Abstract A historical earthquake-related co-seismic deformation observed on beachrock beds along the southern shoreline of Lake Iznik is discussed as a new paleoseismic record for an 8th century AD earthquake in the Middle Strand of the North Anatolian Fault, NW Turkey. Electrical Resistivity Tomography (ERT) images beneath the beachrock surface allowed monitoring of the subsurface trace of a normal fault dipping north along a 100 m surface rupture. No strike-slip deformation exists along the rupture, suggesting that the deformation in the beachrock is connected with a secondary structure, and that the main surface rupture was under the lake waters. The deformed beds of the beachrock, dated using Optically Stimulated Luminescence (OSL) to 1.3 ± 0.15 ka, are overlain by an undeformed secondary deposition of beds dated to 1.2 ± 0.09 ka. This allows us to narrow down the time of the faulting and implying that it was most likely a result of the AD 715 earthquake.

中文翻译：

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土耳其西北部伊兹尼克湖北安纳托利亚断层中链公元 8 世纪地震的同震海滩岩变形

摘要 讨论了在伊兹尼克湖南部海岸线的海滩岩床上观察到的历史地震相关的同震变形，作为公元 8 世纪土耳其西北安纳托利亚断层中链地震的新古地震记录。海滩岩石表面下方的电阻率层析成像 (ERT) 图像允许监测沿 100 m 表面破裂向北倾斜的正常断层的地下痕迹。沿断裂不存在走滑变形，说明滩岩变形与二级构造有关，主面断裂位于湖水下方。使用光激发光 (OSL) 测年为 1.3 ± 0.15 ka 的海滩岩变形床被测年为 1.2 ± 0.09 ka 的未变形次生沉积层覆盖。