Satellite Technology and Simple Hand Tools Lead to the Discovery of Lost Cities

"Lost City" in China.
George (Rip) Rapp, Project Director
Exposing the earthen wall of a "lost city" in China.

"They're digging in the wrong place." - Raiders of the Lost Ark

Courtesy of National Science Foundation
May 19, 2007

Even with a decade on the sixties-ish actor who plays archaeologist Henry "Indiana" Jones, George "Rip" Rapp easily gives his fictional counterpart a run for his money in terms of professional accomplishments, having discovered not one, but two, "lost cities" in China; located the ancient shoreline of Troy; and excavated dinosaur fossils alongside the famous paleontologist Jack Horner in Montana.

But all of his professional successes, Rapp is quick to point out, are attributable to nothing more—and nothing less—than a good grasp of geology and the willingness to indulge in some backbreaking physical labor.

For Rapp, finding a lost city, he says, is not the fruits of hours spent learning obscure languages or deciphering ancient codes, but from applying his technique—a blend of modern technology and manual labor—to solving a geological challenge.
Temperamentally, and in terms of technique, the fictional hero, and the actual archaeologist could not be more different, though, while he has never seen the Indiana Jones movies, it is easy to imagine Rapp, regents professor of geoarchaeology at the University of Minnesota, as not unlike the studious Henry Jones, Sr, Indiana's father and a character in the third film.

Rapp, for example, took a recent telephone call working at his dining room table…on one of the four books he has in various stages of preparation.

And, while the public might like to imagine that when he discovers the outlines of a city buried for thousands of years under the Chinese earth, Rapp's face is bathed in a golden light—just as Jones' is when he finally discovers the lost "Well of Souls" with the help of a jeweled headpiece, a staff and a leather-bound notebook full of formulas—nothing could be further from the truth.

Having satisfied himself after a great deal of painstaking physical labor of taking soil cores with handheld tools to establish the outlines of an ancient city wall, that he really had found the rampart that surrounded what is now known as Huanbei Shang City—which Chinese records led experts to believe existed, but whose existence had never been proven—Rapp and his colleague, Zhichun Jing, barely paused.

Having satisfied himself after a great deal of painstaking physical labor of taking soil cores with handheld tools to establish the outlines of an ancient city wall, that he really had found the rampart that surrounded what is now known as Huanbei Shang City—which Chinese records led experts to believe existed, but whose existence had never been proven—Rapp and his colleague, Zhichun Jing, barely paused.

"We didn't break open any champagne," he says. "We had to finish tracing out the wall."
Which is not to say he does not love his work, he emphatically does.

"It certainly makes you pleased because that's why you're out there," he says. "But, at the end of the day, I am trying to use my knowledge to solve problems that are important to historians."

The Chinese Institute of Archaeology invited him to search for the first capital of the Shang dynasty through a colleague while he was teaching at Boston University. The Shang was the first literate society in East Asia.

The search had been on in China for the city for decades without success.

Then K.C. Chang, a renowned archaeologist at Harvard University, said to his colleagues, in effect, "you guys have been looking by traditional methods for 40 years. You're going to have to engage a guy like Rapp who uses satellite imagery and geophysical techniques and coring if you want to find it."

Using satellite data and ground-based geophysics, but primarily his coring technique, Rip and Jing, in 1992, discovered, not the first capital of the Shang, but China's most famous lost city, the "Great City Song" (pronounced "Soon"), which features prominently in China's ancient  literature. This city was the capital of the Eastern Zhou Dynasty.

"We had to drill 180 holes before we hit the rammed Earth walls of the Great City Song," Rapp says. The pace was grueling, drilling "two holes a day, maybe three, using a hand drill, not a power drill."

He and Jing then moved their research to the modern city of An Yang where they "went out in the field with a whole bunch of Chinese hand-coring groups and I spaced them a meter apart," Rapp says. "We were actually testing the technique. I wanted to see how fast we could do it. And 'boom,' we stumbled across Huanbei Shang City."

But, Rapp points out, contrary to methods of his fictional counterparts, "We discovered all this, though, not by finding a whole lot of great and valuable artifacts, but by finding a small number of artifacts at the right level under the ground."

In other words, the "ah ha moment" was not, unsurprisingly, quite as Hollywood might have staged it.
While in the popular mind archaeology is about discovering great things, including "lost cities," few people know how that is done, though they probably prefer to believe the "reel" to the real version.

"People are interested in discovering things, sure," Rapp says. "But in the limited experience I have, people don't know how you go about discovering."

For Rapp, a self-described geoarchaeologist, it all goes back to geology, which gives him the edge of thinking in three dimensions, rather than two, as most people do. " When they walk over the surface of the Earth at a site they get a two-dimensional view," Rapp says. "Geologists are very good at that third dimension."

Beyond that, his methods are, relatively speaking, simplicity itself in these high-tech days.

He wants to know as much as possible about a site in advance from scholarship in the library. Then, he studies satellite photos of a prospective site for promising places to begin the actual process of discovery, which in his case involves drilling holes into the ground. Hundreds of holes. By hand. Which can take years.
But, he is quick to add, "I love it. I love that kind of work."

Basically it involves twisting a shovel-like device an infinite number of times to extract cores, or cylinders, of soil out of the ground at ever deeper intervals. At Huanbei Shang City "we knew when we were down at the right level," he explains, by what eventually came up in the core.

"In an inhabited site, there's a lot of extra rubbish and a lot of that rubbish is decomposed." he explains. "An ancient agricultural field is going to have one kind of deposit, a city is going to have another kind of deposit."

By coring over carefully plotted areas and examining the composition of the cores, it gradually becomes clearer where the city was, where the open fields were, and where the earthen walls that separated them were.

"Pretty soon, we defined outside of the city as opposed to inside of the city," he adds.

For a man with his record of significant finds, Rapp is pragmatic about his life's work, describing himself as a "stumbler" when it comes to archaeology. But in his case, the stumbling comes, for example, in landing opportunities such as the chance to search for the lost cities and shorelines. Or in finding a completely different "lost city" than the one you're searching for, as was the case with the Great City Song.

He got his start in archaeology in Greece as the result of a luncheon meeting with a colleague who led a Greek prehistory project who invited him to join the dig.

The balance of his career, Rapp says, shows that it is hard-headed pragmatism and a working knowledge of geology, not wide-eyed mysticism, that produces results in his chosen field.

Working years ago in Greece, for example, he deployed a magnetometer, which detects subtle differences in the chemical composition of soils, to search for buried city walls.

"In ancient Greece, walls were made of absolutely iron-free limestone rocks and they showed up dramatically compared to the iron in the surrounding soil," he said. "All it takes are a few iron atoms to make the difference."

No fan of the Indiana Jones films, despite the entreaties of his family to sit down and watch them, Rapp is emphatic that the field of archaeology has changed dramatically since the 1930's, when the films are primarily set—and even earlier days of archaeology—in favor of his methods.

It is science that will lead the way to new finds like the lost cities of China that are invisible to the naked eye. "A hundred years ago, or less, people could stumble through the South American jungle and stumble upon a lost temple," he says. "Not any more."

Back to News»