Earthquake Mb 4.6 Shakes Volcano Region Near Awash in Ethiopia – Ground Uplift Detected
On the evening of October 16, a magnitude 4.6 earthquake occurred in the Awash region of Ethiopia near the Fentale volcano, and it was also felt in Addis Ababa. With a depth of about 10 kilometers, the earthquake may have been shallower, as the seismological monitoring in the region is imprecise. For weeks, numerous smaller tremors have been damaging infrastructure such as railways and buildings.
InSAR data shows a possible ground uplift of up to 30 centimeters, indicating magma intrusion close to Fentale volcano. Previous studies have shown that rhyolitic magma intrusions have occurred here before, which is unusual in this basalt-rich region. These intrusions were accompanied by strong earthquake swarms, similar to what is happening now. However, it is possible that the InSAR image reflects other effects, such as a high water level on the Awash River.
The Fentale volcano, dominated by a 5-kilometer-wide caldera, is both effusive and explosive, unlike most other volcanoes in the region. The tectonic activity is driven by the divergent boundary between the Somali Microplate and the African Plate. A phreatic eruption occurred last week in a thermal area near the volcano. It is possible that a volcanic eruption may follow.