The Mediterranean Basin is characterized by a significant variability in tectonic behaviour, ranging from subsidence to uplifting. However, those coastal areas considered to be tectonically stable show coastal landforms at elevations consistent with eustatic and isostatic sea level change models. In particular, geomorphological indicators—such as tidal notches or shore platforms—are often used to define the tectonic stability of the Mediterranean coasts. We present the results of swim surveys in nine rocky coastal sectors in the central Mediterranean Sea using the Geoswim approach. The entire route was covered in 22 days for a total distance of 158.5 km. All surveyed sites are considered to have been tectonically stable since the last interglacial (Marine Isotope Stage 5.5 [MIS 5.5]), because related sea level markers fit well with sea level rise models. The analysis of visual observations and punctual measurements highlighted that, with respect to the total length of surveyed coast, the occurrence of tidal notches, shore platforms, and other indicators accounts for 85% of the modern coastline, and only 1% of the MIS 5.5 equivalent. Therefore, only 1% of the surveyed coast showed the presence of fossil markers of paleo sea levels above the datum. This significant difference is mainly attributable to erosion processes that did not allow the preservation of the geomorphic evidence of past sea level stands. In the end, our research method showed that the feasibility of applying such markers to define long-term tectonic behaviour is much higher in areas where pre-modern indicators have not been erased, such as at sites with hard bedrock previously covered by post-MIS 5.5 continental deposits, e.g., Sardinia, the Egadi Islands, Ansedonia, Gaeta, and Circeo. In general, the chances of finding such preserved indicators are very low.

中文翻译：

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现代和 MIS 5.5 侵蚀地貌和生物结构作为海平面标记的保护：运气问题？

地中海盆地的特征是构造行为的显着变化，从沉降到抬​​升。然而，那些被认为构造稳定的沿海地区在海拔高度上显示了沿海地貌，这与静静压和等静压海平面变化模型一致。特别是地貌指标——例如潮汐槽口或海岸平台——经常被用来定义地中海沿岸的构造稳定性。我们使用 Geoswim 方法展示了在地中海中部九个岩石海岸地区进行的游泳调查结果。全程22天，全程158.5公里。自上次间冰期（海洋同位素阶段 5.5 [MIS 5.5]）以来，所有调查地点都被认为是构造稳定的，因为相关的海平面标记与海平面上升模型非常吻合。目测和准点测量分析表明，相对于调查海岸的总长度，潮汐缺口、岸台等指标的出现占现代海岸线的85%，仅占MIS 5.5的1%。相等的。因此，只有 1% 的调查海岸显示在基准面上方存在古海平面的化石标记。这种显着差异主要是由于侵蚀过程不允许保存过去海平面的地貌证据。最后，我们的研究方法表明，在前现代指标尚未消除的地区，应用此类标记来定义长期构造行为的可行性要高得多，例如在以前被后 MIS 5.5 大陆沉积物覆盖的硬基岩地点，例如撒丁岛、埃加迪群岛、安塞多尼亚、加埃塔和 Circeo。一般而言，找到此类保留指标的机会非常低。