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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.

On 17 August 1999 the M w 7.5 İzmit, Turkey, earthquake produced surface rupture in excess of 120 km, and perhaps as much as 200 km, with up to 5 m of dextral slip, along a western portion of the North Anatolian fault zone. The 12 November 1999 M w 7.1 Düzce, Turkey, earthquake produced a 40-km-long surface rupture, including 9 km of rupture overlap with the eastern end of the August event. Our mapping focused on the 40-km-long Karadere rupture segment, the easternmost segment of the August event, as well as on the western 20 km of the November rupture. Maximum dextral slip along the Karadere segment is approximately 1.5 m, and the average slip on this segment is close to 1 m. Although slip along the Karadere segment is considerably less than that on segments to the west, this segment is of particular interest for three reasons: (1) the western boundary of the Karadere segment is defined by the most striking structural discontinuity along the entire August surface rupture (i.e., a 5-km-wide zone of no surface rupture, as well as a 25Њ change in trend from E-W to ENE), and such a discontinuity may have important implications for rupture dynamics; (2) surface rupture terminates at the east end of the Karadere rupture segment at a 1.5-to 3-km-wide extensional step-over at Eften Lake; and (3) the 12 November 1999 Düzce earthquake reruptured the easternmost 9 km of the Karadere segment, raising interesting questions about rupture dynamics and interactions between events on adjacent fault segments. The details of the 17 August 1999 and l2 November 1999 surface rupture traces suggest that rupture may have partially propagated across the Eften Lake extensional step-over, although this step-over seems to have acted as an effective barrier to rupture propagation.

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