Emplacement of the 1907 Mauna Loa basalt flow as derived from precision topography and satellite imaging

Abstract

An eruption in January of 1907, from the southwest rift zone of Mauna Loa, produced a substantial lava flow field. Satellite images and Differential Global Positioning System (DGPS) survey data, along with observations and photographs from the field, are combined to provide a new perspective on the 1907 eruption. Boundaries of the flow field from the satellite data, combined with field measurements of flow thickness, indicate an area of 25.1 km 2 and a volume of 86.6 million m 3. The eastern lobe of the flow field covers an area of 13.1 km 2, with a volume of 55.0 million m 3, and was emplaced with an average effusion rate of 119 m 3/s (at least, for the upper portion of the lobe). Ten DGPS topographic profiles across the eastern lobe aid in distinguishing the characteristics of, and transitions between, the zones identified during the emplacement of the 1984 Mauna Loa flow. Several subdivisions have been built directly on top of or adjacent to the 1907 lava flow. The strong likelihood of future eruptions from the Mauna Loa southwest rift zone makes these housing developments of particular importance for assessments of potential volcanic hazards.