Geophysical observations of Kilauea Volcano, Hawaii, 2. Constraints on the magma supply during November 1975–September 1977

Dzurisin, Daniel; Anderson, L.A.; Eaton, Gordon P.; Koyanagi, Robert Y.; Lipman, Peter W.; Lockwood, John P.; Okamura, Reginald T.; Puniwai, G.S.; Sako, Maurice K.; Yamashita, Kenneth M.

doi:10.1016/0377-0273(80)90032-3

Cited by 107 publications

(34 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Deflation occurred within the summit caldera at Kilauea (USA), an active basaltic shield volcano, between 1975 and 1977 (Dzurisin et al 1980;Johnson 1987). Deflation began after a small summit eruption in late November 1975 and progressed for the following 2 years during four subsequent deflation periods.…”

Section: Kilaueamentioning

confidence: 98%

“…Figure 4 displays ∆g/∆h gradients derived from recorded gravity-deformation measurements between November-December 1975, December 1975-April 1977and April 1977-October 1977 (Table 1). Dzurisin et al (1980) calculated that 40-90×10 6 m 3 of void volume was created between November and December 1975 based on a Mogi-type source. The ∆g/∆h gradient of -171 µGal/m falls in region I (Fig.…”

Section: Kilaueamentioning

confidence: 99%

See 1 more Smart Citation

Deflation during caldera unrest: constraints on subsurface processes and hazard prediction from gravity–height data

Gottsmann

Rymer

2002

Bull Volcanol

View full text Add to dashboard Cite

We have evaluated published gravity-height (∆g/∆h) data on Campi Flegrei, Kilauea, Askja and Krafla, in order to discriminate between subsurface processes during caldera subsidence. With respect to end member gravity-height correlations, such as the free air gradient (FAG) and the Bouguer corrected free air (BCFAG), ∆g/∆h gradients must be interpreted in terms of subsurface mass redistribution, density changes or some combination of these. ∆g/∆h gradients during subsidence plot (1) along or below the BCFAG, (2) between the BCFAG and the FAG or (3) along or above the FAG. We have evaluated each of these three regions in terms of subsurface processes during volcano subsidence. We have interpreted ∆g/∆h gradients as possible indicators of precursors of volcanic activity and propose that gravityheight surveys may help to detect precursors of caldera collapse caused by magma drainage. In this context, the 1875 eruption of Askja in Iceland has been re-interpreted in terms of the beginning of the eruptive episode being induced by roof collapse of an evacuating magma chamber. Based on other examples of recent volcanic roof collapses, we evaluate the contribution of gravity-height surveys in assessing volcanic risks during caldera subsidence. Caldera-forming eruptions are environmentally and economically the most devastating volcanic events. Inflation is usually considered to be an important precursor to activity. Here, we show that deflation may be associated with the trigger mechanism for caldera-forming explosive eruptions.

show abstract

Section: Kilaueamentioning

confidence: 98%

Section: Kilaueamentioning

confidence: 99%

Deflation during caldera unrest: constraints on subsurface processes and hazard prediction from gravity–height data

Gottsmann

Rymer

2002

Bull Volcanol

View full text Add to dashboard Cite

show abstract

“…The October 1995-July 1996 variations (c) are associated with a withdrawal of magma from the source zone responsible for the previous change and the contemporary arrival of new magma in a source zone that is modeled as a prism-shaped body, whose projection onto the surface (Source 2) is also shown in (a) as a gray line (modified after BUDETTA et al, 1999). The central gravity increase (1994-1995)/ decrease (1995-1996) cycle reflects either voids around the central conduit being filled and drained, or changes in magmatic vesicularity (DZURISIN et al, 1980). The occurrence of the eccentric 1995-1996 gravity increase, close to the 1989 fracture system, suggests a passive mode of intrusion, perhaps with magma filling voids in the fracture system.…”

Section: Case Studiesmentioning

confidence: 99%

Review of Microgravity Observations at Mt. Etna: A Powerful Tool to Monitor and Study Active Volcanoes

Carbone

Greco

2007

Pure appl. geophys.

View full text Add to dashboard Cite

Microgravity observations at Mt. Etna have been routinely performed as both discrete (since 1986) and continuous (since 1998) measurements. In addition to describing the methodology for acquiring and reducing gravity data from Mt. Etna, this paper provides a collection of case studies aimed at demonstrating the potential of microgravity to investigate the plumbing system of an active volcano and detect forerunners to paroxysmal volcanic events.

show abstract

“…The mass change (∆M) within a spherical (point source) body, whose depth is much greater than its radius, causes a gravitational effect on the surface (∆g) that relate by (Dzurisin et al, 1980;Johnson, 1987;Rymer and Tryggvason, 1993):…”

Section: Gravity Datamentioning

confidence: 99%

Integration of micro-gravity and geodetic data to constrain shallow system mass changes at Krafla Volcano, N Iceland

et al. 2006

View full text Add to dashboard Cite

New and previously published micro-gravity data are combined with InSAR data, precise levelling and GPS measurements to produce a model for the processes operating at Krafla volcano, 20 years after its most recent eruption. The data have been divided into two periods: from 1990 to 1995 and from 1996 to 2003 and show that the rate of deflation at Krafla is decaying exponentially. The net micro-gravity change at the centre of the caldera is shown, using the measured Free Air Gradient, to be -85 µGal for the first and -100 µGal for the second period. After consideration of the effects of water extraction by the geothermal power station within the caldera, the net gravity decreases are -73 ± 17 µGal for the first and -65 ± 17 µGal for the second period. These decreases are interpreted in terms of magma drainage. Following a Mogi point source model we calculate the mass decrease to be ~2 x 10 10 kg/yr reflecting a drainage rate of ~0.23 m 3 /s, similar to the ~0.13 m 3 /s drainage rate previously found at Askja volcano, N-Iceland. Based on the evidence for deeper magma reservoirs and the similarity between the two volcanic systems, we suggest a pressure-link between Askja and Krafla at deeper levels (at the lower crust or the crust-mantle boundary). After the Krafla fires, co-rifting pressure decrease of a deep source at Krafla stimulated the subsequent inflow of magma, eventually affecting conditions along the plate boundary in N-Iceland, as far away as Askja. We anticipate that the pressure of the deeper reservoir at Krafla will reach a critical value and eventually magma will rise from there to the shallow magma chamber, possibly initiating a new rifting episode. We have demonstrated that by examining micro-gravity and geodetic data, our knowledge of active volcanic systems can be significantly improved.

show abstract

Geophysical observations of Kilauea Volcano, Hawaii, 2. Constraints on the magma supply during November 1975–September 1977

Cited by 107 publications

References 8 publications

Deflation during caldera unrest: constraints on subsurface processes and hazard prediction from gravity–height data

Deflation during caldera unrest: constraints on subsurface processes and hazard prediction from gravity–height data

Review of Microgravity Observations at Mt. Etna: A Powerful Tool to Monitor and Study Active Volcanoes

Integration of micro-gravity and geodetic data to constrain shallow system mass changes at Krafla Volcano, N Iceland

Contact Info

Product

Resources

About