Vertical deformation monitoring at Axial Seamount since its 1998 eruption using deep-sea pressure sensors

Publication Type  Journal Article
Year of Publication  2006
Authors  Chadwick, W. W.; Nooner, S. L.; Zumberge, M. A.; Embley, R. W.; Fox, C. G.
Journal Title  Journal of Volcanology and Geothermal Research
Volume  150
Issue  1-3
Pages  313-327
Journal Date  Feb 1
ISBN Number  0377-0273
Accession Number  ISI:000235593400021
Key Words  volcano inflation; ground deformation monitoring; seafloor geodesy; bottom pressure recorder; kilauea volcano; fuca ridge; ground deformation; midocean ridge; radar interferometry; continental-margin; magma accumulation; surface uplift; 1960 collapse; oce

Pressure measurements made on the seafloor at depths between 1500 and 1700 m at Axial Seamount, an active submarine volcano on the Juan de Fuca Ridge in the northeast Pacific Ocean, show evidence that it has been inflating since its 1998 eruption. Data from continuously recording bottom pressure sensors at the center of Axial's caldera suggest that the rate of inflation was highest in the months right after the eruption (20 cm/month) and has since declined to a steady rate of similar to 15 cm/year. Independent campaign-style pressure measurements made each year since 2000 at an array of seafloor benchmarks with a mobile pressure recorder mounted on a remotely operated vehicle also indicate uplift is occurring in the caldera at a rate up to 22 +/- 1.3 cm/year relative to a point outside the caldera. The repeatability of the campaign-style pressure measurements progressively improved each year from +/- 15 cm in 2000 to +/- 0.9 cm in 2004, as errors were eliminated and the technique was refined. Assuming that the uplift has been continuous since the 1998 eruption, these observations suggest that the center of the caldera has re-inflated about 1.5 +/- 0.1 m, thus recovering almost 50% of the 3.2 m of subsidence that was measured during the 1998 eruption. This rate of inflation can be used to calculate a magma supply rate of 14 x 10(6) m(3)/year. If this rate of inflation continues, it also suggests a recurrence interval of similar to 16 years between eruptions at Axial, assuming that it will be ready to erupt again when it has re-inflated to 1998 levels. (c) 2005 Elsevier B.V. All rights reserved.


016ARTimes Cited:5Cited References Count:57

URL  <Go to ISI>://000235593400021
DOI  DOI 10.1016/j.jvolgeores.2005.07.006