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Falk Amelung RSMAS - University of Miami Sang-Ho Yun Stanford University Thomas Walter now at GFZ Potsdam Asta Miklius Hawaii Volcano Observatory

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Falk Amelung RSMAS - University of Miami

Sang-Ho YunStanford University

Thomas Walternow at GFZ Potsdam

Asta MikliusHawaii Volcano Observatory

Pinatubo 1991

Luzon M7.8earthquake

100 km

Mount Pinatuboerupted 9 monthsafter earthquake

Bautista et al., 98

Did the earthquake trigger the eruption, and how ?

Karymksy 1996

50 km

M7.2 1996earthquake

Karymskyerupted 2 daysafter earthquake

Karymksy 1996

Static stress changes may explain the eruption !

Static stress changes due to earthquake

Galapagos Islands

Fernandina

Isabela Island

Fernandina1992-1998 ERS interferog

1995 radial dike

2005 circum-ferential dike

Jonsson et al.,

FernandinaEruptions in1995,13 May 2005

Galapagos Islands

Fernandina

Isabela Island

Fernandina1992-1998 ERS interferog

1995 radial dike

2005 circum-ferential dike

Jonsson et al.,

Static stress changesFernandina1992-1998 ERS interferog

1995 radial dike

2005 circum-ferential dike

Modelling of changes in the stress field along caldera-bounding “rift zone”

Static stress changesFernandina1992-1998 ERS interferog

1995 radial dike

2005 circum-ferential dike

clampingunclamping

Normal stress

3D view

Static stress changesFernandina1992-1998 ERS interferog

1995 radial dike

2005 circum-ferential dike

clampingunclamping

Normal stress

3D view

Conclusion:2005 dike intruded in area un-clamped by the 1995 dike !

unclamping

Fernandina1992-1998 ERS interferog

1995 radial dike

2005 circum-ferential dike

clampingunclamping

unclamping

Fernandina and Isabela Islands - Ground DeformationSierra Negra volcano

0

trapdoor faulting in 1998

Sill at 2 km depth

Sierra Negra volcano

ERS interferograms

Fernandina and Isabela Islands - Ground Deformation0

trapdoor faulting in spring 200

Sierra Negra volcano

Envisat interferograms

Sierra Negra volcano0

north-south cross-section

eruption 22 Oct 2005 trapdoor faulting in spring 20

Envisat interferograms

eruptions 1979, 2005

?, 1998, 2005

Conclusion:2005 eruption site consistent with propagating sill model

sill propagation model

Simulation: Sang-ho Yun

The Hawaiian Volcanoes

Mauna Loa: eruptions in 1950, 1984Kilauea: continuous eruption since 1983

Photos: HVO

Mauna Loa volcano, Hawaii

Inflation since May 2002~ 7 cm/yr extension across caldera

ALEP

ELEP

Mauna Loa volcano, Hawaii2002-2003 Radarsat A3 interferogram

Stacked Interferograms

Ascending,Beam 3

Mauna Loa volcano, Hawaii

stack of 4 Interferogramsascending S3

Stacked Interferograms una Loa volcano, stacks of RSAT interferogra

Stacked Interferograms una Loa volcano, stacks of RSAT interferogra

Stacked Interferograms una Loa volcano, stacks of RSAT interferogra

Mauna Loa volcano: Kinematic Model

2-D velocity fieldfrom ~80 acquisitions

Mauna Loa volcano: Kinematic Model

Mauna Loa volcano: Kinematic Model

Mauna Loa volcano: Kinematic Model

Opening along Rift Zone

- maximum dike inflation south of caldera beneath summit resedeep rift intrusion, 0.25 m/yr openingmagma chamber, 4.5 km depth, 1-1.3 km radius

Kinematic model Dynamic model

variable magma excess pressure, point source,

halfspace

uniform magma excess pressure, finite source, topography (Williams & Wadge

method)

Mauna Loa magma plumbing system

Opening along Rift Zone

- maximum dike inflation south of caldera beneath summit rese

deep rift intrusion magma chamber 1-1.3 km radius

Dynamic model

uniform magma excess pressure, finite source, topography (Williams & Wadge

method)

Mauna Loa magma plumbing system

Opening along Rift Zone

- maximum dike inflation south of caldera beneath summit reseInflation of magma plumbing System encourages decollement faulting !

Status stress changes

Conclusions

Fernandina: stress-transfer model predict location of

2005 circumferential dikeSierra Negra: sill propagation model pre

2005 eruptive dike

Mauna Loa: decollement slip consistent witchanges due to the inflation of

model magmatic sy

Conclusions

Fernandina: stress-transfer model predict location of

2005 circumferential dikeSierra Negra: sill propagation model pre

2005 eruptive dike

Mauna Loa: decollement slip consistent witchanges due to the inflation of

model magmatic sy

job ad: grad. student, opportuniti