Scanning the Past

Archaeologists travel to Guatemala to document a recently discovered,

2,300-year-old Mayan stucco frieze.

 

 

 

Choppering 500 feet above the mountains and jungles of Guatemala to one of Mesoamerica’s most remote archaeological sites isn’t standard fare for most university professors. But for USF archaeologists Travis Doering and Lori Collins, it’s just another day’s work in the field.

 

The recent discovery of a 2,300-year-old Mayan stucco frieze at El Mirador, in the Petén region of Guatemala, led the two USF researchers to the site in May. Doering and Collins are directors of the university’s Alliance for Integrated Spatial Technologies (AIST). Along with anthropology graduate student Bart McLeod, they were invited by Richard Hansen, director of the Idaho State University Mirador Basin Project, to three-dimensionally document the carved stucco panels with laser scanners for cultural heritage preservation and research purposes. Given the unique expertise of Doering and Collins in high-resolution 3D scanning of Mesoamerican antiquities, AIST was a natural choice to conduct the work on the ancient panels.

 

El Mirador is more than the largest and one of the earliest Mayan settlements – it is considered the second largest archaeological site in the Western hemisphere. Under threat from logging interests, artifact looting and the drug trade across the Mexican border, the Mirador Basin is biodiverse and expansive. The archaeological site covers approximately 500,000 acres, dwarfing Guatemala’s famous Tikal ruins, the country’s largest tourism draw.

 

“We were asked to document the frieze for its preservation and conservation. They’re going to be doing some restoration and they wanted to capture it in its full detail before any of the work started,” says Doering.

 

Illustrating reptilian creatures, deified monsters and anthropomorphic swimmers, the two, 26-foot-long panels are noteworthy as the earliest depiction of the characters in the Popol Vuh, a Mayan creation myth. Sculpted of limestone and stucco, the miraculously preserved pre-Christian mural suggests that the Maya’s complex creation tale far predated their contact with the Western world. Its location, as part of an aqueduct system, deepens our understanding of how the Maya harvested rainwater and funneled it across the Acropolis of the now jungle-covered ruins.

 

Utilizing short and mid-range three-dimensional scanners that direct lasers across a surface – whether it be a small artifact or entire Mayan temple – the AIST researchers create a three-dimensional file with accuracy down to a human hair.

 

“We’re capturing millions of spatially related points, essentially X, Y and Z coordinates, in what looks like a photograph, but is in fact a dense point cloud of data that records the object or area in its entirety,” says Collins. “The accuracy levels make it seem like you are actually in front of the piece.”

 

The scans provide a wealth of measurable spatial data and reveal contours and surface detail that photographs and the human eye often miss. The data maintains the spatial perspective and prevents any bias that a lens or camera position might impose on an object. In addition, unlike plaster casting or ink rubbings that can damage a fragile object, a visual representation is created without harming the original piece. “It’s non-contact, non-invasive and non-destructive,” says Doering.

 

Among the end goals of the project is to utilize the scan data to replicate the original piece for off-site display as part of El Mirador/Maya exhibitions in European museums. With the Internet’s capacity to share information on a worldwide scale, scan data is crucial to the creation of accurate virtual museum environments, allowing researchers to study archaeological sites and artifacts remotely. The research project was made possible by the Foundation for Anthropological Research and Environmental Studies (FARES), sponsor of the Mirador Basin Project, and through permission from the Instituto de Antropología e Historia (IDAEH), the Guatemala agency responsible for the protection and maintenance of the nation’s cultural heritage.

 

“Scan data offers the ability to see things as they really are and interact with the objects and sites in a virtual environment without needing to go there, like a time traveler in your own chair in front of the computer,” says Collins.

 

The time travel is set to continue: AIST has received a National Science Foundation grant to return to Guatemala to scan and analyze the monumental stone sculpture at the 2,500-year-old archaeological site of Takalik Abaj in early 2010.

 

 

 

 

 

 

 

 

This story, written by USF Photographer Joseph Gamble, originally appeared in USF Magazine, Fall 2009.

Photos by Joseph Gamble/USF and FARES