Liquefaction Phenomena Induced by the 26 November 2019, Mw = 6.4 Durrës (Albania) Earthquake and Liquefaction Susceptibility Assessment in the Affected Area

Abstract

On 26 November 2019, an Mw = 6.4 earthquake struck the central-western part of Albania. Its impact comprises secondary earthquake environmental effects (EEE) and severe building damage within the Periadriatic and the Tirana Depressions. EEE comprised mainly liquefaction phenomena in coastal, riverine, and lagoonal sites of the earthquake-affected area. From the evaluation of all available earthquake-related data, it is concluded that liquefaction sites are not randomly distributed within the affected area but are structurally and lithologically controlled. The affected areas are distributed within NW–SE striking zones formed in graben-like syncline areas with NW–SE trending fold axes. These graben-like areas are bounded by NW–SE striking marginal thrust faults and are filled with geological formations of Neogene to Quaternary age. These NW–SE striking zones and structures coincide with the NW–SE striking seismogenic thrust fault of the November 2019 earthquake as it is derived from the provided fault plane solutions. An approach for liquefaction susceptibility assessment is applied based on geological and seismological data and on liquefaction inventory. From the comparison of the compiled liquefaction inventory and the susceptibility maps, it is concluded that the majority of the observed liquefaction has been generated in very high and high susceptible areas.

Earthquake Environmental Effects and Building Properties Controlling Damage Caused by the 6 February 2023 Earthquakes in East Anatolia

“…Such areas are particularly vulnerable to the triggering of liquefaction phenomena, as has been demonstrated and highlighted in cases of other recent earthquakes in the Balkan Peninsula, where lateral spreading and sand boils have occurred in abandoned meanders and old riverbeds. Similar examples of liquefaction manifestations have been recently presented by Mavroulis et al [62] in the earthquake-affected area of Durrës (Albania) due to the 26 November 2019 Mw = 6.4 earthquake and by Papathanassiou et al [63] in the Pineios and Titarissios River beds due to the 2021 Thessaly (central Greece) Mw = 6.3 earthquake. In both cases, based mainly on field observations and mapping of the earthquake-triggered liquefaction phenomena, it is concluded that most of them were generated where river channels had been reclaimed or in abandoned and filled channels.…”

“…Additionally, scree is also presented in areas with a large slope along the mountain front [64]. Regarding hydrogeology, the area is characterized with a high groundwater level ranging from 0-6 m to 15 m or more [62]. From the active tectonics viewpoint, the residential area of the Ahir Mt front is disrupted by E-W striking faults that have produced surface ruptures during the last 11,000 years, while the northern boundary of the city has also been disrupted by faults that are suspicious for Holocene activity [14] (Figure 20).…”

The 26 November 2019 Durrës earthquake, Albania: coseismic displacements and occurrence of slow slip events in the year following the earthquake

“…During the last two decades, several moderate earthquakes M > 5.0 have hit Durrës, mentioning the 5 September 2007 (4.8-5.0) and the 4 July 2018 (M w 5.1) earthquakes. The last seismic activity, resulting in the strongest instrumental recorded seismic activity during the last four decades in this region, started on 21 September 2019 (M w 5.6), located 3-km west of Shijak, subsequently followed, after 10 min, by an M w 5.1 aftershock (Figs 2 and 3;Aliaj 2020;Papadopoulos et al 2020;Mavroulis et al 2021;Anton et al 2022). The main shock and seismic sequence aftermath caused severe damage to local building environments.…”

Seismic Liquefaction Resistance Based on Strain Energy Concept Considering Fine Content Value Effect and Performance Parametric Sensitivity Analysis

“…The 1964 magnitude 9.2 earthquake in Alaska and the magnitude 7.6 earthquake in Niigata of the same year, prompted extensive research on this phenomenon. Soil liquefaction has also been observed in recent earthquakes in China [1], Japan [2], Indonesia [3] and the USA [4,5].…”