Seafloor deformation and forecasts of the April 2011 eruption at Axial Seamount

Journal name:
Nature Geoscience
Volume:
5,
Pages:
474–477
Year published:
DOI:
doi:10.1038/ngeo1464
Received
Accepted
Published online

Axial Seamount is an active submarine volcano located at the intersection between the Cobb hotspot and the Juan de Fuca spreading centre in the northeast Pacific Ocean1, 2. The volcano has been closely monitored since it erupted in 1998 (refs 3, 4). Since then, Axial Seamount seemed to exhibit a similar inflation–deflation cycle to basaltic volcanoes on land and, on that basis, was expected to erupt again sometime before 2014 or 2020 (refs 5, 6). In April 2011 Axial Seamount erupted. Here we report continuous measurements of ocean bottom pressure that document the deflation–inflation cycle of Axial Seamount between 1998 and 2011. We find that the volcano inflation rate, caused by the intrusion of magma, gradually increased in the months leading up to the 2011 eruption. Sudden uplift occurred 40–55min before the eruption onset, which we interpret as a precursor event. Based on our measurements of ground deformation through the entire eruption cycle at Axial Seamount, we suggest that another eruption could occur as early as 2018. We propose that the long-term eruptive cycle of Axial Seamount could be more predictable compared with its subaerial counterparts because the volcano receives a relatively steady supply of magma through the Cobb hotspot and because it is located on thin oceanic crust at a spreading plate boundary.

At a glance

Figures

  1. Bathymetric map of the summit caldera of Axial Seamount.
    Figure 1: Bathymetric map of the summit caldera of Axial Seamount.

    The locations of the two bottom pressure recorders (BPRs) that measured vertical movements of the sea floor during the 2011 eruption are shown, along with the lava flows that were erupted in April 2011 (blue outlines) and their eruptive vents (red lines), from ref. 7. The black dashed line shows the location of the model dyke (3.3km×2.0km×1.0m) that can reproduce the pre-eruption uplift observed at the BPRs. JdFR, Juan de Fuca Ridge; WA, Washington; OR, Oregon.

  2. BPR data from the 2011 eruption.
    Figure 2: BPR data from the 2011 eruption.

    a, Entire year-long, drift-corrected record from the center BPR, showing sudden deflation of −2.4m at the time of the 2011 eruption. b, Pre-eruption increase in inflation rate at centre BPR before the 2011 eruption. c, Detail near the eruption onset showing increased noise in the centre BPR, dyke-induced uplift and abrupt change to rapid deflation. d, Co-eruption deflation at an exponentially decreasing rate (blue) and temperature (red) recorded inside the centre-BPR pressure case. e, Co-eruption deflation (blue) and temperature (red) at the south BPR. f, Post-eruption re-inflation at an exponentially decreasing rate recorded by the centre BPR. a, b and f are low-pass filtered to remove tides and show long-term trends; cd and e have a tide model26 subtracted to retain high-frequency information.

  3. Two forecast scenarios for the next eruption at Axial Seamount, based on the cycle of inflation and deflation.
    Figure 3: Two forecast scenarios for the next eruption at Axial Seamount, based on the cycle of inflation and deflation.

    In both, the intereruption MPR data (purple dots, error bars as in ref. 6) are coregistered with the 2011 centre BPR data (blue), but their exact relationship (in relative depth) to the 1998 BPR data (red) is unknown. a, Time-predictable model in which eruptions (deflations) are triggered at a critical level of inflation and the next eruption at Axial would be expected in 2018. b, Volume-predictable model in which the volume of the next eruption is predictable based on the time since the last one, but the date it will occur is unknown.

References

  1. Johnson, H. P. & Embley, R. W. Axial Seamount: An active ridge axis volcano on the central Juan de Fuca Ridge. J. Geophys. Res. 95, 1268912696 (1990).
  2. Chadwick, J. et al. Magmatic effects of the Cobb hotspot on the Juan de Fuca Ridge. J. Geophys. Res. 110, B03101 (2005).
  3. Embley, R. W., Chadwick, W. W.Jr, Clague, D. & Stakes, D. The 1998 eruption of Axial volcano: Multibeam anomalies and seafloor observations. Geophys. Res. Lett. 26, 34253428 (1999).
  4. Chadwick, W. W.Jr et al. Spotlight 1: Axial Seamount. Oceanography 23, 3839 (2010).
  5. Chadwick, W. W.Jr, Nooner, S., Zumberge, M., Embley, R. W. & Fox, C. G. Vertical deformation monitoring at Axial Seamount since its 1998 eruption using deep-sea pressure sensors. J. Volcanol. Geotherm. Res. 150, 313327 (2006).
  6. Nooner, S. L. & Chadwick, W. W.Jr Volcanic inflation measured in the caldera of Axial Seamount: Implications for magma supply and future eruptions. Geochem. Geophys. Geosyst. 10, Q02002 (2009).
  7. Caress, D. W. et al. High-resolution AUV surveys reveal new lava from the April 2011 eruption at Axial Seamount. Nature Geosci. (in the press).
  8. Dziak, R. P. et al. Seismic precursors and magma ascent before the April 2011 eruption at Axial Seamount. Nature Geosci. (in the press).
  9. Dvorak, J. J. & Dzurisin, D. Volcano geodesy: The search for magma reservoirs and the formation of eruptive vents. Rev. Geophys. 35, 343384 (1997).
  10. Sturkell, E. et al. Volcano geodesy and magma dynamics in Iceland. J. Volcanol. Geotherm. Res. 150, 1434 (2006).
  11. Fox, C. G. In situ ground deformation measurements from the summit of Axial volcano during the 1998 volcanic episode. Geophys. Res. Lett. 26, 34373440 (1999).
  12. Polster, A., Fabian, M. & Villinger, H. Effective resolution and drift of paroscientific pressure sensors derived from long-term seafloor measurements. Geochem. Geophys. Geosyst. 10, Q08008 (2009).
  13. West, M. E., Menke, W., Tolstoy, M., Webb, S. & Sohn, R. Magma storage beneath Axial volcano on the Juan de Fuca mid-ocean ridge. Nature 413, 833836 (2001).
  14. Carbotte, S. M. et al. Variable crustal structure along the Juan de Fuca Ridge: Influence of on-axis hot spots and absolute plate motions. Geochem. Geophys. Geosyst. 9, Q08001 (2008).
  15. Okada, Y. Internal deformation due to shear and tensile faults in a half-space. Bull. Seismol. Soc. Am. 82, 10181040 (1992).
  16. Chadwick, W. W.Jr et al. The May 2005 eruption of Fernandina volcano, Galápagos: The first circumferential dike intrusion observed by GPS and InSAR. Bull. Volcanol. 73, 679697 (2011).
  17. Dziak, R. P. & Fox, C. G. The January 1998 earthquake swarm at Axial volcano, Juan de Fuca Ridge: Hydroacoustic evidence of seafloor volcanic activity. Geophys. Res. Lett. 26, 34293432 (1999).
  18. Dvorak, J. J. & Okamura, A. T. A hydraulic model to explain variations in summit tilt rate at Kilauea and Mauna Loa volcanoes. US Geol. Surv. Prof. Pap. 1350, 12811296 (1987).
  19. Mogi, K. Relations between the eruptions of various volcanoes and the deformation of the ground surfaces around them. Bull. Earthq. Res. I. Tokyo 36, 99134 (1958).
  20. Chadwick, W. W.Jr, Embley, R. W., Milburn, H. B., Meinig, C. & Stapp, M. Evidence for deformation associated with the 1998 eruption of Axial Volcano, Juan de Fuca Ridge, from acoustic extensometer measurements. Geophys. Res. Lett. 26, 34413444 (1999).
  21. Fox, C. G., Chadwick, W. W.Jr & Embley, R. W. Direct observation of a submarine volcanic eruption from a sea-floor instrument caught in a lava flow. Nature 412, 727729 (2001).
  22. Jaupart, C. & Vergniolle, S. The generation and collapse of a foam layer at the roof of a basaltic magma chamber. J. Fluid Mech. 203, 347380 (1989).
  23. Tait, S., Jaupart, C. & Vergniolle, S. Pressure, gas content, and eruption periodicity of a shallow crystallising magma chamber. Earth Planet. Sci. Lett. 92, 107123 (1989).
  24. Helo, C., Longpre, M. A., Shimizu, N., Clague, D. A. & Stix, J. Explosive eruptions at mid-ocean ridges driven by CO2-rich magmas. Nature Geosci. 4, 260263 (2011).
  25. http://www.ooi.washington.edu/.
  26. Agnew, D. NLOADF: A program for computing ocean-tide loading. J. Geophys. Res. 102, 51095110 (1997).

Download references

Author information

Affiliations

  1. Oregon State University/Cooperative Institute for Marine Resources Studies, 2115 SE OSU Drive, Newport, Oregon 97365, USA

    • William W. Chadwick Jr
  2. Columbia University, Department of Earth and Environmental Sciences, New York 10027, USA

    • Scott L. Nooner
  3. University of Washington/Joint Institute for the Study of the Atmosphere and Ocean, Seattle, Washington 98195, USA

    • David A. Butterfield
  4. University of Washington, School of Oceanography, Seattle, Washington 98195, USA

    • Marvin D. Lilley

Contributions

W.W.C. and S.L.N. contributed equally to this work. W.W.C. wrote the manuscript. D.A.B. and M.D.L. were co-principal investigators on the expedition that discovered the 2011 eruption at Axial Seamount.

Competing financial interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to:

Author details

Additional data