Eisenhower Tunnel Sackungen
Eisenhower Tunnel sackung. Photo by David Varnes, USGS
Sackungen on the ridge above the tunnel could have misled geologists and engineers who were trying to predict where the tunnel boring might encounter fault zones. Sackungen were not well understood by American geologists at that time. It is possible that a sackung scarp might have been interpreted as a fault and projected to the depth of the tunnel bore. However, it is doubtful that a sackung would extend that deep into the mountain, thus possibly leading to confusion as to what features at the surface connected to features in the subsurface.