Monitoring Erosion of a Submerged Stone Age Site and Its Implications for Managing Underwater Cultural Heritage. A Case Study at Tybrind Vig, Denmark

Known locations with submerged and well-preserved Stone Age sites in Denmark are, in most cases, under constant threat of erosion. The results presented here have been gathered at Tybrind Vig by surveying a 165 m-long transect at 5-metre intervals from the shore, by measurements taken with a total station. To supplement this, the surrounding area was surveyed with an echo sounder/sonar unit that yielded 3D coordinates post-processed in GIS to investigate volumetric changes in the seabed over time. The transect data was used to calibrate the elevation data from the echo sounder, following the correction of sea level change with data gathered from the Danish Coastal Authority. It was established that sediment transport – both erosion and accumulation – has occurred, but from the methods used, it cannot be determined how much of the archaeologically rich gyttja layers have been eroded at Tybrind Vig.