Old Faithful Geyser, Yellowstone

Iconic & Predictable Geyser

Our schematic model proposes that Old Faithful’s formation is largely controlled by the surrounding geology (Wu et al., 2017).
The migration of bubble event (white cross) during Old Faithful’s eruption cycle (50 minutes before to 50 minutes after eruption) illustrates the plumbing structure and the evolution of Old Faithful (Wu et al., 2019).


Old Faithful is the iconic geyser in Yellowstone National Park, USA. Its fascinating eruption can eject water 30 m above the ground. To illuminate the plumbing architecture of Old Faithful, to understand why the geyser was isolated situating within the Upper Geyser Basin, and to peek how does the geyser recharge underground, we deployed two dense seismic arrays in the surrounding area and developed analyses based on seismic interferometry and polarization. Please check out our published works for the exciting findings of Old Faithful!

Keep in mind that Old Faithful still has some degrees of mystery. For example, Old Faithful is not as regular as it seemed and the mechanism of its bimodal eruption interval is unsolved. There are more to explore!

Related publications

Wu, S.-M., Ward, K. M., Farrell, J., Lin, F.-C., Karplus, M., & Smith, R. B. (2017). Anatomy of Old Faithful from subsurface seismic imaging of the Yellowstone Upper Geyser Basin, Geophysical Research Letters, 44(20). doi:10.1002/2017GL075255.

Wu, S.-M., Lin, F.-C., Allam, A., & Farrell, J. (2019). Imaging the deep subsurface plumbing of Old Faithful geyser from low-frequency hydrothermal tremor migration, Geophysical Research Letters, 46. https://doi.org/10.1029/2018GL081771.

Media and Outreach

AGU highlight GRL Commentary Science Smithsonian Atlas Obscura More

Caldera Chronicles (U.S. Geological Survey Yellowstone Volcano Observatory weekly column): “A new view of Old Faithful's underground plumbing system”.


Plumbing outline of Steamboat (star) and Cistern (square; Wu et al., submitted)



Steamboat Geyser, Yellowstone

Largest Geyser on Earth

Hydrological Connection to Cistern Spring

Steamboat Geyer is currently the largest (tallest) geyser on Earth, which can eject water over 120 m above the surface (3–4 times taller than Old Faithful!). Despite this, it is difficult to study Steamboat’s underlying physics because of its irregularity– the interval between eruptions ranging from 3 days to 50 years! What’s more? Steamboat is believed to be hydrologically connected to the nearby Spring, Cistern, approximately 100 m apart. Cistern drains in response to Steamboat’s major eruption since 1960s.

After years dormancy, Steamboat has entered into an active phase since March 2018 with more than 110 eruptions to date. This gives a chance to study this enigmatic yet fascinating wonder. We are super curious and excited to explore this questions:

What initiates Steamboat’s active phase? What controls Steamboat’s eruption interval? Why Steamboat is so tall? What are the underground plumbing structures of Steamboat and Cistern? How they are connected and interacted? What’s the role of Cistern? Does it modulate Steamboat’s activity? When and why the active phase ends? Can the eruption be predicted?

After a group’s effort, we have some of the answers but not all. Our findings about Steamboat and Cistern are on the way… stay tuned!!!

Related publications

Wu, S.-M., Lin, F.-C., Farrell, J., Keller, W., White, E., & Hungerford, J. (2021). Imaging the Subsurface Plumbing Complex of Steamboat Geyser and Cistern Spring with Hydrothermal Tremor Migration using Seismic Interferometry, Journal of Geophysical Research: Solid Earth, 126, e2020JB021128. https://doi.org/10.1029/2020JB021128.

Reed, M. H., Muñoz-Saez, C., Hajimirza, S., Wu, S. -M., Barth, A., Girona, T., Rasht-Behesht, M., White, E., Karplus, M. S., Hurwitz, S., & Manga, M. (2021). The 2018 reawakening and eruption dynamics of Steamboat Geyser, the world’s tallest active geyser, Proceedings of the National Academy of Sciences, 118. https://doi.org/10.1073/pnas.2020943118.


Media and Outreach

University press Salt Lake Tribune More

Caldera Chronicles (U.S. Geological Survey Yellowstone Volcano Observatory weekly column): “The complex plumbing systems of Steamboat Geyser and Cistern Spring”.




Kīlauea Volcano, Hawaii

2018 Volcano Eruption

Summit Collapse

Lava Effusion at Fissure 8


Fissure 8 eruption in 2018, photo credit to Brian Shiro

Kīlauea Volcano is currently the most active volcano on the island of Hawai'i (Big Island). In 2018, Kīlauea had undergone a new episode of eruption, with the majority of lava erupted from a series of new fissures in the lower East Rift Zone (LERZ), more than 30 km away from the summit through a dike intrusion. As magma drained from the summit system to feed the LERZ eruption, the summit caldera subsided in an episodic fashion through a series of 62 collapses. Following near-daily summit caldera collapse events, a surge of magma influx driven by reservoir pressurization migrated down to the LERZ and caused an increase in effusion rate observed at Fissure 8.

To better study the eruption dynamics and subsurface magma movement, we deployed temporary seismic nodal arrays across the volcanic system. Using our nodal data, we investigate the time-lapse changes in seismic velocity to understand how the crust responds to the summit collapse and the following magma pressurization. The results show clear, spatiotemporal velocity changes correlated to crustal damage, strengthening, and relaxation, which demonstrated that the magmatic activity at depth can be monitored using the nodal data, and can provide hazard assessments and new constraints on the time‐evolving mechanical structure of a volcano during a major eruption

Related publication

Wu, S.-M., Lin, F.-C., Farrell, J., Shiro, B., Karlstrom, L., Okubo, P., & Koper, K. (2020). Spatiotemporal Seismic Structure Variations Associated with the 2018 Kīlauea Eruption based on Temporary Dense Geophone Arrays, Geophysical Research Letters. 47, e2019GL086668. https://doi.org/10.1029/2019GL086668

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Cover Image for Geophysical Research Letters Volume47, Issue9