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Frank Trusdell

Frank A. Trusdell is a research geologist at the U.S. Geological Survey's Hawaiian Volcano Observatory. 

Trusdell’s work has included a wide range of field-based studies and the production of detailed geologic maps of Mauna Loa, the largest active volcano in the world. To date he has completed four of five maps, each encompassing an area of Mauna Loa from its summit to sea level. These geologic maps provide information on the long-term eruptive behavior of the volcano. Trusdell also led the effort to create and publish lava inundation zone maps for Mauna Loa ( These nine maps, which identify parts of the volcano that could erupt and send lava flows downslope, provide information that will help emergency managers identify people, property, and facilities at risk during future Mauna Loa eruptions.