AVO, USGS, and Alaska Tephra Lab geologist Kristi Wallace hand selects clasts from tephra fallout samples collected at Akutan. These samples will be analyzed by x-ray fluorescence (XRF) and inductively coupled plasma mass spectrometry (ICP-MS) to determine their chemical composition. Geochemical data from these samples will help AVO understand the composition of the magmas that generated eruptions at Akutan over the last 10,000 years and will also help link the tephra to other eruptive products, including lava, mudflow, and pyroclastic flow deposits of specific eruptions. Photo by Cheryl Cameron, DGGS/AVO, May 13, 2015.
Credit: Image courtesy of the AVO/ADGGS.