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J. B. Stokes

Publications and source records attributed to J. B. Stokes.

6 recordsLinked to original sources
USGS2001

Implications for eruptive processes as indicated by sulfur dioxide emissions from Kilauea Volcano, Hawai'i, 1979-1997

Kı̄lauea Volcano, Hawai‘i, currently hosts the longest running SO 2 emission-rate data set on the planet, starting with initial surveys done in 1975 by Stoiber and his colleagues. The 17.5-year record of summit emissions, starting in 1979, shows the effects of summit and east rift eruptive processes, which define seven distinctly different periods of SO 2 release. Summit emissions jumped nearly 40% with the onset (3 January 1983) of the Pu`u `Ō`ō-Kūpaianaha eruption on the east rift zone (ERZ). Summit SO 2 emissions from Kı̄lauea showed a strong positive correlation with short-period, shallow, caldera events, rather than with long-period seismicity as in more silicious systems. This correlation suggests a maturation process in the summit magma-transport system from 1986 through 1993. During a steady-state throughput-equilibrium interval of the summit magma reservoir, integration of summit-caldera and ERZ SO 2 emissions reveals an undegassed volume rate of effusion of 2.1×10 5 m 3 /d. This value corroborates the volume-rate determined by geophysical methods, demonstrating that, for Kı̄lauea, SO 2 emission rates can be used to monitor effusion rate, supporting and supplementing other, more established geophysical methods. For the 17.5 years of continuous emission rate records at Kı̄lauea, the volcano has released 9.7×10 6 t (metric tonnes) of SO 2 , 1.7×10 6 t from the summit and 8.0×10 6 t from the east rift zone. On an annual basis, the average SO 2 release from Kı̄lauea is 4.6×10 5 t/y, compared to the global annual volcanic emission rate of 1.2×10 7 t/y.

Journal of Volcanology and Geothermal Research↗
USGS1998

Sulfur dioxide emission rates of Kilauea Volcano, Hawaii, 1979-1997

Sulfur dioxide (SO 2 ) emission rates from Kilauea Volcano were first measured by Stoiber and Malone (1975) and have been measured on a regular basis since 1979 (Casadevall and others, 1987; Greenland and others, 1985; Elias and others, 1993; Elias and Sutton, 1996). The purpose of this report is to present a compilation of Kilauea SO 2 emission rate data from 1979 through 1997 with ancillary meteorological data (wind speed and wind direction). We have included measurements previously reported by Casadevall and others (1987) for completeness and to improve the usefulness of this current database compilation. Kilauea releases SO 2 gas predominantly from its summit caldera and rift zones (fig. 1). From 1979 through 1982, vehicle-based COSPEC measurements made within the summit caldera were adequate to quantify most of the SO 2 emitted from the volcano. Beginning in 1983. the focus of SO 2 release shifted from the summit to the east rift zone (ERZ) eruption site at Pu'u 'O'o and, later, Kupaianaha. Since 1984, the Kilauea gas measurement effort has been augmented with intermittent airborne and tripod-based surveys made near the ERZ eruption site. In addition, beginning in 1992 vehicle-based measurements have been made along a section of Chain of Craters Road approximately 9 km downwind of the eruption site. These several types of COSPEC measurements continue to the present.

Hawaii↗
USGS1989

SO2 from episode 48A eruption, Hawaii: Sulfur dioxide emissions from the episode 48A East Rift Zone eruption of Kilauea volcano, Hawaii

An SO2 flux of 1170??400 (1??) tonnes per day was measured with a correlation spectrometer (COSPEC) in October and November 1986 from the continuous, nonfountaining, basaltic East Rift Zone eruption (episode 48A) of Kilauea volcano. This flux is 5-27 times less than those of highfountaining episodes, 3-5 times greater than those of contemporaneous summit emissions or interphase Pu'u O'o emissions, and 1.3-2 times the emissions from Pu'u O'o alone during 48A. Calculations based on the SO2 emission rate resulted in a magma supply rate of 0.44 million m3 per day and a 0.042 wt% sulfur loss from the magma upon eruption. Both of these calculated parameters agree with determinations made previously by other methods. ?? 1989 Springer-Verlag.

Bulletin of Volcanology↗
USGS1988

Detailed record of SO2 emissions from Pu'u `O`o between episodes 33 and 34 of the 1983-86 ERZ eruption, Kilauea, Hawaii

A tripod-mounted correlation spectrometer was used to measure SO2 emissions from Pu`u `O`o vent, mid-ERZ, Kilauea, Hawaii between Episodes 33 and 34 (June 13 to July 6, 1985). In 24 repose days, 906 measurements were collected, averaging 38 determinations/day. Measurements reflect 13% of the total 576 hours of the repose and 42% of the bright daylight hours. The average SO2 emission for the 24-day repose interval is 167??83 t/d, a total of 4000 tonnes emitted for the entire repose. The large standard deviation reflects the "puffing" character of the plume. The overall rate of SO2 degassing gently decreased with a zero-intercept of 44-58 days and was interrupted by two positive peaks. The data are consistent with the gas emanating from a cylindrical conduit of 50 meter diameter and a length of 1700 meters which degasses about 50% of its SO2 during 24 days. This is in support of the Pu'u `O`o model of Greenland et al. (1987). 36 hours before the onset of Episode 34 (July 5-6, 1985), elevated SO2 emissions were detected while the magma column was extremely active ultimately spilling over during dome fountaining. A "mid-repose" anomaly of SO2 emission (June 21-22, 1985) occurs two days before a sudden increase in the rate of summit inflation (on June 24, 1985), suggesting magma was simultaneously being injected in both the ERZ and summit reservoir until July 24 when it was channelled only to the summit reservoir. This implies degassing magma is sensitive to perturbations within the rift zone conduit system and may at times reflect these disturbances. Periods of 7-45 min are detected in the daily SO2 emissions, which possibly reflect timing of convective overturn in the cylindrical magma body. If the 33-34 repose interval is considered representative of other repose periods, the ERZ reposes of Jan 1983-Jan 1986 ERZ activity, contributed 1.6 ?? 105 tonnes of SO2 to the atmosphere. Including summit fuming from non-eruptive fumaroles (2.7 ?? 105 tonnes SO2); 28% of the total SO2 budget from Kilauea between Jan 1983 to Jan 1986 was contributed by quiescent degassing, and the remainder was released during explosive fountaining episodes. ?? 1988 Springer-Verlag.

Bulletin of Volcanology↗
USGS1985

An estimate of gas emissions and magmatic gas content from Kilauea volcano

Emission rates of CO 2 have been measured at Kilauea volcano, Hawaii, in the east-rift eruptive plume and CO 2 and SO 2 have been measured in the plume from the noneruptive fumaroles in the summit caldera. These data yield an estimate of the loading of Kilauean eruptive gases to the atmosphere and suggest that such estimates may be inferred directly from measured lava volumes. These data, combined with other chemical and geologic data, suggest that magma arrives at the shallow summit reservoir containing (wt.%) 0.32% H 2 O, 0.32% CO 2 and 0.09% S. Magma is rapidly degassed of most of its CO 2 in the shallow reservoir before transport to the eruption site. Because this summit degassing yields a magma saturated and in equilibrium with volatile species and because transport of the magma to the eruption site occurs in a zone no shallower than the summit reservoir, we suggest that eruptive gases from Kilauea characteristically should be one of two types: a ‘primary’ gas from fresh magma derived directly from the mantle and a carbon-depleted gas from magma stored in the summit reservoir.

Geochimica et Cosmochimica Acta↗