Understanding Volcanic Tremors and Their Role in Eruption Prediction

Volcanic activity is a complex natural phenomenon that requires a precise understanding of magma and gas movements within the Earth. By studying volcanic tremors, scientists can gain new insights into how volcanoes behave, potentially improving future eruption predictions.

The Role of Tremors in Volcano Studies

As magma moves from deep within the Earth, it can cause vibrations in the Earth’s crust. Under high pressure, magma may crack surrounding rocks, leading to earthquakes. However, there is another type of continuous, weaker vibration known as tremors, which occur when magma pushes through existing pathways, gas bubbles escape, or pressure fluctuates within volcanic channels.

Studying these signals and the types of waves generated by magma movement beneath the surface is crucial in volcanic seismology. This research provides scientists with a deeper understanding of the internal workings of volcanoes and the level of activity occurring within them.

Research by the Ries Team at Ol Doinyo Lengai Volcano

Researcher Ries and her team focused on monitoring the Ol Doinyo Lengai volcano for 18 months using an array of seismometers placed around the volcano to record ground vibrations. After returning to Mainz, the team meticulously analyzed nine weeks of data.

For the first time, the researchers were able to pinpoint the exact location of the tremors. They discovered two types of tremors that appeared to be connected: one originating at a depth of about five kilometers and the other near the volcano’s base, with a time delay between them. It was clear that these signals were linked, indicating a directly connected system.

Challenges of Carbonatite Volcanoes

The Ol Doinyo Lengai volcano is unique as it is the only active volcano in the world that produces carbonatite magma. This magma is characterized by its unusual fluidity and relative coolness, with temperatures around 550 degrees Celsius, compared to 650 to 1200 degrees for most other magmas.

The findings were particularly surprising because the magma was highly fluid. Researchers expected little to no tremors due to weaker interactions with the surrounding rocks.

Advancements in Volcanic Seismology

The results from the Ries team represent a significant step forward in understanding how magma moves within volcanoes. “Tremors occur whenever magma moves – including before an eruption,” Ries explained. “But which tremor signals are truly precursors to an eruption, and which are merely background ‘gurgling’? Our findings lay the groundwork for improving eruption predictions in the future.”

Conclusion

The study of volcanic tremors offers valuable insights into volcanic seismology, helping scientists better understand magma and gas movements within volcanoes. Through the research conducted by Ries and her team, they were able to accurately locate tremor sites and understand their connection to volcanic activity. These steps form the basis for advancements in improving volcanic eruption predictions, contributing to risk reduction and saving lives.