Ethiopia experiences earthquakes and volcanic eruptions due to its location in the Great Rift Valley, a geologically active region. Recent tremors have prompted evacuations and raised concerns about eruptions. Tectonic processes, driven by molten rock movements, lead to ground separation and earthquakes. Improved monitoring and community engagement are necessary for hazard mitigation.
A recent swarm of earthquakes and concerns over potential volcanic eruptions in January have prompted the evacuation of tens of thousands from Awash Fentale, located in Ethiopia’s Afar region. This area is part of the Great Rift Valley, a geologically active region noted for numerous earthquakes and volcanic activities over the past 800 years, including significant eruptions in 1250 and 1820 AD.
The geological processes occurring in Fentale are the result of millions of years of evolution beneath the Earth’s surface. Scientists view the region as a natural laboratory, predicting a north-south continental division that will eventually lead to a new ocean at the East African Rift Valley. Gemechu Bedassa Teferi, a researcher focusing on the Main Ethiopian Rift volcanoes, sheds light on the causes behind these geological phenomena.
The tectonic activity in Ethiopia can be traced back eighteen million years when the continents separated, giving rise to the Red Sea and the Gulf of Aden. Approximately eleven million years ago, a fissure developed beneath the Afar Depression, situating it above the semisolid mantle layer that drives geological activities. The movement of this hot mantle material allows molten rock to rise through weaknesses in the Earth’s crust, causing volcanic eruptions.
Simultaneously, the rising molten rock contributes to ground separation, creating rifts filled by hot rock. This results in the sudden fracturing of nearby rocks and the release of energy, causing seismic waves that lead to earthquakes. The Afar region is recognized as one of the world’s most tectonically and volcanically active locales.
Recent events have not included volcanic eruptions; however, over 200 earthquakes have been recorded in the past five months, with the strongest measuring 6 on the Richter scale. The tremors damaged numerous structures and were felt as far away as Addis Ababa, nearly 190 kilometers from the epicenter. An earthquake of 6.5 on the Richter scale in 1989 marked the most powerful quake in the region since 1900.
Historically, an earthquake can precede volcanic eruptions, raising concerns that recent seismic activity might trigger eruptions at two nearby active volcanoes. Satellite radar has indicated that these earthquakes stem from hot molten rock rising from approximately 10 kilometers below Awash Fentale.
Several scenarios could develop following this geological activity. The first possibility is that the molten rock cools, leading to solidification. Alternatively, it may force its way to the surface, resulting in an eruption. Lastly, the molten material could interact with surrounding rocks laterally, possibly resulting in either cooling or significant volcanic activity.
Given the unpredictable nature of these geologic processes, improved monitoring and predictive methods are essential for hazard mitigation. Scientists advocate utilizing techniques such as volcanic gas analysis, onsite GPS monitoring, and comprehensive geophysical studies. Additionally, collaboration between scientists and government entities is crucial for establishing effective communication with communities at risk.
In conclusion, Ethiopia’s earthquakes and potential volcanic eruptions are the products of ongoing tectonic processes rooted in its geological history. With a proactive approach to monitoring these activities and engaging at-risk communities, scientists can work towards mitigating the hazards associated with this dynamic region. Understanding the underlying mechanisms is key to predicting future events and ensuring public safety.
Original Source: theconversation.com
