Introduction
On October 30, 2020, a day that also brought seismic activity to the East Aegean islands, an earthquake epicenter near Samos was felt just off the coast 3. A strong Samos Earthquake of a significant scale erupted in the same year at Samos Island, significantly affecting local people and gaining interest in the academic world 4. This introduction, therefore, initiates a voyage to untangle the whys and how about the manifestation of this seismic event, peer into its outcomes, and finally, try to learn the more significant messages that describe it.
The Samos Earthquake, which occurred on October 30, 2020, was an earthquake event related to the seismic episode that originated in the position located near the eastern Aegean Sea in the way that it manifested ground-shaking effects throughout the island and in nearby areas, as shown in (Figure 1) 3. When we move into the satellite of this terrible event, it is essential to understand the geological background that enabled this earthquake. The global context is also characterized by a preliminary understanding of the region’s more significant tectonic dynamics, including the convergence of the Eurasian and African plates 5. Having done so, the underlying fault systems associated with the Samos earthquake would be analyzed, thus pointing out how complex geological processes resulted in this disaster.
However, the effects of the 2020 Samos Earthquake did not end with the shocks that followed the seismic activity, just as the catastrophe branded all locations affected. The characterization of tornadoes became structural destruction, frequent mortality, and devastation (Figure 2) 2. However, the social, economic, and environmental consequences that have followed from this disaster are crucial to understanding what it was all about. Observing the reaction mechanism undertaken by local authorities and international bodies reveals how communities deal with such natural occurrences 2.
It would be incorrect to state the importance of studying the 2020 Samos Earthquake only for practical purposes; on the contrary, the whole longitude of the Earthquake can be considered a mirror that allows understanding of many valuable things in the future 1. As much as we pass through all the avenues of this notable disaster, we intend to find patterns, finish up weaknesses, and build up a finished idea of the complexities related to universal catastrophes. To summarize the present knowledge and analyze the hypothesis critically through literature review techniques, we endeavor to contribute further to the ongoing conversation in earth sciences.
This report aims to thoroughly understand the pillars that the Earthquake caused in Samos in 2020, as well as the geological bases and possible after-effects. 1. By systematically investigating and critically appraising, we strive to formulate essential insights concerning nature’s disasters, their root causes, and their appropriate hedges and evasion. With this journey in mind, the 2020 Samos Earthquake acts as a clear reflection of the curvature of the Earth as a dynamic process and a need for scientific consistency in the event of such natural occurrences.
Background and Context
2.1 Historical context of seismic activity in the eastern Aegean region.
Within Samos Island different seismic activities have been recorded over the years, dating back to 200 BC. The first earthquake events had minimal effects, and the first catastrophic seismic activity was in 47AD, which had a magnitude of 7.0. These shared similarities with the most recent one in 20207. Historical reports of the region showcase how the nearby cities suffered damage since the epicenter could be located in nearby towns such as Izmir. Most of the information gathered from the Samos region depended on what was collected by local historians and was at least recorded by seismologists. One of the most destructive seismic events recorded was in 1688, when approximately 15,000 people died. The earthquake had a magnitude of 7.0. In the subsequent years, different events damaged the entire city, which illustrates how the place was wrong about earthquakes.
On 11th August 1904, the first seismic event with a magnitude of 6.8 occurred in the Aegen region. The earthquake was traced back to the Pythagorion fault in central Samos, and it resulted in damages to the settlement near the fault line7. Four people died as a result, while others were injured. In 1955, an earthquake occurred on the Samos coast, with a magnitude of 6.9, with heavy damage in Agathonisi, a nearby island south of Samos7. Most earthquakes had epicenters along the Samos coast, which shows that the Aegen region is seismically active. In the 21st century, there have been different earthquake events around the Greek and Aegen Sea regions.
Geological setting of Samos and its susceptibility to seismic events.
Samos is an island within the Aegen region in the eastern part of the Aegen Sea. This active tectonic region in the Euro-Mediterranean region has always been identified as a seismic hazard area. The area is surrounded by Eurasian, African, Arabian, and Anatolian plates, which undergo movements at different times, causing seismic activity8. The plate boundaries interact with each other either by subduction or forming a strike-slip fault. The African plates subduct against the Aegen plate, and in the process, this has resulted in earthquakes, which lead to tsunamis. The motion of the Anatolia plate and African plate in the northeast region of the Aegen Sea leads to extensional crustal deformation at a rate of 7.4 mm in a year, showing the settings of Samos8.
The setting makes it easy for Samos to be quickly affected by seismic events, considering how the plate movements gradually subduct, transform, and slip with time. Hellen Arc in the southern region of Greece and western Turkey is also a zone of seismic activity contributed by the Anatolian fault8. The usual fault somehow influences the Samos coastline since the striking between the Northeast and Northwest is striking8. Therefore, onshore and offshore faults contribute to tectonic activity within the region, making it susceptible to seismic events.
Figure 3: Eastern part of the Aegean Sea with the most significant earthquake5
Seismological Analysis
3.1 Investigation of the tectonic plate interactions that triggered the earthquake.
Samos earthquake was triggered by normal faulting due to the movement of the African plate in the northern direction in the eastern Aegen Sea. The African plate subducted beneath the Aegen and Anatolian plates, rupturing the normal fault that bounded the Samos basin8. Interaction of the African plates with the Anatolian and Aegen microplates caused tensional stress, w, resulting in the slab rollback that ruptured the north-dipping offshore fault. This was considered an intraplate earthquake since it involved different tectonic plates when they drifted. Dipping of the normal fault with an east-west striking triggered the earthquake at a shallow crustal depth as the African plate subducted at the Hellenic and Cyprus trenches7. This resulted in a potential earthquake of 6.8- 7.0 magnitude, as in the case of Samos Island.
3.2 Exploration of the magnitude, depth, and aftershocks associated with the event.
Samos earthquake was found to have a magnitude of 7.0, causing structural damage and loss of many lives across Samos1. The earthquake’s epicenter was located northeast 70km away from Samos, and this was at Izmir, which is a Turkish city. The earthquake lasted approximately 16 seconds and was the same as some of the historic seismic events within the same region. Samos earthquake achieved a peak ground acceleration of 0.27g, but this resulted in severe intensity in Samos, which was recorded to be VIII classified as severe3. The earthquake’s depth was 16.1 km, which describes how it is regarded as a shallow earthquake considering that it ranges between 0-70km deep. The aftershocks recorded between October and November of the same year were more than 2800, and this was after 39 foreshocks that preceded the Samos earthquake event9. The aftershock of the event was recorded in different locations across Greece and Turkey, with a magnitude ranging between 4 and 5.3.
Table 1: Characteristic parameters of the Samos earthquake8
Consequences and Impact
4.1 Immediate impact on Samos, Izmir, and surrounding areas.
The Samos 2020 earthquake had an immediate impact on the whole of the Samos area, and it had an extensive effect on Izmir, a Turkish city that was 70 km away northeast of Samos. The seismic event led to the death of two people at Samos, while at Izmir, more than 110 people succumbed due to the earthquake. Nineteen people were injured in Samos; on the other hand, 1,034 were nursing injuries due to the earthquake at Izmir1. The impact was more significant in Turkey than in Samos, Greece. There was substantial structural damage over Samos and the Turkish coast based on how the earthquake also caused a Tsunami. Seven hundred plus residential structures were destroyed, and boats were also washed away on the Greek and Turkish coasts as a result of the earthquake and tsunami9. It was approximated that 5,000 people were left homeless in the process, and the damages were upwards of $400 million in Turkey10.
The tsunami reached a height of 3.8 m, reaching 290m inland at Akarca, one of the municipalities of Izmir; for Samos, tsunamis reached 100 meters inland and had a height of 3.3m. The earthquake caused a tsunami, which made it great and worsened the aftermath of the seismic events6. Rescue operations took a lot of time as people were to be recovered from the collapsed and damaged buildings. Families and affected individuals had to set up tents to manage the disaster, as relief food was also being donated. Many families were affected, and they lacked a place to stay and a means of survival, especially in the Turkish region of Izmir.
Socio-economic repercussions.
Since many lives were lost and properties were damaged in Samos and Turkish coastal towns, there were severe socio-economic repercussions. Many businesses along the coast of Turkey were swept away by the tsunami or were lost after the buildings were destroyed. People lost their sources of income, affecting their socioeconomic lives because of how they depended on it2. Even other buildings that did not collapse but had cracks had to be damaged in the process, and this shows the effect of the seismic event based on how people lost their property in the process9. Survivors of the Samos earthquake were to start life with nothing after working their lives to own properties or set up businesses. People were now displaced and homeless as they tried to seek how they would develop once again.
Samos Archeological Museum was among the affected buildings, and some of its artifacts and sculptures were destroyed. The place had historical value, and this is an example of the extent of the damage. Education services were also affected since most schools were closed as rescue operations were ongoing. Mazi school was one of the affected since massive damage to the structures made the classes unsafe. Due to the earthquake, people had to donate and offer humanitarian responses to help the affected people. The government provided financial assistance to help in emergency response, as other foreign countries also sent rescue teams and provided medical and food aid to the affected people.
Comparative Analysis
5.1 Comparisons with other historical earthquakes
5.1.1 Similarities
The Samos 2020 earthquake shared similarities with other seismic events that had occurred prior. The event was similar to the recent Papua New Guinea seismic, shallow-depth earthquake in 201911. The two events share the same magnitude, resulting in significant damage within the area. Samos earthquake event is similar to the 2017 Bodrum-Kos earthquake in Turkey and Greece. It had substantial structural damage with a magnitude of 6.6, and several people lost their lives. Hebgen Lake earthquake, which occurred in 1959 and had a magnitude of 7.2, is also similar based on how it was caused by normal fault drifting tectonic plates, which is the same case as Samos 202012.
5.1.2 Differences
The Samos 2020 earthquake was similar to the Nepal Earth earthquake in 2015, with a magnitude of 7.8 and an intensity of X, showing its level of damage. The difference is in how the seismic event was catastrophic based on how more than eight thousand people lost their lives, and more than twenty thousand were injured13. The Great Japan earthquake in 2011 had a magnitude of 9.0 and was one of the most destructive seismic events. The quake was caused by the sliding of the Pacific plate beneath another plate, releasing great energy that killed more than 19,000 people14. This was different in terms of intensity, magnitude, and cause.
Regional and global implications of the 2020 Samos Earthquake.
Samos earthquake led to the regional corporation in terms of disaster management. Turkey and Greece had to work together to rescue the affected victims. Rescue teams worked together to save lives, showing how they had to gather resources to help affected areas15. The earthquake enabled Turkey and Greece to work with nations like America to address the earthquake problem. 16NASA, the Turkish Space Agency, and other institutions collaborated to give a seismic report of the affected region. The earthquake made it possible for neighboring countries within the Aegen Sea region to work and adapt new construction technology to avoid destruction in cases of earthquakes. Countries realized how destructive the quake can be, and thus needed to adapt to new construction methods to prevent damage and loss of lives.
Lessons Learned 300
6.1 Scientific insights gained from studying this earthquake.
Through the review of the Samos 2020 earthquake, much has been learned about how plate movements cause earthquakes. Plate movements play an essential role in earthquakes, making it possible to understand different plates and their movements regarding the Samos 2020 earthquake event. The seismic event has also made me realize how the movement of tectonic plates can release a significant amount of energy, which leads to earthquakes. The effect of an earthquake depends on the energy released and ground motion since events with greater magnitudes and intensity appear to be more catastrophic. With more intensity, a tsunami can quickly start and cause further destruction. Therefore, the science of tectonic plate plate movement drifting and causing earthquakes is an important insight gained from the Samos earthquake.
How the event contributes to understanding seismic hazards and risk mitigation.
The event makes it possible to understand how earthquakes incredibly lead to disasters, especially in areas where there are tectonic plate movements. From the seismic event, one can know how different earthquakes have implications for the socioeconomic activities of humans and cause potential harm to the environment. The destruction caused by earthquakes can seriously lead to the loss of many lives and the destruction of property and the environment, showing how dangerous they are as a natural disaster. This shows the importance of efficient disaster management, which would help rescue affected individuals and improve infrastructure building and construction. The event makes it possible to understand how important it is to be prepared, especially in regions considered seismically active5. Such areas should have mitigation strategies that can ensure lives are secured and properties are not damaged. The event shows the need for sound investment in emergency response to help if there is an earthquake event to help carry out rescue operations5.
Conclusions
In conclusion, the Samos 2020 earthquake was a significant natural disaster that occurred in Samos Island, located northeast of Greece. The quake was caused by the movement of the African, Aegen, and Eurasian plates, which caused normal faulting in the Eastern region of the Aegen Sea. The Earthquake had a magnitude of 7.0, with a depth of 16.1 km, and this resulted in more than 2,800 aftershocks as of November 2020. The earthquake led to the loss of more than 1,034 lives and the destruction of many properties within Samos and the Turkish city of Izmir. Many people lost their homes and businesses, and this affected their socio-economic lives. Through the event, it is important to note how tectonic plate movements can result in earthquakes of destructive magnitudes. Proper risk mitigation and disaster management strategies should be set up to help in cases such as the Samos earthquake.
References
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