Laser Technology Meets Vanishing Treasure

National Park Service Supports High Tech Archaeology

Orinda, Calif. February 4, 2008 The National Center for Preservation Technology and Training (NCPTT), part of the U. S. National Park Service, raised the bar for documenting archaeology through a recently completed research and training grant given to Texas Tech University (TTU) and CyArk, a nonprofit project of the Kacyra Family Foundation with the mission of preserving Cultural Heritage Sites through collecting, archiving and providing open access to data created by laser scanning, digital modeling, and other state-of-the-art technologies. This grant resulted in a major step forward for the National Park Service in testing and disseminating advanced technologies and methods for documenting and preserving the many historic sites known as Americas Vanishing Treasures.

It is a tragic fact, but according to the U.S. Department of the Interior, thousands of prehistoric and historic ruins, some UNESCO World Heritage Sites, in 44 U.S. National Parks in the West alone, are threatened by deterioration and collapse. Known as Americas Vanishing Treasures, these important historic sites face imminent demise as a result of many years of inadequate funding, backlogged preservation plans, and declining numbers of caretaker staff. At present these historic sites are deteriorating faster than they are being documented.

This unfortunate loss of historic cultural sites is not unique to the United States, but is in fact a situation that is prevalent through much of the world. Unlike cultural artifacts safely housed in museums, cultural heritage sites are far more at risk, exposed to the harsh elements of sun, wind and rain and in many cases to corrosive acts of human beings that can range from uncontrolled tourism to the extreme cases of looting and acts of war. In the worst case scenario, documentation may be the only form of preservation. It is imperative that these cultural heritage sites be well documented before they deteriorate any further. However, in the best case scenario, proper documentation can be the first step toward responsible preservation and site management.

To address this challenge NCPTT gave TTU and CyArk a grant to refine a documentation process the two had developed called High Definition Documentation (HDD) and to train NPS staff at Mesa Verde, and from elsewhere among the Vanishing Treasures National Parks, in its implementation. The technological core of HDD is laser scanning which captures the physical features of a site and displays them in 3D as a point cloud model, accurate to .5cm, where each point represents the precise location of the lasers contact with the site. Ben Kacyra, founder of the Kacyra Family Foundation, was the first to develop long range laser scanning with his company Cyra Technologies (now Leica Geosystems) back in the 1990s. Laser scanning becomes HDD when high resolution and dynamic range photography and other documentation technologies are integrated with the laser scanning, providing additional material and chromatic information to the 3D point cloud model. HDD delivers a 60% time/cost savings over traditional, manual, archaeological documentation methods and is more dimensionally precise. HDD data can be used to generate a wide range of documents useful for preservation and heritage site management. For example the HDD data can generate CAD drawings, condition assessment documents, and finite element method models for structural analysis. These are of great value to heritage site managers, archaeologists, and conservation professionals. But much visually rich HDD data can also be of great use for education and of interest to the general public. Such data from cultural heritage sites from around the world can be viewed at the CyArk 3D Heritage Archive at www.cyark.org.

Fire Temple is one of the over 600 cliff dwelling archeological sites in Mesa Verde National Park. Like the other sites in the park, Fire Temple, located in Fewkes Canyon, was home to the great Ancestral Puebloan cliff dwelling civilization which reached its height in the 1200s and rapidly declined and ultimately abandoned these magnificent dwellings by 1300. The demise of the Ancestral Puebloans was due to effects of over population, environmental resource depletion, and climate change. Fire Temple is one of the hundreds of back country sites that are closed to the public. And there it is possible to find fragments of polychrome pottery and other artifacts still lying about the ground. In May 2007 TTU arrived with great difficulty at the inaccessible Fire Temple site, packing in a high tech equipment including a laser scanner, GPS, high resolution panoramic photographic equipment, a Total Station, and five laptop computers, ready to apply HDD methods. However, this was more than just an important exercise in high tech archeological documentation. It was a venue to introduce and train NPS staff in HDD.

For two weeks in May 2007, lead by TTU professor Prof. Glen Hill, over 20 enthusiastic NPS personnel participated in acquiring new skills in creating survey grid networks, GPS georeferencing, high resolution photography, and most important 3D laser scanning. They experienced, hands on, the full extent of on site field data collection. They also participated in the day-to-day data processing of the data collected, and they participated in the creation of individual 3D point cloud models from the laser scan data. Back in the lab they further processed data into stitched together 3D point cloud models, 2D archaeological maps and drawings, spherical panoramic photographs, and other interpretive media. Archaeological maps of every surface of the site were developed from the 3D laser scan data with valuable archaeological information accurate to .5cm.

To extend the successful training experience to other Vanishing Treasures National Parks personnel, TTU and CyArk conducted a two day webinar in November 2007 that reached over 90 participants from not only the U.S. but also from abroad. Over the web, these participants received an in depth introduction to all aspects of field data collection, data development, and creation of deliverables. In addition, participants were introduced to data archiving and management over the web using new web application software developed by CyArk – CyArk Site Manager.

"Mesa Verde is both a National Park and World Heritage Site. The parks 52,000 acres hold nearly 5000 archeological sites that we must care for and document, says Larry Wiese, Superintendent of Mesa Verde National Park. The amazing technology and support provided by TTU, CyArk, and Ben Kacyra, is allowing staff to document sites in a very detailed manner, with a speed previously unavailable to us. Documentation of an archeological site that would have taken many months, can now initially be done in days. The analysis includes detailed documentation, 3D imaging, structural analysis and modeling, quick access from computer files to be used by field personnel, and remote access by researchers and students. Ultimately, this is helping us to understand and protect this resource and tell a more accurate story of Mesa Verde to our national and international visitors and researchers."

Indeed bringing advanced technologies and new methods to archaeological documentation serves not only heritage site managers and conservation professionals. They also serve the general public. Certainly the public benefits when sites are better preserved and better managed, but there is another aspect to this. Of the over 600 cliff dwelling sites at Mesa Verde, only 4 are accessible to the general public. And for a variety of good reasons, there are no plans to allow visitors into the back country sites. However, through HDD other sites can be rendered virtually accessible, and will be over the CyArk 3D Heritage Archive, www.cyark.org. And by extension, Americas Vanishing Treasures can potentially all be rendered more accessible to the public at large, fulfilling this important public mission of the National Park Service. The National Center for Preservation Technology and Training has brought this possibility one step closer.

Fire Temple – the latest heritage site at Mesa Verde National Park archived on CyArk: http://archive.cyark.org/Mesa-Verde-Fire-Temple-map.php#2