A new paper has been published online first by Hinzen et al. on their archeoseismological study in Cologne, Germany. During recent archeological excavations, a number of damaged structures from Roman to Medieval times have been discovered and described among them a synagoge, the Praetorium, and a Roman well. Since damaging historical earthquakes are documented for the Lower Rhine Embayment, seismic shaking was a good guess to have caused the observed damage. The authors conducted LiDAR scans, structural mapping, and ground motion modelling in order to find out whether the damage is related to an earthquake or to other effects like ground settling, natural deteriotation, flooding events of the nearby Rhine River, subsuface erosion or anthropogenic influence (e.g., WWII bombs). It turned out that an earthquake is only the second most likely cause and that most of the damage seems to be rather caused by subsurface erosion.
Hinzen, K.-G., Schreiber, S., Fleischer, C., Reamer, S.K., Wiosna, I. 2012. Archeoseismic study of damage in Roman and Medieval structures in the center of Cologne, Germany. J Seismol. DOI:10.1007/s10950-012-9327-2. open access!!!
Klaus Reicherter | 2012-10-22|10:14 (UTC)
I have never seen subsurface erosion causing large-scale liquefaction, has anyone an (published) example for that? Also, WWII bombs causing liquefaction in 8 m depth, has anyone a reference for me? Thank you, K.
Christoph | 2012-10-23|09:05 (UTC)
I guess some info can be found here, but I’ve no access to the journal: Crosta G, di Prisco C (1999) On slope instability induced by
seepage erosion. Can Geotech J 36:1056–1073 (http://www.nrcresearchpress.com/doi/abs/10.1139/t99-062#.UIZdwmcmZ8F)