Annual Kīlauea GPS Survey—2021

Over the past few months, HVO geophysicists have been conducting the annual high-precision Global Positioning System (GPS) survey of Kīlauea. The annual survey supplements HVO's continuous GPS monitoring stations and provides information on vertical and horizontal deformation of the ground surface. These measurements inform HVO about Kīlauea south flank movement as well as volume changes within subsurface magma reservoirs. Many of the survey locations are remote and accessible only via helicopter. This survey location was located on Kīlauea's East Rift Zone. USGS photo by A. Ellis.