Mapping the Bubble Trap Feeding Eruptions of Strokkur Geyser, Iceland

Abstract

<p>Geysers are characterized by regular eruptions of hot water fountains. Their internal system consists of a heat source at depth, an often complex crack system and a conduit linking it to the surface. The conduit and crack system is filled with water, steam and gases similar to a volcano. Bubble traps are sometimes and rarely mapped and alternative heat-driven models for geyser eruptions exist.</p><p>Using a multidisciplinary, dense and close network of video cameras, seismometers, water pressure sensors and a tiltmeter we studied pool geyser Strokkur in June 2018. These multidisciplinary observations and particle-motion based tremor locations enabled us to derive a schematic cross section describing the driving mechanisms and the fluid dynamic processes within the bubble trap, crack system and conduit. We imaged a bubble trap at 23.7+-4.4 m depth, 13 to 23 m west of the conduit. We divide the eruptive cycle into eruption, refilling of the conduit, gas accumulation in the bubble trap and a trail of bubbles from the bubble trap into the conduit where they collapse at depth and have gained novel insights in understanding the gas accumulation, migration and collapse in such hot geyser systems in different phases of the eruptive cycle.</p><p>The dataset of this experiment can be accessed here:</p><p><strong>- Eibl, E. P. S.</strong>, Müller, D., Allahbakhshi, M., Walter, T. R., Jousset, P., Hersir, G. P., Dahm, T., (2020) ' Multidisciplinary dataset at the Strokkur Geyser, Iceland, allows to study internal processes and to image a bubble trap.' GFZ Data Services. DOI: 10.5880/GFZ.2.1.2020.007</p><p>- <strong>Eibl, E. P. S.</strong>; Walter, T.; Jousset, P.; Dahm, T.; Allahbakhshi, M.; Müller, D.; Hersir, G.P. (2020): 1 year seismological experiment at Strokkur in 2017/18. GFZ Data Services. Other/Seismic Network. DOI:10.14470/2Y7562610816</p>

Eruption Forecasting of Strokkur Geyser, Iceland, Using Permutation Entropy

“…We used seismic data recorded at 5–14 m distance south and east of the pool of Strokkur geyser, Iceland (Eibl, Walter, et al., 2020). The sensors are Nanometrics Trillium Compact Posthole 20 s seismometers at locations S2, S3, S5 and Nanometrics Trillium Compact 120 s at locations S1, S4 (see Figure 1b) in the 7L seismic network (Eibl, Walter, et al., 2020). The seismometers were installed on 10 June 2018 for 4.5–5.25 hr and recorded at a sampling rate of 400 Hz.…”

Multi-parametric observations of intermittent hydrothermal discharge in West Crater of Iwo-Yama volcano, Kirishima Volcanic Complex, Japan

“…The elevation of West Crater is 1233 m, and the boiling point of pure water at this elevation is approximately 96°C. Previous studies of geysers have reported that water temperature rises at the time of geyser eruption (e.g., Nishimura et al, 2006;Eibl et al, 2021).…”

“…The seismic signals recorded at Old Faithful geyser in Yellowstone National Park, which has a vent opening of approximately 2 m × 1 m, are generated by bubble activity (growing, collapsing, or moving of bubbles) in boiling uid in the geyser conduit (Kieffer, 1984;Kedar et al, 1996;Kedar and Kanamori, 1998). Eibl et al (2021) reported that seismic tremors at Old Faithful are clustered in two dominant source locations: a deeper location (approximately 23.7 m depth) representing a sealed bubble reservoir, and a shallower location (approximately 5 m depth) representing the conduit.…”

“…In addition to visual imaging in geyser conduits (e.g., Belousov et al, 2013), geophysical observations at the surface have been conducted around geysers. For example, the measurement of temperature (e.g., Nishimura et al, 2006;Eibl et al, 2021) and pressure (e.g., Kedar and Kanamori, 1996;Kedar et al, 1998) in the conduit, seismic tremor (e.g., Kieffer, 1984;Kedar et al, 1996;Eibl et al, 2021), tilt motion (e.g., Nishimura et al, 2006;Vandemeulebrouck et al, 2014;Eibl et al, 2021), and acoustic waves (e.g., Nishimura et al, 2006;Johnson et al, 2013;Vandemeulebrouck et al, 2014). Cyclic change in electric self-potential (SP) has also been observed around geysers (Nishi et al, 2000;Legaz et al, 2009).…”