GMS Juniors Field Trip

GMS Juniors Field Trip
Meteorite Impact Basin in Tennessee
Saturday, March 15, 2014

The special Juniors’ field trip to the impact site in Tennessee was a wonderful experience for all! Once again we dodged some unpleasant weather before and after the trip and were treated to a beautiful day that was perfect for collecting shatter cones.

GMS juniors and Meteorite Association of Georgia members gathered around as a Tennessee geologist explained what we would be seeing that day. Using detailed handouts and a large topological map of the crater, he pointed out features from where we were standing. From his descriptions plus a tour of the impact site to see geological anomalies directly attributed to the impact event, we learned how massive this ancient impact truly was. We saw shale that was way out of place for its age and tilted in a geologically odd way as well as some megabreccia completely out of place. We saw how a sheer bluff had layers tilted almost vertically on one side to partially tilted in the middle to almost horizontally tilted on the other side, all within yards of each other.

Each anomaly brought us closer to ground zero. We could see very clearly how the center of the impact had lifted rock from deep down up to levels that confused early geologists. At first they thought it might be volcanic activity, but that theory did not make sense considering the sedimentary nature of the rock. Careful mapping of the area along with detailed analysis of the anomalies helped confirm the impact. Topo maps of the basin show radiating faults from the center of the impact and the shape of the crater is unmistakable.

At ground zero we scrambled over rocks that exhibit the classic shatter pattern. It didn’t take long before everybody had excellent samples of shatter cones. The Nims found a stunning little snake that beguiled us all. It was such a gorgeous day and the collecting was so fun and exciting that we hardly wanted to leave, but there was one more surprise awaiting us.

We went to a super-secret location and collected beautiful blue slag! There was an iron furnace nearby and with some skillful sleuthing and avoidance of ticks, we believe we found the remnants of the furnace. Slag was everywhere and the prettiest blues, greens, and aquas were abundant. After we loaded up on slag we stopped by a local gas station where we were given permission to use Charles’ portable cabbing unit to face polish a few slag specimens. The manager at the gas station was very curious to see what we were doing and received a nice, custom wrapped pendant for his hospitality.

Again we must thank our geologist friend for another fun and educational trip!

Lori Carter, on behalf of
Charles Carter, GMS Field Trip Chair
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Click here for the March 2013 trip report
Click here for the July 2013 trip report