When Nicaragua's Momotombo volcano, which had been dormant since 1905, erupted on Nov. 30, 2015, Peter LaFemina saw a chance to investigate the volcano in more detail to better understand how and when volcanos erupt. He and two other Penn State researchers — Christelle Wauthier and Maureen Feineman, both assistant professors of geosciences — were awarded a grant for just over $40,000 from the National Science Foundation to closely monitor the volcano using a multifaceted approach to assess eruption progress and whether more eruptions might occur. They are working closely with Nicaraguan scientists and communities to provide information on the potential hazards of eruptions.
LaFemina, associate professor of geosciences in Penn State's College of Earth and Mineral Sciences, has been researching volcanism and plate tectonics in Nicaragua since 1994 — most recently investigating Telica volcano, another active volcano 31 miles (50 kilometers) from Momotombo. As part of his Telica project, he installed GPS monitoring equipment on Momotombo, and observed seismic activity at Momotombo 19 months before the November 2015 eruptions.
"On April 10, 2014, there was a magnitude 6 earthquake near Momotombo. During that event, we saw that Momotombo shifted by nearly 2.5 inches (6 centimeters). We later observed low-level seismic activity beneath Momotombo, which we now think was magma moving up through the earth's crust," said LaFemina.
Shortly after Momotombo erupted and expelled a lava flow, the Nicaraguan Institute of Territorial Studies requested that researchers from Penn State, the University of South Florida and the Carnegie Institution of Washington — all collaborating on active volcano research projects in Nicaragua — visit Momotombo to research and aid in the monitoring of the volcano. LaFemina quickly applied for a Rapid Response Research grant through NSF to install more monitoring devices on the volcano and sample the erupted lavas. Some of the equipment he and his colleagues installed will be donated to INETER once Momotombo is no longer active.
The team installed five GPS devices to track ground deformation around the volcano. Four new seismometers will help them better locate future earthquakes and track their frequency. Wauthier will be analyzing ground-surface-deformation maps created through a satellite-based radar geodetic technique, Interferometric Synthetic Aperture Radar. Feineman is investigating the composition of the lava and the minerals it carries to determine the origin of the magma that formed it — for example, at what depth in the earth's crust it may have been stored, and for how long, prior to erupting. In addition, the team is analyzing ground-based radar data, digital photographs and videos of the volcano.
"Each volcano we study has its own attitude and behavior," said LaFemina. "Prior to the magmatic eruption at Momotombo, there was a steady progression of seismic activity and decades of high-temperature degassing. In contrast, Telica has persistently high seismic activity that decreases prior to explosions, where no lava is erupted. Understanding those differences is powerful when you want to forecast eruptions and hazards."
The team continues to monitor both Momotombo and Telica, so that they can identify potential hazards, magma pathways and storage areas and eruptions and work with INETER to notify local communities if needed.
A'ndrea Elyse Messer