Digs Go Digital

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If you’ve ever wanted to volunteer on an archaeological dig, our annual guide to excavations has all the info you need to find a dig that’s right for you. And when it comes time to pack for your trip, don’t forget your hat, sunscreen, work gloves—and your laptop.

With all of the amazing scientific advancements in recent years, digs are doing more than ever to incorporate hi-tech tools and to digitize their work for quicker, more accurate results—from Web sites to wi-fi and ground-penetrating radar to GPS. We offer here just a few examples of what’s being done at Holy Land digs of the 21st century. But none of it is possible without real people working on the ground, so read up, grab your boots and your Blackberry, and get out there!

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3-D Scanning: Automating Pottery Drawings

Who We Talked To: Avshalom Karasik, the Hebrew University, Ph.D. student in math and archaeology.

How It Works: Pottery sherds are scanned in using special three-dimensional cameras. A computer program calculates the proper position and central axis of symmetry for each vessel, using various algorithms and formulas. The computer can then use this information to create standardized archaeological profile drawings of each fragment. This is carried out as part of the computerized archaeology project of Dr. Uzy Smilansky at the Weizmann Institute of Science and supported by a grant from the Israel Science Foundation.

How It Helps: In the past, drawings of individual pottery fragments were done by an excavation artist and could take several hours each, so only a small sample of an excavation’s thousands of sherds were chosen for drawing. These drawings were also inevitably subject to human bias and error. With the 3-D scanner and computer, publication-quality drawings can be produced for more than 100 fragments in the course of an 8-hour day. This increases both the accuracy of the drawings themselves (correct to within 0.1 mm) and the percentage of sherds from an excavation that can be analyzed. This higher level of accuracy also provides helpful information about subtle stylistic differences that might otherwise be difficult to pick up.

Who Can Use It: The development of the method and algorithm behind the technology requires knowledge of theoretical math and/or computer programming, but the use of the equipment requires only two or three days of training.

Future Possibilities: Right now the 3-D scanning technology is useful only for obtaining the profile of diagnostic rim fragments of symmetrical vessels. Karasik and others hope to develop methods for reading and interpreting other kinds of fragments, as well as color, texture, paint and other attributes. For now, though, no technology can replace an expert eye where those are concerned.

Residue Analysis: Scraping the Bottom of the Pithos

Who We Talked To: Dvory Namdar, post-doctoral research fellow at the British Museum.

How It Works: Experts scrape the surface of a vessel or take a small piece of it (if possible). The sample is then crushed completely and washed with organic solvents to bring out any organic materials, which are then extracted for analysis. Using a gas chromatography instrument, the molecules are separated according to mass, weight, electric charge or other 032distinguishing factors. The scientists then try to identify the molecules using mass spectroscopy, a process by which ions are shot at a particle and will react in a predictable way based on what substance it is. From this information, they can identify the type(s) of food products that were once contained in the vessel.

How It Helps: Knowing whether an ancient storage jar contained oil or wheat or wine is certainly interesting, but it provides important information for bigger archaeological questions, such as who was trading what with whom and why? Residue analysis was used to identify degraded beeswax in a few ceramic containers excavated at Tel Rehov a year before the installation could be recognized as an apiary.

Who Can Use It: This research utilizes knowledge in a variety of scientific fields, including chemistry, biology, physics and biochemistry of food, but Namdar stresses that a background in archaeology is crucial for understanding the larger questions and focusing research.

Future Possibilities: This process is not an easy one because many factors—location, environment and site history—affect the preservation of the molecules. Now that the technology has proven effective, sites such as Tel Dor are being prescreened to determine areas most likely to produce usable samples. Namdar also hopes to continue studying broader archaeological questions such as whether 033or not the ancient Israelites ate pork and how certain types of vessels were used for particular cooking methods or dishes.

High-Precision GPS: Getting the Lay of the Land

Who We Talked To: Stefan Münger, University of Bern (Switzerland), codirector of the Kinneret Regional Project.

How It Works: The use of GPS (Global Positioning Systems) on digs has been around for a few years, but the latest developments in high-precision GPS mean that users can walk around an excavation site with a handheld GPS measuring stick, called a Rover, and get readings within a few seconds. GPS technology uses the positions of satellites (which aren’t in short supply over the Middle East) to calculate the precise locations of walls, finds and other features in three dimensions with an accuracy of 1.5 centimeters.

How It Helps: This method is much faster, easier and more accurate than using the old survey tools. Instead of having to lug out bulky equipment for only the most significant finds and features, now every elevation and the location of every little bead can be quickly and accurately taken. This information can be integrated 035into a database for creation of daily top plans and other uses.

Who Can Use It: Unlike the older construction-type survey equipment, any volunteer can be easily trained to take elevations with the high-precision GPS unit.

Future Possibilities: At Tel Kinrot, they’re working to develop a more sophisticated GIS (Geographic Information Systems) database and photography systems that will integrate GPS and other data in a user-friendly excavation-level interface. Accurate, time-saving tools like these will free up the archaeologists even more to spend their efforts on the ground, doing the real handiwork of archaeology.

Archaeological Field Labs: Getting Results in Real Time

Who We Talked To: Aren Maeir, Bar-Ilan University, director of the Tell es-Safi/Gath Archaeological Project, and Steve Weiner, director of the Kimmel Center for Archaeological Science at the Weizmann Institute of Science.

How It Works: The team at Tell es-Safi/Gath set up a laboratory in the actual excavation area, as well as another at the nearby field camp, which facilitates the processing of materials as they are excavated. The labs include tools for infrared spectrometry, optical microscopy, UV-VIS spectrophotometry, flotation and phytolith concentration, all of which are used to identify and analyze organic and inorganic samples taken from the trenches. The team also 036includes a radiocarbon-dating expert who ensures that good samples are taken from suitable archaeological contexts and prescreens them in the lab to check their quality.

How It Helps: The field labs promote close collaboration between archaeologists and scientists to produce the best results. Rather than having to wait weeks or months to get lab reports on excavation findings, the archaeologists can get results in a matter of minutes or hours, thus enabling them to make on-the-ground tactical decisions about where to focus excavation time and resources.

Who Can Use It: Although some of these complex lab methods are reserved for the experts, others can be used by all team members, such as the infrared spectrometry, which showed that most of the floors at Gath were made of crushed chalk rather than plaster.

Future Possibilities: Not only will field labs lead to faster results and better allocation of resources, but they have also prompted the Tell es-Safi/Gath project and the Weizmann Institute to open a joint archaeological science field school during the summer excavation season. This allows future archaeologists to get interdisciplinary training in the many scientific fields that influence archaeological research, all fully integrated into a large-scale excavation.

GIS Excavation Database: Putting All the Pieces Together

Who We Talked To: Thomas Levy, Center of Interdisciplinary Science for Art, Architecture and Archaeology at the University of California, San Diego, and codirector of the Edom Lowlands Regional Archaeology Project (ELRAP) in Jordan.

How It Works: GIS stands for Geographic Information Systems. During an excavation such as ELRAP, every aspect is recorded digitally—from GPS survey points to field notes and photography—and each special find and locus is given a unique ID number. ELRAP uses three cross-checks to ensure accuracy of the data. Using this system, called “on-site digital archaeology,” these data can all be tagged and cross-referenced for easy access and interpretation.

How It Helps: The digital database brings together precise information from every aspect of an excavation. For example, for a single ceramic vessel, GIS can quickly provide the find spot, linked excavation top plans, area maps, conservation photos, supervisor’s notes, drawings and long-term storage information for that one piece of pottery.

Who Can Use It: Willing volunteers can be trained in the proper recording and retrieval processes in just a few hours, and all team members are encouraged to learn about the various parts of the database system.

Future Possibilities: Having the overwhelming quantity of excavation information readily available in one comprehensive digital format will expedite the publication process by facilitating the study and interpretation of the finds, as well as easily compiling relevant charts and drawings. Levy is working with Steve Savage of Arizona State University to develop a “cyber-infrastructure” of linked digital archaeology atlases for the Mediterranean region, called MedArchNet. The first atlas of the Holy Land is underway at http://daahl.ucsd.edu/DAAHL.

If you’ve ever wanted to volunteer on an archaeological dig, our annual guide to excavations has all the info you need to find a dig that’s right for you. And when it comes time to pack for your trip, don’t forget your hat, sunscreen, work gloves—and your laptop. With all of the amazing scientific advancements in recent years, digs are doing more than ever to incorporate hi-tech tools and to digitize their work for quicker, more accurate results—from Web sites to wi-fi and ground-penetrating radar to GPS. We offer here just a few examples of what’s being done at […]