Wednesday, July 20, 2016

Exploring the Sand Bar

Erika and I setting up the Theodolite
 (Photo Credit: Genna Perry)

Hey everyone, I'm Austin George. Gary and I were students in the field school last year. This year, however, Gary is the Field Assistant and I am currently serving as the Lab Supervisor. This morning, I'm here to tell you about an interesting opportunity that we recently took advantage of. That is to say, when we arrived at the site yesterday, we discovered that the St. Joseph River was at an all-time low, or at least low enough for us to investigate an interesting magnetic anomaly that appeared on a geophysical survey conducted over the frozen river a few years ago by the Department of Geosciences at WMU.   
In order to conduct this investigation before the river reclaimed the sandbar, we canoed out onto the sand bar and marked the anomaly's exact location (87 North 37 West) using our electronic surveying equipment (the theodolite). We had Erika, the Teaching Assistant for the field school this year, stand on dry land with the actual theodolite while we took the prism, a pole for the theodolite to pick up on in order to identify the location on the invisible grid of the site, out onto the sandbar. This way she could be at a point on the grid that we have shot from before in order to pick up on our precise location.
While getting out of the canoe, we realized that this sand bar wasn’t really a sand bar because the mud went up past our ankles and we sank into it a little ways. After marking the spot with the prism, Gary and I then, systematically, probed around in the mud with five-foot metal rods until we hit something deep in the ground. We went several meters from our original point in hopes of getting a couple hits. While Gary continued to stick to the system, I decided to start going in bigger circles to try and find something, because we weren't getting any hits. Finally, after almost an hour of probing around, Gary called me over and showed me that he had a couple of strong hits. However, due to the artifact's depth and the muddy conditions, we were unable to determine what was beneath the surface. We concluded that there might be something there, but it was definitely deeper than we could go with either of our rods. Soon after we left the sand bar the river rose back up and reclaimed the area that we had just been probing on.

Gary and I on the sand bar (Photo Credit: Genna Perry)
Interestingly, there is a rumor in Niles that a cannon sunk in the river many years ago. They say that kids used to jump off of the cannon into the river, but for now those are just oral stories passed down to us through the locals of Niles. Wouldn't it be nifty if the magnetic anomaly we investigated on the sand bar was actually the legendary cannon? 

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