Rapid response provides window into ongoing Kīlauea eruption
This image is generated by elastic scattering of the electrons in the EMP beam by atoms in the sample. The grayscale value of each pixel in the image is a consequence of the composition of the material with which the beam interacts. The small crystals of plagioclase and larger crystals of olivine in this sample are typical of lava from Kilauea. The 100 micron scale bar at lower right is equal to 1/10 mm. Credit: UH SOEST Electron Microprobe Lab.
Lava eruptions continue in Halemaʻumaʻu crater at the summit of Kīlauea Volcano on Hawai‘i Island. On the evening of December 20, an eruption began within Kīlauea’s summit caldera and the water lake boiled away with an effusive eruption.
Julia Hammer and Thomas Shea, Earth Sciences professors at the University of Hawai‘i at Mānoa School of Ocean and Earth Science and Technology (SOEST) led a rapid response effort to analyze fresh samples of Kīlauea lava in the Electron Microprobe (EMP) Laboratory.
In coordination with the U.S. Geological Survey’s Hawaiian Volcano Observatory (HVO) and the University of Hawai‘i (UH) Hilo, the EMP Lab team, including graduate student Adrien Mourey, received five samples with glassy particles ejected from the summit crater during lava fountaining on December 20 and 21.
Using advanced analytical techniques and expertise, the team determined the textures and the chemical compositions of glassy ash particles, crystals, and Pele’s hair in an effort to better understand the start of the recent eruption.
“The chemical and physical characteristics of the lava are important for evaluating whether magma recently arrived from depth, that is from Earth’s mantle, or was stored inside the volcano since the last eruption in 2018,” said Hammer. “This information, combined with geophysical measurements, geological mapping, gas monitoring, and data from other sensors, helps scientists track the current activity and understand its place in Kīlauea’s overall pattern of recent eruptions.”
The lava samples were collected from trays and buckets set at the edge of Halemaʻumaʻu crater by HVO geologists for that purpose. Once they arrived at UH Mānoa, the delicate samples were mounted in epoxy, polished to a mirror-smooth finish, and analyzed with the EMP over two days.
Hammer and Shea were able to provide information to HVO and UH Hilo scientists within about a week after the magma erupted. Insights from such freshly erupted volcanic materials offers clues about the processes deep within the volcano that influence its eruptive behavior.
Specialized technology reveals finest detail
The EMP is housed within SOEST’s Earth Sciences Department and is part of a group of state-of-the-art specialized analytical equipment used to characterize the chemical and physical properties of natural and synthetic materials. A high voltage beam of electrons generated within the EMP is focused onto the sample surface. Detectors capture x-rays and electrons generated within the sample to create images at high magnification and to determine the elemental makeup of materials from Earth, the Moon, and other parts of the Solar System.