Geohazard Supersites and Natural Laboratories

Report to DLRFalk Amelung, GEO task leader

September 2011

Hawaii Supersite

Halemaumau crater

Summit vent

Hawaii Supersite (1) : Kilauea crater rim instability

processed using 30 m DEM Richter & Poland, HVO Photos: HVO

TerraSAR-X interferogram

Halemaumau crater

Summit vent

processed using 3 m DEM Richter & Poland, HVO Photos: HVO

TerraSAR-X interferogram

Hawaii Supersite (1) : Kilauea crater rim instability

Summit vent

processed using 3 m DEM Richter & Poland, HVO

TerraSAR-X interferogram

Hawaii Supersite (1) : Kilauea crater rim instability

Growth with time

Richter & Poland, HVO

Hawaii Supersite (1) : Kilauea crater rim instability

• We are looking for a 0.5 fringe signal near the coast in this image• Atmospheric artifacts dominate the signal in each interferogram• Will use time series methods to extract the signature

Interferograms courtesy Piyush Agram

From Howard Zebker, Stanford University

Hawaii Supersite (2) : Slow Slip Event at Kilauea

Kilauea rift eruption March 2011

A propagating fissure (surface expression of a dike)

Baker and Amelung, U of Miami

Hawaii Supersite (3) : Kilauea’s magma system

February 2011 intrusion Post-intrusion inflation

LOS velocity from SBAS time-series

Envisat TSX

ALOS

GPS

Intrusion causes step in time series!

Disp

lace

men

t [cm

] GPS station inside caldera

Mt. Etna Supersite

Mt. Etna Supersite: TerraSAR-X

Descending Orbits

Time Interval:Sep 2008 – Dec 2009

27 acquisitions

76 Interferograms

Ground Resolution: ~ 30 meters

Look Angle: 42.9 deg

< -6 > 6cm/year

Mean deformation velocity

ENVISAT90x90 m

TerraSAR-X30x30 m

ENVISAT vs. TerraSAR-X: Spatial Coverage

TerraSAR-X vs. ENVISAT: Time Sampling

ENVISAT: 35 days

TerraSAR-X: 11 days

Tohoku-oki earthquake Supersite

E. Fielding, JPL

Tohoku-Oki earthquake event SupersitePixel tracking offset of M 6.6 aftershock of April 11

Colorscale 3 m 17 March, 19 April images

Septentrional fault:• GPS: ~10 mm/yr slip rate• Last earthquake about 1230 A.D. (8 m displacement accumulated) magnitude 7.5-8 overdue!

• seismic hazard very high in Dominican Republic!• pop. 10 million, 5 million tourists/yr• minimal seismic network (2 people)

•

USGS open file report

Hispaniola Supersite

Objective: estimate seismic hazard in Santiago, D. R. (2 million pop.)

~5 mm/yr LOS velocity

Hispaniola Supersite

TerraSAR-X interferograms11 days 22 days

Coherence sufficient slip rate measurement possible with 2-3 years of data!Need acquisitions every 11-22 days !

Expected signal

Fattahi, Wdowinski, Amelung, U of Miami