http://voices.nationalgeographic.com/2017/01/30/how-technology-accelerates-the-search-for-sites/
How New Technology Accelerates the Search for Ancient Sites
Posted by Sarah Parcak of National Geographic Fellows Program in Explorers Journal on January 30, 2017 Citizen scientists have discovered a cluster of galaxies millions of light years away. They've logged data that proved there was citywide lead contamination in the water in Flint, Michigan. They've rallied attention to a mass die-off of sea stars. And today, they will begin mapping Peru, using GlobalXplorer.org to scan specially-processed satellite imagery for signs of ancient sites that modern archaeologists don't know about.
GlobalXplorer is the citizen science platform I've built with the 2016 TED Prize, to train a 21st century virtual army to help look for signs of archaeological looting, urban encroachment and sites that haven't been excavated yet. It felt right to launch the platform with users searching Peru, a country rich in cultural heritage, with ancient sites created by many different cultures at many different time periods. Unsecured sites are targets for looters—and GlobalXplorer users will help archaeologists get there first. Traveling across Peru's arid highlands and dry coastal deserts would take archaeologists several lifetimes on foot. With GlobalXplorer, the mapping of the country could happen in a matter of months.
Around the world, I believe that hundreds of thousands—possibly millions—of ancient sites lie hidden, and that means our shared human story is at risk. Satellite imagery is a powerful new tool that gives us eyes in the sky. We can process images captured from space in a way that lets us see patterns in the vegetation and the soil that might signal a manmade feature, hidden from view. Using satellite technology, my colleagues and I have pinpointed what we think might be a suburb of Itj-tawy, the ancient capital of Egypt. We've located what appears to be the lost amphitheater of Portus in Italy. We've scanned the eastern coast of Canada and found a site that suggests the Norse might have pushed further into North America than previously believed. And we located a massive monumental platform in Petra, Jordan that archaeologists might have been walking over for decades.
Using satellite technology and the power of the crowd, I believe we'll find and protect an incredible number of ancient sites, which could offer new clues into who we are as human beings. Why am I so confident in this? Because, all around the world, archaeologists are using new technology and discovering amazing things. Their finds are rewriting our history, showing that we lived bigger and more boldly than ever we could have imagined.
Take my friend and colleague, Dr. Damian Evans, whose team scanned 734 square miles around Angkor Wat in Cambodia in the most extensive LIDAR survey to date. LIDAR is another form of remote sensing, where data is collected from an air-based platform — either an airplane, or helicopter or drone. LIDAR works by sending down laser pulses and recording the rate of return. It lets you build a point cloud map of the landscape below. It's expensive and depends on good weather, but LIDAR is powerful for seeing what's underneath dense vegetation.
Evans' ambitious survey, detailed in the Journal of Archaeological Science, upends what we know about Angkor Wat. His team discovered multiple medieval cities hidden on the forest floor. These cities are between 900 and 1,400 years old and large in size—comparable to Cambodia's capital, Phnom Penh. The size shows the tremendous number of people needed to maintain the site's temples and the complex waterways around them. These cities suggest that the Angkor Empire was much larger than previously thought—potentially the largest in the world in the 12th century.
Drone mapping offers another top-down perspective of sites. My colleague Dr. Morag Kersel has used this technology in Jordan to map huge numbers of looting pits at the ancient site of Fifa for the "Follow the Pots" project. The 5,000-year-old graveyard here looks like the surface of the moon—it's pockmarked with looting pits, about 3,700 of them in total. Looting began here about 60 years ago, but accelerated in the '80s and '90s. Walking through the site now requires crunching through piles of dirt, bones, and artifact fragments left behind by looters. Kersel's team has created a topographic map of all the graveyard's walls, tombs, and trenches. By comparing it to excavation work done at the site in 1989, they've shown how objects have moved around the site. The data they've generated boggles the mind, and gives new insight into how looters operate—which this team has further supplemented by interviewing many involved in the trade.
Drones are lightweight, easy to transport, and inexpensive—and with them you have a lot more control over image resolution than you do with LIDAR or satellite remote-sensing. You can focus on specific parts of sites that interest you, and get your data immediately. But there are drawbacks. Drones aren't legal everywhere in the world, and they don't work well when it's windy. Still, drone mapping software is relatively easy to use, and allows you to create 3D models of sites. That can be incredibly helpful.
In the satellite imagery GlobalXplorer's search, they'll be able to see archaeological features like this very clear stone structure on top of a hill. It appears to be a defensive structure. (Image ©DigitalGlobe 2017)
The field of archaeology is sprawling, and technological approaches come so fast and furious that it's almost impossible to keep up. Amazing work is also being done with DNA analysis—my colleague Dr. Christina Warinner, for example, has examined the microbial DNA in fossilized plaque to reconstruct the diet of ancient civilizations. Advances in archaeological dating mean that we can do chemical analyses on residues found in ancient pots and vessels to get a better understanding of things like when chocolate became a staple, and that we can look at microwear patterns of ancient tools to determine how people used them. Plus, high-performance computing is starting to play a role in archaeological discovery. As our data sets get bigger and bigger, we need more power to process.
Technology opens new doors of scientific inquiry and exploration—and that gives me so much hope for the future. My dream with GlobalXplorer is for the world to come together to find and protect ancient sites. With this technology, we can democratize exploration. A hundred years ago, archaeology was for the rich. Fifty years ago, it was mainly for men. Yesterday, it was for academics. Today, it's for anyone. Because if we really want to learn about our past, it's time we inverted the pyramids.
With the 2016 TED Prize, Sarah Parcak has built GlobalXplorer and invites anyone with an internet connection to help locate and protect ancient sites. DigitalGlobe has provided satellite imagery; National Geographic Society has contributed rich content; you'll provide the analytical power. Start exploring »
[Updated 1/31/2017]
-- Sent from my Linux system.
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