Keanakākoʻi Tephra produced by 300years of explosive eruptions following collapse of Kīlauea's caldera in about 1500CE

Swanson, Donald A.; Rose, T.; Fiske, Richard S.; McGeehin, John P.

doi:10.1016/j.jvolgeores.2011.11.009

Cited by 72 publications

(61 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This deposit can be mapped to the coast (20 km distant) and its southeastward dispersal direction implies columns that extended into the jet stream, most likely to >12 km. Despite the high intensity, this eruption had a relatively small volume of c. 0.02 km 3 (Swanson et al, 2012).…”

Section: Melt Embayments and Choice Of Samplesmentioning

confidence: 92%

“…A thick reticulite-pumice layer formed from an eruption in c. 1500 CE (Swanson et al, 2012;May et al, 2015), which is present on all sides of Kīlauea Caldera and is more widely dispersed than deposits from any historical high-fountaining eruption. Ascent and mass discharge rates for this deposit are probably larger than for any historical eruption, with fountain heights exceeded 600 m.…”

Section: Melt Embayments and Choice Of Samplesmentioning

confidence: 99%

“…Furthermore, at some volcanoes, such as Kīlauea, there is evidence for past explosive eruptions that have no historically observed equivalent in intensity (e.g. Swanson et al, 2012Swanson et al, , 2014May et al, 2015) and the conditions that accompany such intensely explosive eruptions remain largely unresolved. Since a number of important processes are directly dependent on the decompression rate, such as bubble nucleation, bubble growth, and fragmentation itself (Parfitt and Wilson, 1995;Mangan and Cashman, 1996;Mangan et al, 2014;Gonnermann, 2015), robust constraints on this parameter will enable a fuller understanding of the processes that determine the intensity of explosive eruptions driven by magmatic volatiles.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Magma decompression rates during explosive eruptions of Kīlauea volcano, Hawaii, recorded by melt embayments

et al. 2016

Self Cite

View full text Add to dashboard Cite

The decompression rate of magma as it ascends during volcanic eruptions is an important but poorly constrained parameter that controls many of the processes that influence eruptive behaviour. In this study we quantify decompression rates for basaltic magmas using volatile diffusion in olivine-hosted melt tubes (embayments) for three contrasting eruptions of Kīlauea volcano, Hawai'i. Incomplete exsolution of H 2 O, CO 2 and S from the embayment melts during eruptive ascent creates diffusion profiles that can be measured using microanalytical techniques, and then modelled to infer the average decompression rate. We obtain average rates of ~0.05-0.45 MPa s -1 for eruptions ranging from Hawaiian style fountains to basaltic subplinian, with the more intense eruptions having higher rates. The ascent timescales for these magmas vary from around ~5 to ~36 minutes from depths of ~2 to ~4 km respectively. Decompression-exsolution models based on the embayment data also allow for an estimate of the mass fraction of pre-existing exsolved volatiles within the magma body. In the eruptions studied this varies from 0.1-3.2 wt%, but does not appear to be the key control on eruptive intensity. Our results do not support a direct link between the concentration of pre-eruptive volatiles and eruptive intensity; rather they suggest that for these eruptions decompression rates are proportional to independent estimates of mass discharge rate. Although the intensity of eruptions is defined by the discharge rate, based on the currently available dataset of embayment analyses it does not appear to scale linearly with average decompression rate. This study demonstrates the utility of the embayment method for providing quantitative constraints on magma ascent during explosive basaltic eruptions.

show abstract

Section: Melt Embayments and Choice Of Samplesmentioning

confidence: 92%

Section: Melt Embayments and Choice Of Samplesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Magma decompression rates during explosive eruptions of Kīlauea volcano, Hawaii, recorded by melt embayments

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…An older caldera has been inferred to have existed between 1500 and 2100 years ago [Powers, 1948]. The current caldera formed about 1470-1510 Common Era based on 14 C dating of postcaldera tephra deposits and precaldera lava flows [Swanson et al, 2012] and consistent with Hawaiian oral traditions [Swanson, 2008].…”

Section: Geologic Setting and Previous Workmentioning

confidence: 99%

“…[27] Swanson et al [2012] place the date of Kīlauea's most recent caldera formation event at~500 years ago and infer that the collapse created a depression~400 m deeper than the caldera is today. The 3.0 km 3 dense body inferred in this study begins at 350 to 400 m below the surface and is consistent with the level of the postcollapse caldera floor.…”

Section: à3mentioning

confidence: 99%

The shallow structure of Kīlauea caldera from high‐resolution Bouguer gravity and total magnetic anomaly mapping: Insights into progressive magma reservoir growth

Zurek

Williams‐Jones

2013

JGR Solid Earth

View full text Add to dashboard Cite

We conducted total magnetic field and Bouguer gravity measurements to investigate the shallow structure beneath the summit caldera of Kīlauea Volcano, Hawai'i. Two significant and distinctive magnetic anomalies were identified within the caldera. One is interpreted to be associated with a long‐lived prehistoric eruptive center, the Observatory vent, located ~1 km east of the Hawaiian Volcano Observatory. The second magnetic anomaly corresponds to a set of eruptive fissures that strike northeast from Halema'uma'u Crater, suggesting this is an important transport pathway for magma. The Bouguer gravity data were inverted to produce 3‐D models of density contrasts in the upper 2 km beneath Kīlauea. The models detect 3.0 km3 of material, denser than 2800 kg m−3, beneath the caldera that may represent an intrusive complex centered northeast of Halema'uma'u. Recent temporal gravity studies indicate continual addition of mass beneath the caldera during 1975–2008 centered west of Halema'uma'u and suggest this is due to filling of void space. The growth of a large intrusive complex, apparent cyclical caldera formation, and continual mass addition without inflation, however, can also be explained by extensional rifting caused by the continual southward movement of Kīlauea's unstable south flank.

show abstract

Mafic Plinian eruptions: Is fast ascent required?

Szramek

2016

JGR Solid Earth

View full text Add to dashboard Cite

It has been hypothesized that for a Plinian eruption of mafic magma to occur, that magma must ascend rapidly from the chamber to cause it to fragment into a jet containing juvenile and nonjuvenile tephra. To determine how fast mafic Plinian magmas need to travel to the level of fragmentation, a number of decompression experiments were carried out on two hydrous mafic magmas, and the results are compared to the products of two well‐documented mafic Plinian eruptions: the basaltic andesite Fontana eruption of Masaya (Nicaragua) and the hawaiite 122 B.C. eruption of Etna (Italy). Comparison of natural and experimental textures shows that the Fontana eruption can be replicated in the lab at decompression rates between 0.1 MPa s−1 and 0.2 MPa s−1. This decompression rate is faster than any previously determined experimentally rate for more silicic eruptions. The hawaiite was unable to be reproduced in the lab. The natural groundmass is highly crystalline, which would have raised the viscosity of the initial melt by 1–2 orders of magnitude, which may not be enough to cause fragmentation.

show abstract

Keanakākoʻi Tephra produced by 300years of explosive eruptions following collapse of Kīlauea's caldera in about 1500CE

Cited by 72 publications

References 19 publications

Magma decompression rates during explosive eruptions of Kīlauea volcano, Hawaii, recorded by melt embayments

Magma decompression rates during explosive eruptions of Kīlauea volcano, Hawaii, recorded by melt embayments

The shallow structure of Kīlauea caldera from high‐resolution Bouguer gravity and total magnetic anomaly mapping: Insights into progressive magma reservoir growth

Mafic Plinian eruptions: Is fast ascent required?

Contact Info

Product

Resources

About