A story about beach parties — from the distant past.
Ronald Blom is a geologist at the Jet Propulsion Laboratory. A current project is using images taken from aircraft to help identify potential sites of Native American settlements on government land.
Blom and his colleagues hope to identify locations that have artifacts like tent foundations, baskets, burial sites, and trash heaps. They’re working at San Clemente, an island off the coast of Southern California that was inhabited by Native Americans from perhaps as far back as eight thousand years ago until the 1800s.
Dr. Blom doesn’t expect to see the actual settlements in the pictures. Instead, he wants to predict where the settlements are most likely to be, by looking at the island’s topography — the ups and downs of its surface. Topography is important because it determines where fresh water can be found and also the location of trash heaps — or middens — filled with cultural detail.
Ronald Blom: In the case of the island, one of the things the people apparently liked to do is get aways off the beach to have their seafood BBQ, because I think there were fewer flies and other obnoxious critters if you got on a ridge just a little bit up from the beach. That seems to be where the shell middens often are, although some are on the beach, so does vary.
Imagine how many clues about you are hidden in your trash! An archeologist could learn your favorite breakfast cereal, the length of your hair, and what size underwear you wear by going through your garbage heap. Burial sites are also extremely helpful to archeologists trying to reconstruct what an ancient culture believed to be important, explains Dr. Blom. But unlike trash heaps, burial sites are not always nearby settlements. Still, knowing where the location of a settlement can narrow down the region where one might expect to find a burial, he says.
Scientific research doesn’t always strike out into the unknown. San Clemente — which is owned and used by the U.S. Navy — has already been extensively studied, and yet Blom and his colleagues are taking many pictures of the island with aircraft. They plan to exhaustively map out Native American sites on the island that are already known and identify terrain and plants that are already extensively described.
Why bother to study something so well known? Sometimes, scientists use a well-known and well-understood object or place to test out new methods or techniques. San Clemente is a test case. Because the researchers know what is there and what to look for, they can compare the various different remote sensing methods. They can take pictures in different wavelengths of light , tweak the settings on the cameras, and make use of different measuring techniques — and then compare the strengths and weaknesses of each in picking out well-known targets. The plan is to figure out which method will be best for increasing the ability to quickly identify potential sites — and then use that method in other locations. In essence, the researchers are building a remote sensing toolkit for archeologists to use — and also putting together an instruction manual — or protocol — to help archaeologists apply the right tool in a given situation. Blom cautions that the new techniques won’t spot everything — but it should give a new tool to archeologists.