Sensors of the Lost Tomb
Dr. Albert Yu-Min Lin is on a quest to locate the lost tomb of Genghis Khan. This alone is not unprecedented--many expeditions have gone before him, and all have failed in finding the elusive burial site. What is groundbreaking, however, is Lin’s methodology to locate the “Universal Leader’s” tomb without exhuming a single blade of grass.
“Unlike traditional archeological missions, our goal is not to dig,” explains Lin, a research scientist and National Geographic Emerging Explorer at the University of California San Diego’s (UCSD) Center of Interdisciplinary Science for Art, Architecture and Archaeology. “Instead, we are using technology to do our digging through an exhaustive, non-invasive survey of Genghis Khan’s homeland. Using pioneering technological techniques, we aim to piece together this ancient puzzle without disturbing the sacred land.”
To do this, Lin has become a bit of a Khan himself. He has been a technological innovator and master strategist, assembling human expertise and advanced technology, and customizing the tools to discover, visualize and analyze what lies beneath their feet.
“A lot of the tools we’re using were developed for other disciplines,” says Lin. “But we have adopted them and combined them in clever ways to add considerable value and insight that we could have never acquired with any given tool alone.”
Indeed, 3D electro-resistivity tomography (ERT) magnetometry and ground-penetrating radar (GPR) instruments have revealed promising subsurface features in northern Mongolia, which Lin’s team believe may be connected to their search. By combining GPS technology and crowd sourcing techniques, more than 10,000 “citizen scientists” have studied 85,000 high-resolution satellite images, identified anomalies and tagged them for the team to explore--an approach that ultimately guided them to their main archeological site. And for the latest, and likely last, expedition to a sacred mountain range in Mongolia last summer, the team added advanced survey technology to help build a precise spatial map of all the disparate discoveries they have made.
“Each instrument makes its own data map, and that map needs to correspond to all the other maps in order for us to make accurate sense of all the information pieces we have,” says Lin. “With survey technology, we had the means to create a very detailed, 3D topographical map of the site upon which we could align all of our other data layers, enabling us to understand more clearly the spatial and historical relationships between our findings. That has been very exciting.”
Originally named Temujin, Genghis Khan is best known as a ruthless warlord and brilliant military tactician who amassed the most advanced professional army ever in Asia. From 1206-1227 (13th century) the “Great Khan” as emperor built an empire that stretched from the Sea of Japan in the east to the Caspian Sea in the west--the largest contiguous empire in history. But that is only part of the story, says Lin.
“Few people know the whole story of Genghis Khan. He was the first to connect the east with the west, allowing for the flow of ideas, people, traders and technology. He practiced religious tolerance and recognized women’s rights. He introduced Mongolia’s written language and built infrastructure still in use today. And he was a technological leader. He adapted new technologies from conquered enemies and used them in innovative ways, like creating a sophisticated postal system and flag-signaling system to coordinate communication.
“This is a story from Asia that has had a huge impact on our modern world that hasn’t been told,” he continues. “I wanted to explore that.”
To begin, Lin started at the end--the 785-year-old mystery of Khan’s final resting place, a story as lost as the story of the man himself. Indeed, the only definitive fact surrounding Khan’s unmarked burial site is that there is no recorded fact, only legends, suppositions and myths. The only potential clue is that a 500-square-mile area bordered by Mongolia’s Onon River and the Khan Khentii mountains near Khan’s birthplace in Khentii Aimag was deemed a Forbidden Zone directly after his death in 1227, leaving many to believe the 65-year-old Khan was buried somewhere there.
Limited access to the region began in 1991, with the fall of the former Soviet Union in Eurasia, but only a smattering of archeological expeditions have been permitted to explore and none has found Khan’s tomb. Complicating the hunt further is that many Mongolians view the location of the tomb as sacred and believe any desecration of it could trigger a curse that would end the world. Japanese archaeologists terminated a search in 1993 for the tomb after a poll in the country’s capital Ulaanbaatar found the project unpopular.
“Using conventional archeological methods would be disrespectful of local traditions,” says Lin. “Treading lightly with non-invasive technology to excavate sites of interest, without disturbing the ground or local traditions, allows us to empower Mongolian researchers with tools they might not normally have access to and add to their knowledge base about this heritage.”
Lin officially launched the three-year Valley of the Khans* project in 2008, spending the first year formulating the project and laying the groundwork for expeditions. The first full-scale expedition to the region was in July 2009, followed by two more exhaustive surveys in 2010 and 2011. With each expedition, Lin has not only increased his arsenal of cutting-edge technological tools and international team of industry experts--the 2010 expedition had six different digital imaging instruments, 11 laptops, 31 men and 16,000 online explorers--he has returned with new discoveries, new insight and new resolve to further lighten his satchel of unknowns.
“Previously we used an old-school measuring tape to map out our survey grid patterns,” says Lin. “That was not only time consuming, it wasn’t interactive. With the advanced geophysical tools we were using, we needed to have technology that could precisely and efficiently survey our site, and allow us to integrate our other sensor data with the survey data to create a 3D, georeferenced topographical map. A 3D map would give us the platform to incorporate our other data pieces and relate our findings to a broader context of the region’s geography and social climate of the time.”
The Trimble VX was added to the team’s technological tool chest for the August 2011 trip, with the primary purpose of laying out Arc Site 1 and collecting location points for every artifact found in between.
Each morning, Jeremiah Rushton, the designated “Trimble Man,” hoisted the survey equipment onto his back and hiked up the mountainside to the 100-meter by 30-meter (300-by-100 foot) site. After setting control, Rushton and another team member methodically moved through the site in a grid pattern, collecting a point every square foot to ensure there were no data gaps, and also taking measurements of objects discovered at the site. Operating the unit remotely using Trimble Access field software on a Trimble TSC2 Controller, all data was uploaded to a laptop for nightly processing, producing near real-time mapping information to help them better plan the next day’s strategy. The team logged about 1,000 data points a day for 10 consecutive days–that is, when they weren’t dodging thunderstorms.
“One day, a storm developed out of nowhere, and it got so cold and wet so fast that I almost threw up,” recalls Rushton, a PhD candidate at UCSD. “Lightening strikes were fast approaching, so we had to quickly pack up and sprint down the trail, which had already turned into a river. We just made it back to our yurt in time.”
Indeed, the frequent rain required much ingenuity from the team to protect their high-tech instruments. For the survey equipment, they affixed a rice bowl over the instrument’s prism as a protective “hat” and used a solar panel as a canopy to protect the VX unit. Rushton himself donned a protective mesh hood for shelter from the clouds of man-eating bugs, while guarding his own “forbidden zone” around the instrument--team members would unknowingly step too close to the instrument tripod set on the soft ground and disrupt the station setup. Despite the challenging environment, the team successfully mapped the entire site, down to each individual tree--all 200 of them.
It worked. Attaching the prism to the radar antennas, the VX recorded a point every half second as the GPR was pushed along the ground. That georeferenced GPR data could then be overlaid on the topographical map to add further spatial and historical depth to their findings and better focus their exploration.
“The ability to bring datasets together, centralized around a georeferenced network, helped us to better understand and visualize our data,” says Lin. “And that allowed us to adapt our search strategy in real time as well.”
After returning from the field, Lin and his team began integrating their myriad data layers with the survey-based topographical map, overlaying satellite imagery, aerial imagery, ERT data and GPR data to build a 3D seamless visualization of the entire site. They then brought that visual information into the StarCAVE, a five-walled, totally immersive virtual reality room in a laboratory at UCSD that allows users to fly-through and interact with 3D landscapes in such a potentially dizzying sensation that there are handrails available for support.
Anchored by a 3D georeferenced map, Lin and his team were able to see the area with new eyes, Lin says. “The topographical map allowed us to clearly see the anomalies that we had been studying, both on the surface and below, and their relationships,” says Lin. “It helped us understand why we suddenly stopped finding artifacts in certain areas, or make sense of why we were finding remains in certain areas, or why we had data gaps in certain sensors. Equally important is it confirmed our study footprint as well as gave us new areas of focus. It’s insight we could not have gleaned without the accurate map.”
So does all of this verification mean Lin’s team has found the lost tomb of Genghis Khan? For now, Lin is keeping that answer buried as deep as the tomb itself. There is still much information to process and much data to share with his Mongolian colleagues. What is clear, however, is that whatever the outcome, Lin will not be seen with a shovel in hand digging up the presumed location.
“Digging was never my goal with this project,” concludes Lin. “That is a decision for the local Mongolian people to make. I wanted to prove that you can push technology in ways it was never intended to produce the most exhaustive, non-destructive research I can, and apply this knowledge to the betterment of the Mongolian people. I think I’ve done that.”
* The Valley of the Khans project is an international collaboration between the University of California at San Diego, the Mongolian Academy of Science and the International Association for Mongol Studies, and the National Geographic Society. It is funded in part by the NGS/Waitt Institute for Discovery, the National Geographic Expeditions Council, UC San Diego, and industry and private support.
Dr. Lin and his team extend their appreciation to Trimble’s Chad McFadden for his extensive support and training on the Trimble VX.
For more information about Lin’s research, visit www.albertyuminlin.com. Additional details about Trimble equipment and software can be found at www.trimble.com.
Valley of the Khan Team Members» Dr. Shagdaryn Bira, Secretary General of the International Association for Mongol Studies, Co-Principal Investigator
» Dr. Fredrik Hiebert, Archeologist, National Geographic Archaeology Fellow, Co-Principal Investigator
» Professor Tsogt-Ochiryn Ishdorj, Deputy Director of the International Association for Mongol Studies, Co-Principal Investigator, Mongolian Expedition Leader
» Dr. Nathan Ricklin, Field Systems Engineer, California Institute for Telecommunications and Information Technology (Calit2), UCSD
» Dr. Alex Novo, Environmental Engineer, Geophysical Survey Specialist
» Dr. Shay Har-Noy, Computer Vision Engineer, Calit2, UCSD
» Dr. Kostas Stamatiou, Historical Research, Calit2, UCSD
» Dr. Albert Lin, Research Scientist, Calit2, UCSD, National Geographic Society Emerging Explorer, Principal Investigator