For more information on how electronic tiltmeters and GPS receivers help monitor the deformation of Kīlauea volcano, see the HVO Deformation page.
Electronic Tiltmeters
Electronic tiltmeters are used by the USGS Hawaiian Volcano Observatory to monitor small changes in local ground surface orientation relative to gravity.
- Click image at right for larger map. Data plots from additional stations are available from our interactive map, which allows you to view different types of data (using the right-side menu on the map).
- Station UWD is located near Uēkahuna, on the western rim of Kīlauea's summit caldera.
- Station POC is located on the north rim of Pu‘u‘ō‘ō cone on the middle East Rift Zone of Kīlauea.
In the plots below, the different colored lines show continuously operating electronic tiltmeter measurements made in a specific direction at a specific station, (see the legend in the upper left corner of each plot). The blue line shows radial tilt measurements which record changes perpendicular to surface-normal, and the green line shows tangential tilt measurements that record relative changes parallel to surface-normal. Positive changes in tilt near volcanoes often indicate inflation of the magma storage beneath the caldera or on the middle East Rift Zone of Kīlauea, but may also result from heavy rainfall or, occasionally, instrumental malfunctions. To optimize displaying maximum magnitudes of deformation at each station, tilt azimuths, (which range from 0-360 degrees), are determined based on current geophysical conditions and may need to be occasionally updated due to changes in activity. Tilt azimuth for UWD plots were last updated from 320 to 300 degrees on July 9, 2025. Visit the HVO Deformation webpage to learn more.
On July 9, 2025, tilt azimuths for SDH and UWD plots have been updated from 320 to 300 degrees to optimize displaying maximum magnitudes of deformation consistent with the current activity at the summit of Kīlauea.
Kīlauea Summit:
Electronic Tilt at Kīlauea Summit, Station UWD - Past 2 Days
Electronic Tilt at Kīlauea Summit, Station UWD - Past 1 Week
Electronic Tilt at Kīlauea Summit, Station UWD - Past 3 Months
Electronic Tilt at Kīlauea Summit, Station UWD - Past 1 Year
Kīlauea East Rift Zone:
Electronic Tilt at Kīlauea East Rift Zone, Station POC - Past 2 Days
Electronic Tilt at Kīlauea East Rift Zone, Station POC - Past 1 Week
Electronic Tilt at Kīlauea East Rift Zone, Station POC - Past 3 Months
Electronic Tilt at Kīlauea East Rift Zone, Station POC - Past 1 Year
Global Positioning System
Global Positioning System (GPS), or more generally referred to as Global Navigation Satellite System (GNSS), records the precise location (longitude, latitude, altitude) and time data to determine exactly where a receiver is on Earth and when that location was recorded. Variations in daily solutions across a network of multiple stations can help scientists detect both horizontal and vertical movements of the ground surface, which on active volcanoes can be interpreted in relation to magma accumulation or movement beneath the surface.
- UWEV station is located on the northwest edge of Kīlauea's summit caldera.
- CRIM station is located directly opposite on the southern edge of Kilauea’s summit caldera.
- NPOC station is located just north of Pu‘u‘ō‘ō cone on the middle East Rift Zone of Kīlauea.
- MP3R station is located south of Pu‘u‘ō‘ō cone along the South Flank of Kilauea.
The plots below show the change in baseline distance between two Global Positioning System (GPS) stations. Positive trends in baseline length are associated with an increase in distance between the two station positions. For stations located on opposite sides of Kīlauea's summit caldera, a rapid increase in distance can be interpreted as inflation of the summit magma reservoir. Correspondingly, negative trends show contraction in baseline length and may relate to deflationary processes. Visit the HVO Deformation webpage to learn more.
Kīlauea Summit:
GPS at Kīlauea Summit, Stations UWEV and CRIM - Past 1 Month
GPS at Kīlauea Summit, Stations UWEV and CRIM - Past 1 Year
GPS at Kīlauea Summit, Stations UWEV and CRIM - Past 5 Years
Kīlauea East Rift Zone
Change in distance between two station near Pu‘u‘ō‘ō cone on the middle East Rift Zone of Kīlauea. A rapid increase in distance can be interpreted as inflation of the magma storage chambers in this area.
GPS at Kīlauea East Rift Zone, Stations NPOC and MP3R - Past 1 Month
GPS at Kīlauea East Rift Zone, Stations NPOC and MP3R - Past 1 Year
GPS at Kīlauea East Rift Zone, Stations NPOC and MP3R - Past 5 Years
Past Week Monitoring Data for Kīlauea
Past Month Monitoring Data for Kīlauea
Past Year Monitoring Data for Kīlauea
Past 5 Years Monitoring Data for Kīlauea
For more information on how electronic tiltmeters and GPS receivers help monitor the deformation of Kīlauea volcano, see the HVO Deformation page.
Electronic Tiltmeters
Electronic tiltmeters are used by the USGS Hawaiian Volcano Observatory to monitor small changes in local ground surface orientation relative to gravity.
- Click image at right for larger map. Data plots from additional stations are available from our interactive map, which allows you to view different types of data (using the right-side menu on the map).
- Station UWD is located near Uēkahuna, on the western rim of Kīlauea's summit caldera.
- Station POC is located on the north rim of Pu‘u‘ō‘ō cone on the middle East Rift Zone of Kīlauea.
In the plots below, the different colored lines show continuously operating electronic tiltmeter measurements made in a specific direction at a specific station, (see the legend in the upper left corner of each plot). The blue line shows radial tilt measurements which record changes perpendicular to surface-normal, and the green line shows tangential tilt measurements that record relative changes parallel to surface-normal. Positive changes in tilt near volcanoes often indicate inflation of the magma storage beneath the caldera or on the middle East Rift Zone of Kīlauea, but may also result from heavy rainfall or, occasionally, instrumental malfunctions. To optimize displaying maximum magnitudes of deformation at each station, tilt azimuths, (which range from 0-360 degrees), are determined based on current geophysical conditions and may need to be occasionally updated due to changes in activity. Tilt azimuth for UWD plots were last updated from 320 to 300 degrees on July 9, 2025. Visit the HVO Deformation webpage to learn more.
On July 9, 2025, tilt azimuths for SDH and UWD plots have been updated from 320 to 300 degrees to optimize displaying maximum magnitudes of deformation consistent with the current activity at the summit of Kīlauea.
Kīlauea Summit:
Electronic Tilt at Kīlauea Summit, Station UWD - Past 2 Days
Electronic Tilt at Kīlauea Summit, Station UWD - Past 1 Week
Electronic Tilt at Kīlauea Summit, Station UWD - Past 3 Months
Electronic Tilt at Kīlauea Summit, Station UWD - Past 1 Year
Kīlauea East Rift Zone:
Electronic Tilt at Kīlauea East Rift Zone, Station POC - Past 2 Days
Electronic Tilt at Kīlauea East Rift Zone, Station POC - Past 1 Week
Electronic Tilt at Kīlauea East Rift Zone, Station POC - Past 3 Months
Electronic Tilt at Kīlauea East Rift Zone, Station POC - Past 1 Year
Global Positioning System
Global Positioning System (GPS), or more generally referred to as Global Navigation Satellite System (GNSS), records the precise location (longitude, latitude, altitude) and time data to determine exactly where a receiver is on Earth and when that location was recorded. Variations in daily solutions across a network of multiple stations can help scientists detect both horizontal and vertical movements of the ground surface, which on active volcanoes can be interpreted in relation to magma accumulation or movement beneath the surface.
- UWEV station is located on the northwest edge of Kīlauea's summit caldera.
- CRIM station is located directly opposite on the southern edge of Kilauea’s summit caldera.
- NPOC station is located just north of Pu‘u‘ō‘ō cone on the middle East Rift Zone of Kīlauea.
- MP3R station is located south of Pu‘u‘ō‘ō cone along the South Flank of Kilauea.
The plots below show the change in baseline distance between two Global Positioning System (GPS) stations. Positive trends in baseline length are associated with an increase in distance between the two station positions. For stations located on opposite sides of Kīlauea's summit caldera, a rapid increase in distance can be interpreted as inflation of the summit magma reservoir. Correspondingly, negative trends show contraction in baseline length and may relate to deflationary processes. Visit the HVO Deformation webpage to learn more.
Kīlauea Summit:
GPS at Kīlauea Summit, Stations UWEV and CRIM - Past 1 Month
GPS at Kīlauea Summit, Stations UWEV and CRIM - Past 1 Year
GPS at Kīlauea Summit, Stations UWEV and CRIM - Past 5 Years
Kīlauea East Rift Zone
Change in distance between two station near Pu‘u‘ō‘ō cone on the middle East Rift Zone of Kīlauea. A rapid increase in distance can be interpreted as inflation of the magma storage chambers in this area.
GPS at Kīlauea East Rift Zone, Stations NPOC and MP3R - Past 1 Month
GPS at Kīlauea East Rift Zone, Stations NPOC and MP3R - Past 1 Year
GPS at Kīlauea East Rift Zone, Stations NPOC and MP3R - Past 5 Years
Past Week Monitoring Data for Kīlauea
Past Month Monitoring Data for Kīlauea
Past Year Monitoring Data for Kīlauea