The 12th century seismic paroxysmin the Middle East: a historical perspective

The Dead Sea Fault and its junction with the southern segment of the East Anatolian fault zone, despite their high tectonic activity have been relatively quiescent in the last two centuries. Historical evidence, however, shows that in the 12th century these faults ruptured producing the large earthquakes of 1114, 1138, 1157 and 1170. This paroxysm occurred during one of the best-documented periods for which we have both Occidental and Arab chronicles, and shows that the activity of the 20th century, which is low, is definitely not a reliable guide to the activity over a longer period. The article is written for this Workshop Proceedings with the archaeoseismologist, and in particular with the seismophile historian in mind. It aims primarily at putting on record what is known about the seismicity of the region in the 12th century, describe the problems associated with the interpretation of macroseismic data, their limitations and misuse, and assess their completeness, rather than answer in detail questions regarding the tectonics and seismic hazard of the region, which will be dealt with elsewhere on a regional basis.