## 5 Primary Environmental Effects Induced by the 30 October 2020, Mw = 7.0, Samos Earthquake
### Permanent Surface Deformation
#### 5.1.1 Permanent Surface Deformation in the Northwestern Part of Samos  
The northwestern coastal part of Samos is disrupted by the NE-SW-striking and NW-dipping Karlovasi-Kallitheae active normal fault. This structure is responsible for intense relief, comprising large morphological discontinuities corresponding to abrupt and steep fault scarps composed mainly of marbles at small distances from the shoreline and narrow and limited beaches with sand and pebbles. At larger distances from the shoreline, the morphological features are also attributed to faults with the same geometry but a different activity class, as they are characterized as inactive [7]. Figure 7: Neotectonic map illustrating the sites of the detected primary environmental effects in Samos island triggered by the 30 October 2020, Mw = 7.0, earthquake. Details for the geological formations and faults in Figure 2.  
* Uplift at the Karlovasi vessel shelter  
Permanent coseismic uplift was detected at the Karlovasi vessel shelter located east of the Karlovasi port (Figures 7 and 8), at a distance of about 16 km southwest of the mainshock epicenter. The vessel shelter has quay walls with a total length of 295 m, which are protected from strong waves and currents with natural boulders emplaced in the exposed side of the vessel shelter. The detected uplift was imprinted not only on the concrete works of the vessel shelter, but also on the protection boulders (Figure 8). Based on field measurements, the amplitude of the permanent coseismic uplift in this site reached 24 cm. * Uplift at Akra coast  
The area of Akra, east of the Ayios Nikolaos church, is located at a distance of \(\sim\)17 km southwest of the earthquake's epicenter and 1.5 km west of the Karlovasi vessel shelter (Figures 7 and 9). This area is mainly composed of metamorphic formations and in particular of grey to black-grey marbles of the Kerketeas unit [5; 23; 24]. Recent deposits  
Figure 8: Permanent coseismic uplift was observed in the Karlovasi area (**a**). More specifically, in the Karlovasi vessel shelter located east of the Karlovasi port (**a**,**b**). The uplift reached 24 cm and was detected not only on the concrete works of the vessel shelter (**c**), but also on the protection boulders (**d**). are observed only along the narrow beach and within the beds of torrents flowing into the beach. A coseismic permanent uplift of 20 cm, which was imprinted on the marbles of the Kerketeas unit, was observed at that site (Figure 9). At the base of the marbles along the rocky coast, the uplift has exirpated intertidal biota (Figure 9). In contrast to the northern coastal alluvial zone of the Karlovasi basin, which has low preservation potential for primary earthquake environmental effects, the area west and southwest of the Karlovasi port constitutes areas with a rich record of previous uplifts attributed to historical earthquakes. The higher potential for the preservation of primary earthquake environmental effects in this area is strongly related to its geological structure, which comprises metamorphic rocks, mainly marble and schists, and results in imprinting of permanent coastal uplift in these formations [28]. Based on the interdisciplinary study on Holocene shorelines at the Akra site, [28] observed a well-preserved colony of vermetids that has built a thin reef capping slabs  
Figure 9: (**a**) Permanent cooseismic uplift in the area west of the Karlovasi vessel shelter, at the Akra and Pounta promontories. The uplift was imprinted on the coastal marbles of the Kerketeas unit at the Akra promontory (**b**–**e**) and at the Punta promontory (**f**,**g**). These locations have high potential for preservation of primary earthquake environmental effects due to their resistant lithology. Notches attributed to previous earthquakes are also observed at these sites (**d**–**g**). of beachrock up to a height of 50 cm above sea level. On the nearby rocks, remains of vermetids were found at a height of 0.6 m and 1.1 m above sea level (asl), on average, on coastal rocks.