It’s been a busy week at the Issyk Kul project, and it’s time to share with you an update on what we’re up to! One of our biggest tasks this season is to get a handle on how big of a site we’re dealing with, which will help us in identifying this “building” or “buildings”—if that’s indeed what they are—and the significance of the site. These don’t involve the sexy moments of major discovery you see on TV, but they’re the critical first steps that we archaeologists have to take in order to achieve the big discoveries.
Although we’re looking at underwater remains, we can use many of the same basic survey approaches that are used on land. Right now, we’re busy running lines to create a map of the site. First, we establish an arbitrary “zero” line to divide the area we’re surveying roughly in half and identify its position using GPS. Then we run 50m-long ropes and tape measures spaced at 3m intervals north and south of this line. We swim the length of these lines while describing the geography of the lake bottom and marking the location of important features on our dive slates. All of these notes are then transferred to a computer program that helps us get a better overall view of the site.
Though it sounds pretty straightforward, running lines takes a lot of prep work. Every line needs to be anchored, so we have to salvage scrapped iron rebar from around our camp and cut it to size. Depending on the area, we may be working in 30cm of water (using snorkels) or 4m of water (with scuba tanks), and all of the rebar needs to be hammered into the lake bottom, whether it’s into loose sand or hard rock. The line is secured to the rebar, then swum out following a specific compass heading and anchored again at the other end. Only then can we document each line with written descriptions, photo and video.
On top of that, we’re busy documenting all of the very important features, such as potential walls, with a handheld GPS and plotting the points on our digital map to see if any consistent patterns appear. And we’re doing all of this while wearing heavy wetsuits and lead weight belts (for stability) in sometimes rough and blustery weather conditions, which means we’re definitely moving a lot slower than we would on land. Then there’s also the time factor of setting up and loading the boat with dive gear and tools and getting to and from the site, as well as wrestling with locally sourced measuring tapes that seem to have a lifespan of about three days in the salty waters of Issyk Kul.
While there’s plenty to see on the bottom with our masks, we suspect that there’s other archaeological material that may be buried under a meter or more of lake sediment. That’s where we rely on Alan, our engineer, who has been managing the remote-sensing work at the site. He’s using a boat-mounted sub-bottom profiler, which sends pulses of acoustic energy into the lake bottom. The echoes of these pulses are transmitted back to the profiler, and the variations in the intensity of these echoes can indicate buried structures that may tie-in to the visible features of the site.
So whether it’s high-tech remote sensing or good old visual surveying, we’re busy every morning and afternoon at Issyk Kul. It’s hard work, but it’s a fascinating site in a beautiful place!
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Want to chat with us live in the field? Our director Fred Hiebert will be answering questions in a Reddit IAmA session on Thursday, September 20 at 11am ET, and we’ll also be live from Issyk Kul in a Google+ Hangout at 9pm ET on Tuesday, September 25. Please log on and say hi!