Exploring Ethiopia’s Earthquakes and Volcanoes: A Geological…

The Afar region in Ethiopia experiences significant geological activity characterized by earthquakes and potential volcanic eruptions. Recent seismic events have prompted evacuations and are part of a long-term process tied to the geological evolution of the Great Rift Valley. Understanding these phenomena is critical for predicting future activity and ensuring community safety.

In January, a series of earthquakes and fears of volcanic eruptions prompted the evacuation of tens of thousands from Awash Fentale in Ethiopia’s Afar region. This area lies within the geologically active Great Rift Valley, which has experienced significant seismic and volcanic activity over the past 800 years, with notable eruptions occurring in 1250 and 1820 AD.

The ongoing geological processes in Fentale are the result of millions of years of tectonic activity, predicted to culminate in a continental split that could form a new ocean. Gemechu Bedassa Teferi, a researcher focusing on the Main Ethiopian Rift’s volcanoes, provides insight into the factors causing these recent seismic events.

Eighteen million years ago, the continents fractured, leading to the formation of the Red Sea and Gulf of Aden. Approximately 11 million years ago, a crack materialized beneath the Afar Depression in northeastern Ethiopia. The region exists atop a dynamic, semi-solid mantle layer, which is driven by geothermal heat, resulting in molten rock being pushed upward through the Earth’s crust, causing volcanic eruptions.

Additionally, as this molten rock rises, the crust begins to pull apart, creating rifts that may lead to earthquakes when the tension finally causes rocks to break suddenly. The Afar region is one of the most active volcanic and tectonic areas in the world, manifesting in disturbances such as those presently observed in Fentale and the northern Dofan region.

In the past five months, over 200 earthquakes, including a peak magnitude of 6 on the Richter scale, have been recorded, impacting infrastructure across a wide area, including Addis Ababa, located nearly 190 kilometers away from the epicenter. The strongest earthquake historically recorded in Ethiopia occurred in 1989, measuring 6.5.

The last eruption at Fentale occurred in 1820, and as past trends indicate, earthquakes often precede volcanic activity, raising concerns about the potential for eruptions at two neighboring active volcanoes. Satellite imaging has shown that the recent seismic activity in Fentale results from hot molten rock approximately 10 kilometers below the surface.

Several outcomes could develop from this ongoing geological activity, contingent on factors such as temperature and viscosity of the molten rock and the strength of surrounding materials. The cooling of the molten rock may occur, or it could force an eruption by rising directly to the surface or moving laterally. Furthermore, hot molten rock might interact with other materials, potentially leading to an eruption or cooling.

Given the unpredictable nature of these geological processes, there is a critical need for enhanced predictive measures. Employing techniques such as volcanic gas monitoring, GPS tracking, and geophysical surveys will be essential. Collaborative efforts involving scientists and government officials are vital in establishing communication channels to inform and safeguard affected communities.

In summary, the Afar region of Ethiopia is situated in a geologically active area of the Great Rift Valley, leading to frequent earthquakes and potential volcanic eruptions. Recent seismic events have resulted from deep subterranean processes involving molten rock shifting within the Earth’s crust. Understanding these dynamics is vital for predicting future volcanic activity and protecting the local population through improved monitoring and communication efforts.

Original Source: theconversation.com