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KIT – University of the State of Baden-Wuerttemberg and National Research Center of the Helmholtz Association
Geodetic Institute, Department of Civil Engineering, Geo and Environmental Sciences
www.kit.edu
J. Kubanek, M. Westerhaus, B. Heck Karlsruhe Institute of Technology, Germany
Measuring topographic changes at active volcanoes by double differential TanDEM-X InSAR
© DLR
Geodetic Institute 2
Motivation
01.04.2015
h
SATt=1 SATt=2
𝑟𝑟1
The repeat pass intervals of current radar satellite missions are long
Changing backscattering conditions lead to low coherence problematic in summit areas, near lava domes, and above lava flows
Monitoring of ground displacements difficult
DEM generation difficult!!!
Julia Kubanek – Measuring topographic changes at active volcanoes
General Aim: Development and test of a method to quantify discontinuous deformation, volume changes, and material transport in non-coherent areas
Geodetic Institute 3 01.04.2015
Solution: TanDEM-X TerraSAR-X launched June 15, 2007
TanDEM-X launched
June 21, 2010
Enables DEM generation
Good coherence
Differential DEM analysis
Growing phase Magmatic effusion rate, volume of collapsible
material
1
2 Collapse
topographic changes, redistribution of material along the edifice, fractions of juvenile
and non-juvenile material
Lava flows (and
debris mobilisation)
3 2 Collapse
topographic changes, redistribution of material along the edifice, fractions of juvenile
and non-juvenile material
Two radar images recorded
simultaneously
Repeat interval 11 days
(REUTERS/Dwi Oblo)
Julia Kubanek – Measuring topographic changes at active volcanoes
3
Merapi and Volcán de Colima
Tolbachik
Lava flows (and
debris mobilisation)
V. Yaschuk/KVERT
Geodetic Institute 4
Merapi – Indonesia
Julia Kubanek – Measuring topographic changes at active volcanoes 01.04.2015
Geological setting • Stratovolcano • One of the most active
volcanoes in Indonesia • ~2968 m a.s.l. • Dome-building volcano
2010 Eruption • Explosive eruption on 26 Oct. 2010
destroyed the 2006 lava dome • A phase of rapid dome growth followed • New dome was destroyed again on 4th-
5th Nov. • New dome was built on 6th Nov.
15. Oct. 2010
24. Oct. 2011 04. Nov. 2011
descending
Data overview
Eruption
http://krize.medijskestudije.org
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Merapi – Summit topography
Julia Kubanek – Measuring topographic changes at active volcanoes
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Merapi – Backscatter magnitude
Julia Kubanek – Measuring topographic changes at active volcanoes
24. Oct. 2011 15. Oct. 2010
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Merapi – DEM results
Julia Kubanek – Measuring topographic changes at active volcanoes 01.04.2015
15. Oct. 2010 24. Oct. 2011 04. Nov. 2011 W E
S N
15. Oct. 2010 24. Oct. 2011 04. Nov. 2011
15. Oct. 2010 – 24. Oct. 2011
15. Oct. 2010 – 24. Oct. 2011
24. Oct. 2011 – 04. Nov. 2011
Volumetric change in the summit area
~19 Mio. m3
Pallister et al., 2013, JVGR ~14 Mio. m3
Kubanek et al. 2015, Volumetric change quantification of the 2010 Merapi eruption using TanDEM-X. Remote Sens Environ 164: 16-25.
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Volcán de Colima – Mexico
Julia Kubanek – Measuring topographic changes at active volcanoes 01.04.2015
Geological setting • Stratovolcano located on the Trans-Mexican
Volcanic Belt • 3850 m a.s.l. • Dome-building volcano
Recent eruptive activity • Several phases of dome growth since 1997
• i.e., from 2007 to 2011 • Explosion in June 2011
• Ongoing activity since May 2014
http://img.docstoccdn.com Lava dome, 23. Nov. 2012
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Volcán de Colima – Data
Julia Kubanek – Measuring topographic changes at active volcanoes
08. Jun. 2011 19. Jun. 2011 30. Jun. 2011 11. Jul. 2011 22. Jul. 2011 24. Aug. 2011
TanDEM-X DEM Descending orbit
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Volcán de Colima – Results & Validation
01.04.2015
Mean pre-exp. – mean post-exp.
26. Dec. 2010 – 26. Dec. 2011
Volume change TanDEM-X
~ 200 000 m3
Volume change Photogram.
DEMs
~ 190 000 m3
Photogram-metric DEMs (James & Varley, 2012)
TanDEM-X
Julia Kubanek – Measuring topographic changes at active volcanoes
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Tolbachik – Kamchatka
01.04.2015 Julia Kubanek – Measuring topographic changes at active volcanoes
Geological setting • Located at the southern end of the Kliuchevskaya volcano group • Tolbachik massif is composed of two overlapping, but morphologically dissimilar voclanoes
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Tolbachik
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Eruption in 2012/13 • ~ 9 month from Nov. 2012 till Aug. 2013 • Very fluid lava flows up to 20 km to the South • Development of new cinder cones
Tolbachinsky ´Dol
TanDEM-X DEM, 15.11.2012
Plosky Tolbachik
Ostry Tolbachik
Julia Kubanek – Measuring topographic changes at active volcanoes
http://www.airpano.com
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Tolbachik – Data
01.04.2015 Julia Kubanek – Measuring topographic changes at active volcanoes
09.02.2014
Stripmap
Descending
121.2
-53.5
39.3
0.8
4x4
15.11.2012
Imaging mode Stripmap
Orbit Descending
Effective Baseline 31.6
Height of Ambiguity -210.6
Incidence Angle 39.4
Average Coherence 0.8
Multilooking 4x4
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Tolbachik – Results
01.04.2015 Julia Kubanek – Measuring topographic changes at active volcanoes
15 Nov. 2012
N
N
09 Feb. 2014
N
N
Backscatter magnitude
Phase & Backscatter magnitude
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Tolbachik – Elevation difference
01.04.2015 Julia Kubanek – Measuring topographic changes at active volcanoes
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Tolbachik – 3D Model
01.04.2015 Julia Kubanek – Measuring topographic changes at active volcanoes
Total lava flow volume: 0.56 km³
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Conclusion
TanDEM-X enables to calculate topographic/volumetric changes due to volcanic activity Studies at different testsites proved that TanDEM-X enables to assess topographic changes on a 10 to 100 m level Good additional method to repeat-pass deformation analyses Great potential of TanDEM-X in volcano research
01.04.2015 Julia Kubanek – Measuring topographic changes at active volcanoes
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Contact: [email protected]
Contact: [email protected]
Thank you!
