Magma influx triggers temporary bulge at Tanzania's Ol Doinyo Lengai volcano

In 2024, a research team led by D. Sarah Stamps detected a brief, localized bulge of land around a volcano in Tanzania, marking the first time a short‑lived surface uplift has been linked to a sudden influx of magma in the region. The bulge, observed through satellite interferometry and ground‑based GPS monitoring, spanned several kilometers and lasted only a few weeks before subsiding.

Stamps’ subsequent paper, published on September 18, attributes the uplift to the injection of approximately one million cubic meters of magma into an existing reservoir located roughly 1.8 miles (2.9 kilometers) beneath the volcano’s summit. The study details how the rapid pressurization of the reservoir displaced the overlying crust, producing the observed surface deformation. By correlating the timing of the bulge with seismicity and thermal anomalies, the team demonstrates a clear causal relationship between magma movement and ground deformation.

The findings provide valuable insight into the plumbing systems of Tanzanian volcanoes and underscore the importance of continuous monitoring for early detection of eruptive precursors. Stamps’ work lays a foundation for future investigations into magma dynamics at depth, offering a more precise framework for assessing volcanic hazards in the region.