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1 Department of Geology, University of Bristol, Wills Memorial Building, Queen’s Road, Bristol BS8 1RJ, UK
2 Jeoloji Mühendisligi Bölümü, Mühendislik Mimarlik Fakültesi, Osmangazi University, Eskisehir, Turkey
3 Engineering Faculty, Mersin University, Ciftlik Koyu, Mersin, Turkey
4 Department of English, University of Bristol, 3-5 Woodland Road, Bristol BS8 1TB, UK
The presence of travertines adjacent to the city and their value for construction was well known to the Greek, Roman and Byzantine residents of Hierapolis (modern Pamukkale). The travertines were mainly extracted from quarries on the outer slopes of a low plateau below the city. The distinctive attribute of most of the quarries is that they are narrow but deep vertical-sided trenches. Each trench is the site of a nearly vertical fissure that was filled by banded fissure travertine, one type of so-called Phrygian marble. Trench walls, formerly the contacts between vertical banded travertines and outward dipping bedded travertines, bear a well-defined herringbone pattern of tool marks identical to those on many of the stone blocks that were used for building Hierapolis. Deposition of the travertines in 21 major fissure-ridges was a consequence of precipitation following degassing of carbonate-rich hot waters emerging from springs aligned along active faults and associated fissures. Whereas the dense and attractively banded travertine in fissures was principally used as an ornamental stone, the bedded travertines of ridge sides were mainly employed as a dimension stone and for making columns. After many of the monuments at Hierapolis had been constructed from travertine, itself a faulting-related material, some of them were subsequently destroyed or damaged by earthquake fault reactivation, which caused them to be either shaken or displaced. The zone of greatest seismic damage coincides with the trace of the Hierapolis fault zone, whose location was detected from an alignment of offsets of walls and petrified irrigation channels. The kinematic class of this fault zone could be deduced because offsets of the linear archaeological features permitted opening directions to be determined, thus allowing the fault zone to be reinterpreted as a normal fault zone achieving a small downthrow to the southwest. The knowledge that the Hierapolis fault zone is a structure across which there is active stretching and increased hydrothermal flow helps to explain why the present-day area of hot pools and travertine deposition is situated immediately downslope of the fault trace. If this relationship between displaced features and recent travertine deposits occurs elsewhere it might be employed for finding the locations of earthquake faults.
* Deceased, reprint requests should be addressed to A. Becher-Hancock.
