Assessment of seismically induced damage using LIDAR: The ancient city of Pınara (SW Turkey) as a case study

Abstract

Seismic-related damages of archaeological structures play an important role in increasing our knowledge about the timing and magnitudes of historical earthquakes. Although quantitative data should form the basis of objective archaeoseismological methods, most studies still do not rely on such methods. Ground-based LIDAR (light detection and ranging) is a promising, rather new, scanning technology that determines spatial position of an object or surface and provides high-resolution three-dimensional (3D) digital data. Using LIDAR, the damage and overall condition was mapped of a Roman theatre in the ancient Lycian city of Pınara (500 BC-900 AD0), located at a faulted margin of the Eşen Basin (SW Turkey). An average 0.81° NW tilt of the 20 seating rows could be computed from the LIDAR data. Conventional compass readings of these seating rows did not provide the same results because errors involved with this method are generally > 2°. The tilt direction appears perpendicular to the NE-trending basin-margin fault, suggesting that fault-block rotation is the most likely mechanism to have induced the systematic tilt of the theatre. The estimated 4 m offset on this normal fault should be seen as a rough estimate of the total displacement and was likely produced by several (more than one) earthquakes with magnitudes of M = 6-6.8. This is consistent with the historical records that mention several large earthquakes during the Roman period.

A high resolution laser scanning model of the Roman theater in Pinara, Turkey – comparison to previous measurements and search for the causes of damage

“…Examples where ancient buildings are proxies of levels instead of seismoscopes are dislocated aqueducts [11] and extended structures like amphitheaters [2]. In their study of the Pinara Roman theater, Yerli et al [2] used a terrestrial lidar system to construct a 3D virtual structure. The Yerli et al [2] model is composed of 5.5 million-points in a 3D cloud gathered with a distance resolution of 2.0 cm.…”

“…1) was to compare scan results with two independent systems, a pulse based lidar and a phase laser scanner, and test the hypothesis of coseismic inclination of the theater by Yerli et al [2]. In this contribution we:…”

“…In their study of the Pinara Roman theater, Yerli et al [2] used a terrestrial lidar system to construct a 3D virtual structure. The Yerli et al [2] model is composed of 5.5 million-points in a 3D cloud gathered with a distance resolution of 2.0 cm. From this model, the authors took measurements to test the theater for inclinations for which movements on nearby faults were cited as a possible explanation.…”

“…The archaeological site of Pinara in southwestern Turkey has been the target of several previous archaeoseismological studies [1][2][3]. The site, which includes a large number of objects of the cultural heritage from Lycian to Roman times, has been known since the first expeditions in the 18th century [4] but only described in detail for the first time by Wurster and Wörle [5].…”

Integrated detection and analysis of earthquake disaster information using airborne data

“…Numerous studies have focused on earthquake damage mapping using very high-resolution optical satellite remote sensing images (Vu et al 2005;Yamazaki et al 2005) and active remote sensing images such as synthetic aperture radar (SAR) (Dong et al 2011) and light detection and ranging (LiDAR) images (Yerli et al 2010). Despite continuous technical improvements, current space-based sensors may be unable to provide timely data because of adverse weather or long revisit periods.…”