording both the local properties, including texture, form, weathering, and construction techniques of sites, and the wider attributes such as relationship of artifacts to their site, topography, relationships between surrounding sites, and geological context.
It is widely recognized that much important archaeological information is buried in storage facilities and in yellowing, unpublished field notes (Banning 2000, p132); I would argue that geo-referenced digital databases are exactly what we need to catalog the work and discoveries that have already been made, while we develop the tools to correlate, integrate, and speculate on our past, and perhaps find our way into the future on this planet.
Not incidentally, of course, digital media present archaeologists with an excellent opportunity to bring the public “on board” to support the conservation of archaeological sites in the same way as popularization of biology and ecology has led to an awareness and interest in protecting the biodiversity of the rain forest and endangered species. This could help stem the tide of construction and development that irrevocably disturbs sites of great potential importance. If members of the public could take virtual tours of the impressive archaeological sites both as they are now, and as they were at the time they were built and in use, that could reignite a passion and curiosity about humanities origins. Both the “community learning” aspect of “digital archaeology” and preservation of cultural heritage will also be further discussed.
SCALES OF REFERENCE
Wide Scale: Geo-Terrain Analysis
The goal of analysis at this scale is to identify good candidate sites for more detailed exploration. Using GIS-based approaches, and incorporating a variety of types of data, it is possible to postulate how the world once was, and to predict where people once were based on inferences about, for example, the locations of ancient lake shores, paths and hunting settlements as well as variations in vegetation and terrain that hint at previous structures and activities of people, and their relationships to the many varied climates earth has experienced during the time of humans.
Tools and methods
Remote sensing is just one element of a nonintrusive or nondestructive archaeological methodology, and includes a wide array of detection systems that are continuously being developed due to their concurrent importance to security and military applications, and to various scientific endeavors. Generally speaking the costs are very high relative to typical research budgets, but where the data are being collected anyway, for other purposes, it is very valuable if researchers can have access to such valuable data sets. Tools range from what is now a relatively “lower-tech” approach of aerial photography using different detection systems, such as aircraft-borne sensor imagery (ABSI), Sideways Looking Airborne Radar (SLAR) to satellite-based detection systems such as Satellite Sensor Imagery (SSI) (Fagan and DeCorse 2005, pp181-199; Gurmerman and Lyons 1971). (See Appendix A for details on remote sensing technologies).
Some well-known sites discovered through geo-terrain analysis methods
There are several notable cases where examination of these wide area, aerial, and space-based imaging techniques has been used to great success. For example predicting as yet unfound sites along the Delaware coastline, using GIS and attributes of known sites as a guide; finding, and confirming as real, rather than legend, the Ubar site in Oman, and the discovery of long-lost or at least forgotten sites of the ancient Pueblo Indians around Chaco Canyon.
Delaware coast: predictive surveys
A very good recent example of application of geo-terrain analysis would be the study by Custer et al. (1986), of the Delaware coast where they used knowledge about existing sites and their attributes, to predict where new (so far unrecognized) sites might be. The authors used LANDSAT remote sensing data to generate archaeological predictive models by identifying where the coast would have been at different times in prehistory. They did not focus on the specific sensing of archaeological sites, but instead used a synoptic approach to identify the likely environmental settings for archaeological sites. They used logistical regression to quantify the association between site locations and measured or mapped environmental variables. By analyzing the environmental variables associated with known site locations, and known non-site locations, the logistical regression provides a probability assessment of an unsurveyed area’s potential for containing archaeological sites. Supervised classification of LANDSAT data generates maps of environmental zones that can be related to the environmental variables used in the logistical regression. The model and the LANDSAT classifications have been tested and found to give accurate assessments of site potential in unsurveyed areas, as well as measures of the accuracy of the assessments. Results can be applied to cultural resource management problems and also yield useful data on prehistoric land use patterns (e.g. see Silbernagel et. al. 1997).
The lost city of Ubar
Another excellent example of the application of digital geo-terrain surveys was the discovery of the location of the legendary city of Ubar, a desert caravansary that supported the ancient and lucrative frankincense trade from about 2000 BC to about 300 AD (Blom et. al. 1997). Frankincense is the dried sap of Boswellia Sacra, which grows principally in this region. In the ancient world frankincense was used for religious ceremonies, medical purposes, and cremations. It was so valued that it was literally “worth its weight in gold” in ancient Rome. Ubar is located at the edge of the Arabian Peninsula’s “Rub-al-Khali” or “empty quarter”, in what is now Oman. The legend was that Ubar was buried in a sandstorm as a punishment from God for bad behaviour. The field data suggest that much of the fortress collapsed into a sinkhole, likely caused by overuse of groundwater to irrigate the surrounding oasis. The site was found using a combination of historical research, in the form of accounts from Ptolemy (his maps were lost when the Library at Alexandria was destroyed), notes from British explorers Bertram Thomas and T.E Lawrence (Lawrence of Arabia), who dubbed Ubar “Atlantis of the Sands”. This study is a perfect combination of space age technology and traditional archaeology (Blom et. al. 1997).
Chaco Canyon
The Chaco Canyon Research Center had already started to build an archaeological database in the form of aerial photography and a ground survey, when thermal infrared multispectral data were added (Sever and Wiseman 1985). A Thermal Infrared Multispectral Scanner (TIMS) was flown by NASA over Chaco Canyon in spring of 1982 (and later followed by further survey flights). This instrument measures temperature differences near the ground, to a resolution of 5m. The scan revealed something that had not been visible by any other surveys either from the air using traditional, as well as colour and IR photography, or from the ground; it exposed the routes of prehistoric roads from 900-1000 AD. There were over 200 miles of a prehistoric roadway system, as well as walls, buildings and fields. Sever proposed that Chaco Canyon was a regional social and religious centre. The study raised more questions about the people of the area: how were the roads, 7m or more in width, surveyed to be so straight, and how were they constructed by people who did not have “beasts of burden” to assist? The road system allowed long distance movement from the edges of the San Juan Basin and beyond, to reach Chaco Canyon (Sever and Wagner 1991).
Local Scale: Within Sites
Digital methods can be used to model the current state of sites, to reconstruct past states, display data, and provide complete visual reconstructions of buildings or structures that are in ruins today.
Tools and methods
Layers of information from satellite and aerial imaging can be juxtaposed to generate detailed data in the form of GIS maps, where data can be combined in different ways at the discretion of the investigator to provide new perspectives. Similarly, a wide variety of techniques can be used within-sites to develop layered understanding of context, extent and interactions between components of the site. Data of course need not be solely photographic; they can be based on other inputs such as Microwave radar, Magnetometry and X-ray surveys, electrical resistivity tomography, ground-penetrating radar, induced polarization, seismic tomography, reflection seismology, and acoustic tomography.
Many of the methods used in this aspect of archaeology (detailed in Fagan and DeCorse 2005 pp187-200) have been adapted from mineral exploration techniques. In general, geological applications are concerned with detecting relatively large structures, often as deeply as possible, but most archaeological sites are located within the top 1m of the soil. For archaeology, therefore, detectors are often adjusted to focus on this layer. Another challenge is to detect subtle and often very small features, which may be as ephemeral as organic staining from decayed wooden posts, and distinguish them from rocks, roots, and other non-anthropogenic materials. This requires higher resolution, with, usually, 1-50 readings per square meter.
Microwave radar is based on beaming radar pulses into the ground and measuring the echo; this is useful for finding buried artifacts in arid regions (water absorbs microwaves). Typically artifacts tend to reflect the microwaves, providing a picture of what is underground without excavating the site. Most commonly applied to archaeology are magnetometers, electrical resistance meters, ground-penetrating radar (GPR) and electromagnetic (EM) conductivity meters. These methods give excellent resolution of many types of archaeological features, are capable of high sample density surveys of very large areas, and of operating under a wide range of conditions. Regular metal detectors can be used as geophysical sensors, but they don’t give high-resolution imagery. Other established and emerging technologies are also being adapted for archaeological applications.
Electrical resistance meters are like the Ohmmeters used to test electrical circuits. Metal probes are inserted into the ground to obtain a reading of the local electrical resistance. A variety of probe arrangements are used, most having four probes, often mounted on a rigid frame. Archaeological features are detected when they are of higher or lower electrical resistance than their surroundings. For example, a stone foundation might impede the flow of electricity, while the organic materials in a midden might conduct electricity better than their surroundings. To some degree this approach can be used in the vertical as well as the horizontal plane but this method is not particularly good for detecting variations in depth.
Three-dimensional (virtual) reconstructions
The concept of reconstructing heritage scenes in a virtual world carries with it the same concerns about the integrity and accuracy of the information, as does the creation of museum displays, documentaries and other forms of communication of scientific information. There is always a tension between providing a more complete “story” with the resulting personal engagement, and remaining true to the accuracy of facts that are actually known, versus inferences or speculations.
Perhaps particularly exciting in this area, there are a growing number of examples of virtual reconstruction of buildings and structures (Whitcher Kansa et al. 2007). Chen and Kalay (2008) have explored the idea that there needs to be a “hook” to the narrative sequence of visual experiences while touring an archaeological site (be it virtual or real). The question arises, is it valid to include narrative aspects to virtual tours?
In the research world there are wonderful opportunities to use such viewing systems as Computer-Aided Virtual Environments (CAVEs). Most people lack access to such sophisticated tools, and even to modern PCs, but augmented reality and immersive public presentation can be achieved at centers where the general public can experience their virtual heritage (Addison 2000). It would be prohibitively expensive to reconstruct life size models of buildings and other artifacts, but the fact that these virtual databases are readily edited means that things can be changed in the light of new information, making the virtual viewing experience ever more accurate. As that process of refinement proceeds, new methods and detection systems can be incorporated to augment the existing understanding.
Image-based rendering is an alternative to the approach that is based on the capacity of computer graphics systems to recreate the perception of “being there” in a three-dimensional space (Snavely et al. 2008). Without a need for additional programming, design artists, or the complex process of polygon rendering, this relatively simple process compiles immersive, explorable 3-D virtual worlds from large libraries of ordinary images. Through a collaboration between researchers at the University of Washington and Microsoft, Snavely et al. (2008) designed software which collates images, “as the user browses the scene, nearby views are continuously selected and transformed, using control-adaptive re-projection techniques” (meaning images are rotated and adjusted geometrically so that a stable view of an explorable environment is provided). Input is based on a set of photos taken from a variety of viewpoints, directions and conditions, taken with different cameras, and potentially with many different foreground people and objects.
Small Scale: Artifact Reconstruction, Display, and Manipulation
Tools and methods
In a review of 3-D data retrieval methods for examining pottery, Kampel and Sablitnig (2006) outline four areas of application of digital techniques. The first is a two-laser scanner method, which creates a 2-D image of the profile of an object (e.g. a potsherd) to facilitate reconstructions. The second involves using an LCD projector to help measure the depth of focus to provide the information needed to make a 3-D reconstruction or representation of an object. The third method discussed by Kampel and Sablitnig (2006) uses a Minolta Vivid-900 camera with the capacity for colour separation, and uses a laser to triangulate and essentially to scan the artifact. This setup can be used in the lab, but is too big to use in the field. However the fourth technique they describe, the ShapeCam method does allow field data collection. This system is based on use of a Sony TVR-900E digital camera combined with a Leica slide projector. A grid is projected onto the object and the object is viewed from different angles, capturing the 3-D shape. The authors concluded that the greatest accuracy and speed of data collection were possible with the Minolta Vivid-900 method; however the costs of that apparatus are in the order of $100,000. Other methods each had different advantages and disadvantages depending on the material of study (Kampel and Sablitnig 2006).
Novati et al. (2005a) point out that the traditional approach to data acquisition is to use RGB (full colour) devices; however the results of these depend on the environment (particularly lighting), which will affect the perceived colour of objects that are imaged. A better approach, they argue is to use a multispectral imaging system that works in a similar way to a regular RGB device, but that uses a greater number of sensors capturing more than the standard red/green/blue information in the electromagnetic spectrum (Nakauchi 2005). Using simple RGB colour capturing devices, different colours can appear to be the same, depending on the lighting, and the individual observer, so there are clear advantages to multisensor arrays. A modern adaptation of this approach is to have a single monochrome sensor, but to use different filters to cause different spectral segments to be received and then to reconstruct the colour elements of the image (Brettel et al. 2000; Poger and Angelopoulou 2001). The great advantage of multispectral imaging is that the durable, faithful storage of information on colour of an object can be achieved; this “digital master” provides a stable repository of data that will retain its usefulness and richness of data, as inevitable evolutions occur in computing technology. Also, an electronic record does not deteriorate with time, as would a standard 3-colour photograph (Novati et al. 2005a)
Image mosaicing is a very valuable approach for reconstructing a larger object from several partial images. In these applications it is necessary to take an array of images (tessels), and match up and “stitch together” adjacent and overlapping details in order to produce a smooth, continuous, high definition, and consistent image where there are no apparent geometrical or colour distortions (e.g. see Peleg and Ben-Ezra 1999; Novati et. al. 2005b). This is analogous to the previously mentioned process of stitching together adjacent aerial photographs or other images for GIS, at the larger scale.
When an artifact is being examined in the virtual world, the curator can avoid such strategies as contamination with modern glues, or embedding in plaster or other substrates in order to view under the microscope, even bypassing the simple, yet risky, act of cleaning and handling. Also the artifact is not exposed to needless risk of damage (Suraj 2005). The virtual data can also be sent to experts anywhere in the world, making it more likely that insights will be gained. The original is not at risk when a copy is being made. Making a digital “mold” of a lithic tool does not create the same risk as making a plaster mold and replica of the same object.
When artifacts have 3-D structure (for example carvings or paintings on a curved or uneven surface) it may not be enough to document them in a planar manner. Using 3-D laser range scanners, colour and shape data can then be merged to generate more realistic representations (e.g. Shum and Szeliski 1997).
Examples of Application of Digital Methods at the scale of the artifact
Just as at the largest scale original land uses can be uncovered by overlaying and comparing different sets of information, the curation and restoration of artworks can be greatly enhanced by examining the artifact using different visualization techniques and overlaying and comparing them. For example, in the difficult area of art restoration, the original piece can be viewed and compared with the appearance of the object following restoration. etc… (Marras et al. 2005). These researchers used IR, and colour images with UV fluorescence and a high resolution 3-D measurement system to expose the series of restorations that had taken place with reference to the painting, Madonna dei Fusi, attributed to Leonardo da Vinci. They showed that the lower part of the child’s face had been severely degraded, and had been restored; it also showed more subtle restoration of the child’s forehead, cheek and neck where the multichannel colour sensor allowed the detection of “tonal non-homogeneities”, or subtle differences in the colours. The addition of 3-D information to the other data allowed very sensitive detection of the full extent of the restoration, details that would not have been noticed (and indeed had not been noticed) even by expert examination.
The 3-D information was developed using a conoscopic micro-profilometry device, which uses holographic principles to develop a 3-D visualization (see Asmus 1978; Charlot 1988). Marras et al. (2005) emphasized the point that data integration is an important feature of this approach. The ability to combine and compare sets gathered with various techniques allows new results and better understandings of an object (or indeed a site).
Future Applications: Digital Teaching Tool, Research Tool, and Opportunities for the Better Preservation of Cultural and Physical Heritage
Most archaeologists today are using computers, digital cameras and other sensing instruments in their research as well as conventional materials such as notes, field samples, etc. Web-based archives such as “Open Context” (www.opencontext.org), and other organizations such as Cy-Ark 3-D Heritage Archive Network, provide open access data publication services for archaeology, where copyright to the ideas and data rest with the author (rather than the publisher, as is the case for most print journals). An advantage of Open Context is its flexible, generalized technical architecture that can accommodate most archaeological datasets, despite the variety of recording systems in use. (It has the same flexibility and simplicity to submitting research, as making a FaceBook page, with less potential for embarrassment). Authors are clearly identified with full citation tools, and web-based publication systems allow individuals to present their own data for review. Collaboration is also facilitated through easy download and “tagging” features (Whitcher Kansa et al. 2007).
Although we live in the age of global connectivity, with speed-of-light transmission of data, in quantities that eclipse the sum of data accumulated by our species to the present day, the scientific community remains scattered, with very few ways of sharing data and collaborating on its analysis. Archaeological data, according to Whitcher Kansa et al. (2007) is in a state of disarray, and they express the concern that research data are in danger of being ephemeral, simply because “archaeological data sharing is not living up to its full potential”. Opportunities for publication of detailed information are limited, and despite the declining cost of electronic data capture and storage, most scholars still lack the means and/or the incentive to share their field data. To address this problem, Whitcher Kansa et al. (2007) advocate, and have established, a forum for scholarly publishing that allows useful field data to be freely accessed. This structure also generates opportunities for scholarly collaboration.
Whitcher Kansa et al. (2007) also call attention to the difficulties and legacy costs of using proprietary software; upkeep and changing computer systems call for a continual cost cycle (meantime locking out potential collaborators who do not have the necessary resources, as well as members of the public who might become engaged in inquiry, given an open system to explore). An internet data repository allows sharing of information that could never see publication in part because the sheer mass of the data content could not be accommodated in print publications. “Thousands of bones, seeds potsherds, lithics and other artifacts and ecofacts that are analyzed and recorded as well as maps photos and log entries associated with a typical project almost never see publication beyond the summarized form” (Whitcher Kansa et al. 2007).
Looking Ahead
The very inaccessibility of field data poses an under-recognized threat to cultural heritage preservation as the original data may reside in the files of a single investigator. This is a problem whether the data are in digital or physical form. It could be argued that it is irresponsible to allow this potential loss of heritage information, and therefore not only the new digital information needs to be posted, but also data, notes and other information collected by archaeologists of the past need to be digitized and posted, ideally with commentary from the researchers themselves. Attention to this task would be an excellent assignment for young archaeologists, reminiscent of the mission undertaken by Colin Renfrew (Baron Renfrew of Kaimsthorn) who showed his respect and appreciation of his visiting colleague, Lewis R Binford by helping to assemble the first draft of his 1983 book, “In Pursuit of the Past”, by making tapes of Binford’s lectures during his visit to Britain. Renfrew felt that otherwise Binford, who really preferred being out in the field, would never get around to the task.
The new digital tools outlined in the present report include electronic distance measurement devices (EDMs), global positioning systems (GPS), digital cameras, video recording, and handheld data-entry devices. As a result much more data is being collected than was possible with traditional paper and photographic records. Electronic storage costs are becoming increasingly cheaper (according to Moore’s law the costs and size of data storage is declining exponentially) and instruments continue to be able to capture ever-greater detail even in the most remote field sites.
Whitcher Kansa et al. (2007) believe the Internet provides a place where museum collections and excavation documentation could be shared. Many museums now display portions of their collections online and some research projects have online databases documenting their excavation and survey results. For example, the CyArk 3-D Heritage Archive Network provides a searchable archive of free 3-D scans and maps of World Heritage sites. The pioneering Perseus Digital Library has a rich and ever growing collection of texts, images, and other media for classical studies and other areas, while the Cuneiform Digital Library makes an impressive collection of early Near Eastern texts openly accessible. The public is getting involved as well. For instance, the commercial photo-sharing site “Flickr” has over fifty thousand photos of items in the British Museum, contributed by public enthusiasts for the historical and aesthetic achievements of the past.
Data-Sharing Challenges in Archaeology
Among the primary technical and conceptual issues in sharing field data is the question of how to standardize our documentation. Archaeologists generally lack consensus on standards of recording and tend to make their own customized databases to suit the needs of their individual research agendas, theoretical perspectives, and time and budgetary constraints (see also Denning 2003; Hodder 1999). Because of this variability, databases need extensive documentation for others to decipher their contents. This type of documentation is often called “metadata,” or “information about information.” Metadata, such as titles, keywords, author, and catalogue numbers, enable library users to find relevant publications. Likewise, metadata documentation associated with archaeological datasets can help others find and decode those data. However, adding useful metadata to content typically requires time and expertise, thereby deterring many from sharing.
Perhaps with a wider dissemination of the knowledge and cultural wisdom imparted through archaeology, the problem of “grave robbers”- or modern day “artifact collectors” would decline. If more of the knowledge that is currently locked away in “grey literature” became accessible, and manipulable by the public, there might be a revolution in the appreciation that where we come from guides where we are going.
Similarly, Novati et al. (2005a) remind us that museums typically have many more artifacts than they have space to exhibit them. A digital catalog would allow objects that would otherwise collect dust, to be viewed by the public at a digital terminal. If the images were stored as a searchable database, any researcher in the world would be able to view specimens, and might make connections with other specimens they have seen or measured. Going even further, digital “arcaves” could be archives in 3-D, in the form of VR-caves where a visitor or an investigator could enter an environment where the collection was placed in the original location within the site, to be encountered in a historically accurate context.
Just as species are going extinct each day, especially in the rich and biodiverse rain forest, on a daily basis important archaeological sites are disappearing due to development. It is very important that archaeologists transmit to the public a sense of urgency to protect these sites that parallels the biologist’s passion to protect endangered species. It should not be a difficult task; every human being at some time is intrigued by the question, “where did I come from”? It is archaeology, perhaps through the lens of electronic reconstruction and virtual tours of past sites that can provide many of the answers, if we act in time. The online storage of data should not be considered the permanent “New Library of Heliopolis”- but for the present, we, the societies of the Earth need all the chances we can to co-operate and collaborate, in our pursuit of answers regarding our origins and evolution.
These new methods will never completely replace traditional archaeological fieldwork (Fagan and DeCorse 2005, pp71-72), but I would suggest that a visionary goal for the next decade of archaeology would be to make the archaeology of the past more accessible, and the archaeology of the future less invasive.
REFERENCES
Addison, AC. 2000. Emerging Trends in Virtual Heritage. Multimedia IEEE Vol.7 (2): 22-25.
Asmus JF. 1978. Holograph interferometry of painted surfaces. In, Conservation of wood in Painting and the Decorative Arts, Oxford Congress, IIC. pp 141–144
Binford, LR. 1983, 2002. In Pursuit of the Past: Decoding the Archaeological Record. Thames & Hudson Pub. NY, NY.
Banning EB. 2000. The archaeologist’s laboratory: the analysis of archaeological data. Springer. Berlin, Heidelberg. 316 pp., p132.
Blom R, Zarins J, Clapp N, and Hedges GR. 1997. Space Technology and the Discovery of the Lost City of Ubar. Paper read at IEEE Aerospace Conference, Feb 1-8 (available at IEEE website).
Brettel H, Hardeberg JY, Schmitt F (2000) WebCam for interactive multispectral measurements. In: Conference on colour image science (CISrsquo2000), Derby, UK, 10–12 April 2000
Charlot D. 1988. Holographie conoscopique – reconstructions numeriques, Annales des Telecommunications pp 23–26, 1988.
Chen X, and Kalay Y. 2008. Making a Liveable ‘Place’: Content Design in Virtual Environments. International Journal of Heritage Studies Vol. 14(3): 229–246.
Custer TE, Klemas V, and Wells, I. 1986. Application of LANDSAT Data and Synoptic Remote Sensing to Predictive Models for Prehistoric Archaeological Sites: An Example from the Delaware Coastal Plain. Society for American Archaeology.
Custer TE, Gross D and Shankman, P. 1988. Cultural and Ecological Applications of Remote Sensing. Final Report of a Conference Sponsored by the National Science Foundation, University of Boulder Colorado, Boulder. April, 1988.
CY-ARK 3-D Heritage Archive Network http://archive.cyark.org/
Denning K. 2004. The “Storm of Progress” and Archaeology for an Online Public. Internet Archaeology 15. Online: http://intarch.ac.uk/journal/issue15/denning_index.html.
Desmond LG and Sauck WA. 1996. Entering the Maya Underworld: A ground penetrating radar Survey at Chichen Itza, Yucatan, Mexico. Innovation et Technologie au Service de Patrimoine de l’Humanite, Actes du colloque organise par Admitech en collaboration avec l’Unesco. Paris, 24 June 1996, pp. 23-30.
Fagan BM and DeCorse CR 2005. In the Beginning: An Introduction to Archaeology. 11th Edition. Prentice-Hall. New Jersey, USA. 578 pp.
Gurmerman GJ, and Lyons TR. 1971. Archaeological Methodology and Remote Sensing. Science Vol. 172 No 3979: 126-132.
Hodder I. 1999. Archaeology and Global Information Systems: Internet Archaeology 6. Online: http://intarch.ac.uk/journal/issue6/hodder_toc.html.
Kampel M. and Sablatnig R. 2006. 3D Data Retrieval of Archaeological Pottery. In, Interactive Technologies and Sociotechnical Systems. Springer Series: Lecture Notes in Computer Science. Volume 4270. Springer Berlin Heidelberg, pp 387-395.
Marras L, Fontana R, Gambino MC, Greco M, Materazzi M, Pampaloni E, Pelagotti A, Pezzati L, and Poggi P. 2005. Integration of Imaging Analysis and 3D Laser Relief of Artworks: A Powerful Diagnostic Tool. In, Lasers in the Conservation of Artworks. Springer Proceedings in Physics, Volume 100. Springer Berlin Heidelberg, pp 485-492.
Nakauchi S. 2005. Spectral imaging technique for visualizing the invisible information, in: Proc. of the Scandinavian Conference on Image Analysis, Joensuu, 2005, pp. 55–64.
Nickens PR. 1991. The destruction of archaeological sites and data. In, Smith, GS, and Ehrenhard, JE. (eds.), Protecting the Past, CRC Press, Boca Raton, FL, pp. 73-81.
Novati G, Pellegri P, Schettini R. 2005a. An Affordable Multispectral Imaging System for the Digital Museum. International Journal of Digital Libraries, Special Issue on Digital Museum, Vol. 5 (3): 167-178.
Novati G, Pellegri P, and Schettini R. 2005b. An experience in multispectral mosaicing. SPIE (The International Society for Optical Engineering. Vol. 5667: 84-94.
Open Context Archaeological Data Sharing Site. http://www.opencontext.org
Peleg S, Ben-Ezra M. 1999. Stereo panorama with a single camera. In: Proc. IEEE international conference on computer vision and pattern recognition (CVPRrsquo99), pp 395–401
Poger S, Angelopoulou E. 2001. Selecting components for building multispectral sensors. IEEE CVPR technical sketches (CVPR Tech Sketches). IEEE Press, New York
Recheis W, Weber GW, Schaefer K, Knapp R, Seidler H, zurNedden D. 1999. Virtual reality and anthropology. European Journal of Radiology 31: 88–96
Reijmer CH, Knap WH, and Oerlemans J. 1999. The Surface Albedo Of The Vatnajökull Ice Cap, Iceland: A Comparison Between Satellite-Derived And Ground-Based Measurements. Boundary-Layer Meteorology 92: 125–144.
Shum H-Y, Szeliski R. 1997. Panoramic image mosaics. Microsoft Research, Technical Report, Redmond, WA.
Sever TL. 1998. Validating Prehistoric and Current Social Phenomena upon the Landscape of the Peten, Guatemala. In People and Pixels: Linking Remote Sensing and Social Science. National Academy Press. Washington D.C.1998.
Sever TL, Miller F, and Lee D. 1991. Applications of Ecological Concepts and Remote Sensing Technologies in Archeological Site Reconnaissance (In, eds C Behrens and TL Sever Applications of Space-Age Technology in Anthropology. NASA, Stennis Space Center, MS.
Sever TL, and Wagner DW. 1991. Analysis of prehistoric roadways in Chaco Canyon using remotely sensed digital data. In Trombold, C. D. (ed.), Ancient Road Networks and Settlement Hierarchies in the New World, Cambridge University Press, Cambridge, 277 pp., pp. 42–52.
Sever TL and Wiseman J. 1985. Remote sensing and archaeology: potential for the future. NSAS Earth Sciences Laboratory, Picayune, MS.
Silbernagel J, Martin SR, Gale MR, Chen J. 1997. Prehistoric, historic, and present settlement patterns related to ecological hierarchy in the Eastern Upper Peninsula of Michigan, U.S.A. Landscape Ecology 12: 223–240, 1997.
Snavely N, Garg R, Seitz SM, Szeleski R. 2008. Finding Paths Through the World’s Photos. ACM Transactions on Graphics (Proceedings of SIGGRAPH 2008) Vol. 27(3): 11-21.
Suraj VK. 2005. Multimedia Information Collection in Digital Libraries. Gyan Books, 312 pp., p 81.
Turner BL and Harrison PD. 1983. Pulltrouser Swamp: Ancient Mayan Habitat, Agriculture, and settlement in Northern Belise. University of Texas Press, Austin.
Whitcher Kansa S, Kansa EC, and Schultz JM. 2007. An Open Context for Near Eastern Archaeology. Near Eastern Archaeology 70 (4): 188-201.
APPENDIX A
Remote Sensing Methods
Methods are summarized from details in Fagan and DeCorse 2005, and the NASA JPL Remote Sensing Website available at http://wwwghcc.msfc.nasa.gov/archaeology/remote_sensing.html
Aerial Photography has been a powerful tool since organized fly-overs have long been used to survey and explore sites. Features which are difficult or impossible to see from ground level can become strikingly clear from the air, for example the Cerne Abbas Giant, also known as the “Rude Man” a chalk drawing of a naked man wielding a club on a hillside in a village in Dorset (http://www.sacred-destinations.com/england/cerne-abbas-giant.htm). Topographic variations, in particular, can be seen in terms of shadows, crop colour variations (due to differential water availability where there are underlying structures), soil variation and related vegetation composition). However black-and-white photography only records about twenty-two perceptible shades of grey in the visible spectrum, so successful aerial photography (like any ground based photography) obviously requires daylight, clear weather, and low haze. In addition when flyovers occur under different conditions there are challenges to matching up adjacent runs of the photographic series in terms of these tones of grey.
Color Infrared Film (CIR) detects longer wavelengths just beyond the red end of the visible spectrum. This technique was developed during WW II to identify objects that had been camouflaged. IR photography has the same challenges as black-and-white photography in that light and clear skies are necessary. However, CIR can detect very slight differences in vegetation; this has special value in archaeology (ref). Since buried remains can affect how plants grow above them, variations in vegetation can help pinpoint potential sites of interest.
Thematic Mapper technology (TM) was installed in the two most recent Landsat satellites; its sensors collect seven bands of image data (three in visible wavelengths, four in infrared). This system has been particularly useful in the study of albedo in relation to glacial melting and global climate change (Reijmer et. al. 1999). Unfortunately TM Landsat instruments generate low resolution images, where each pixel represents about a 30m x 30m square, so are useful in archaeology at the large scale of tracking such large features as roadways and large settlements, and are less useful in site-level archeology.
The Thermal Infrared Multispectral Scanner (TIMS) is a NASA designed aircraft scanner with six channel spectral capability in the thermal infrared region of the spectrum. It can measure the thermal radiation given off by the ground, to an accuracy of 0.1Co. The pixel (picture element) is the square area being sensed, and the size of the pixel is directly proportional to the height of the sensor above ground. Pixels in TIMS have much higher resolution than the Landsat TM system, and so are particularly useful for archeological research.
LIDAR (Light Detection and Ranging) is an optical remote sensing technology that measures the distance or range to an object. It is widely used in both military and scientific contexts. The range to an object is determined by measuring the time delay between transmission of a pulse and detection of the reflected signal. Airborne Oceanographic LIDAR (ADI) is a laser device that generates “profiles” of the Earth’s surface in a manner analogous to sonar (sound-based) or radar (radio wave-based) sensing. A laser beam pulses to the ground 400 times per second, striking the surface every three and a half inches, and bounces back to its source. Minor variations in topography, to the scale of worn footpaths, can be detected. The LIDAR data can also reveal tree height as well as elevation, slope, aspect, and slope length of ground features. The beam bounces off the top of the vegetation cover and off the ground surface; the difference between the two gives information on the height of the vegetation. LIDAR can also be used to penetrate water to measure the morphology of the coastal shelf, detect oil forms, fluorescent dye traces, water clarity, and organic pigments including chlorophyll. In this case, part of the pulse is reflected off the water surface, while the rest travels to the water bottom and is reflected. The time interval between the received impulses indicates water depth and subsurface topography.
Synthetic Aperture Radar (SAR) beams energy waves to the ground and records the energy reflected. Radar is sensitive to ground topography, and is valuable when different radar wavelengths and different combinations are made of horizontal and vertical data. The degree of penetration of different Radar wavelengths depends on vegetation and properties of the surface. In dry, porous soils, radar can penetrate the surface. For example, in 1982, space shuttle SAR data revealed ancient watercourses in the Sudanese desert; airborne radar has traced prehistoric footpaths in Costa Rica.
Synthetic Aperture Radar (SAR) has been particularly useful in locating canals and irrigation systems (Sever, 1998). SAR is a type of radar that is can delineate geometric features on the ground. Ground Penetrating Radar (GPR) has been performed on a number of sites, including Chichen Itza; this has detected buried causeways and structures that might have otherwise have been missed ((Desmond and Sauck 1996).
Sideways-Looking Airborne Radar (SLAR) is really a variant on SAR that was developed for oil exploration. It detects terrain on either side of the airplane’s transect, and has been particularly useful for tracing ancient roads, disturbed sites, and underwater sites and shipwrecks. Fagan and DeCorse (2005) relate how the technique was used by Turner and Harrison 1983, to identify a complex of irrigated terraces dating to the period 200BC-850AD, where maize, amaranth and perhaps cotton were grown.
