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On the border betweengeothermal and volcanology
PHILIPPE JOUSSET
Geothermal Power Plant Electricity and heating
Volcano eruptingScience, hazard and risk
(Merapi 2010, discovery.com)
Players
Inspired by Olafur Flovenz (Isor)
Geothermal Power Plant Electricity and heating
Volcano eruptingScience, hazard and risk
(Merapi 2010, discovery.com)
What characterize
s each?
Inspired by Olafur Flovenz (Isor)
Geothermal Power PlantElectricity and heating
Inspired by Olafur Flovenz (Isor)
Profit driven (Business)Need • to secure, expand and manage production• public acceptance• reliable information (provided by scientists)• quick info and results when they decide
Poor knowledge about research methods, advantage/limitations and time-span required
Volcano eruptingScientists, hazard and risk
No profit but need money (public and more).Driven by scientific interest and public safetyJudged by scientific publications and reports.Main interest: beauty of Science
Do not understand the rush for results among the industries.
Problems with explaining science and research methods to industry and public.
Verticalcomponent
5 s5 s
Verticalcomponent
Wayang Windugeothermal field, West Java,Indonesia
Merapi volcanoEarthquake prior to large eruption (2010)
5 s5 s
<=>
Jolly et al., 2012, JVGR 215-216 (2012) 26–39
Main scientific objectivesStructure and dynamics of volcanoes, hydrothermal and
geothermal systems from integrated informationStructureTo find where the productive fractures are located (depth, fluid temperature and composition, …),– Seismic wave analysis: velocity models, anisotropy, …– Resistivity distribution: temperature, mineral content, …– Integrated methods: require rock petrology, fluid content, …
DynamicsTo draw and interpret links between– Exploitation of the geothermal system/volcanic activity– Changes in continuously monitored geophysical parameters
Main practical questions for the geothermal industry
• Where are the (very) hot fluids?• How do they move?• How should industry exploit them for being sustainable?
Þ Signatures on geophysical data (e.g., seismic velocities/ratio)
Þ Probe the reservoir and its suroundings
• Earthquake activity related methods1. Travel time tomography
• Vp model inversion: rock type• Vs/Vs ratio: fluid content and type
• Seismic ambient noise cross-correlation methods2. Ambient noise tomography3. Reflectivity tomography4. Coda-wave and noise interferometry
Passive seismic methodsfor imaging structure and processes
Veðurstofa Íslands
Krafla
Hengill
SvartsengiReykjanes
IMO
Passive seismics tomography(Tryggvason et al. 2003)
Hengill
SvartsengiReykjanes
GIPP/DEPAS
• Earthquake detection and analysis Seiscomp and matlab algorithmsApril 2014 – August 2015: >2000 events (P and S waves picks)
• Non-linear a priori localisation• 1D velocity model – Velest (Kissling et al., 1994)• 3D velocity model – Simulps (Thurber, 1986)
• Vp• Vp/Vs ratio
Travel time tomography
SIL model
IMAGEModel
1D Vp model2050 events
(P and S picks)
2014 2015
Ray paths
3D Vp model2050 events
(P and S picks)
W E3D Vp model2050 events
(P and S picks)
3D Vp model2050 events
(P and S picks)
Reykjanes tip
3D Vp model2050 events
(P and S picks)
Reykjanes tip
Integration of methods -> better understanding
Figure from Friðleifsson et al., Geothermics 49 (2014) 119–126
Vp/Vs ratio2050 events
(P and S picks)
Vp/Vs ratio2050 events
(P and S picks)
Subsidence~7-9 cmInSAR
2005-2008
2014-2016Still going on
(Friðleifsson, personal communication;
Sigmundson, poster)Keiding et al, 2010, Fig. 5c
CALL FOR PAPERS
Journal of Volcanology and Geothermal ResearchSpecial Issue: Reykjanes, IcelandStructure and dynamics ofMid-Oceanic Ridges geo/hydrothermal systems
• Structure and magmatic processes at mid-oceanic ridges• Exploration and exploitation of hydrothermal systems
• Observations and modelling• Geology, physics and chemistry of rocks and fluids
Editor in chief: Jürgen Neuberg (University of Leeds)Editors:
Philippe Jousset (GFZ) – [email protected] Kaergaard Mortensen (Reykjavik Energy) - [email protected]án Ágústsson (ÌSOR) - [email protected]. Magnus Tumi Guðmundsson (University of Iceland), [email protected]ðmundur Ómar Friðleifsson (HS Orka) - [email protected]
Impact Factor: 2.674
The geothermal industry is different from the oil and gas industry – opportunity for volcano scientists Our task as researchers is to develop cheap and reliable exploration method that the geothermal industry can afford.◦ integration of scientific methods that come from different
horizons (volcanology, physics, chemistry, …)◦ use of novel technologies for better knowledge of structure and
mechanisms. EU is supporting our R&D projects to advance the development of geothermal energy for benefits of the society.
Inspired by Olafur Flovenz (Isor)
Concluding remarks The border is fading – good news!• The Earth is the same, the objectives similar Future resides in excellence and education, though ambitious projects:• Krafla Magma Testbed • Training for future generation
FUTURE DIRECTIONS Exploration and monitoring
◦Denser acquisition array◦Accurate time measurement◦Cheap technology
Example DAS technology
• IMO 23.03.2015 16:07:08.53• Depth: 3.563 km• Magnitude: 1.02Ml• Location: Beneath Cable
P-WaveS-Wave
1 s
>12 km
EAGE/DGG Workshop onFibre Optic Technology
in Geophysics
www.eage.org
FIRST ANNOUNCEMENT & CALL FOR ABSTRACTS
3 1 March 2017Potsdam, Germany
Technical CommitteePhilippe Jousset Chairman (GFZ Potsdam)Thomas Reinsch (GFZ Potsdam)Jan Henningens (GFZ Potsdam)Charlotte Krawczyk (T.U. Berlin)
FUTURE DIRECTIONS: monitoring
Monitoring of fluid and magma movements• Multiparameter stations including superconducting
gravity meters• Deployed at volcanic site (Etna)• To be deployed at geothermal site
iGrav (GWR) superconducting gravity meter
• Better performances over the whole spectral band over other kind of gravity meters, especially spring gravity meters. • Badly controlled instrumental drift of spring gravity meters a critical point preventing the study of long-term gravity changes as compared with the superconducting gravity meter records.
Takk fyrir! Drilling at Reykjanes, March 2015pic by Thomas Reinsch, GFZ
Players in the game(s)…
Developers.Investors /Operators /Owners.Financing institution (banks, funds).Service companies (engineering, drilling, etc).Manufactures.
Local and national authorities.Public.Environmental organizations.Research institutions and universities
Local and national authorities.Public.Environmental organizations.Research institutions and universities
Geothermal developmentand industries
Volcanology and volcanic risk management
Inspired by Olafur Flovenz (Isor)
• repetitious earthquakes beneath Ngauruhoe volcano (2005–2010)• constrain the source geometry of these earthquakes by inverting waveforms for
the source location, geometry and orientation. • The inversion and error analysis shows that a steeply dipping crack at a single
source position is the preferred model for the trigger mechanism.• Conceptual model for Ngauruhoe earthquakes including a trigger mechanism
caused by periodic excitation of an over-pressurized cavity system, and a post trigger resonance and scattering mechanism produced by a two phase gas–water or gas–steam mixture.
• We explain the spectral evolution through changes in the volume fraction of bubbles within a resonating and scattering cavity system affecting velocity, impedance contrast, and frequency contents.
Vp/VsResistivityand faults
Depth2.9 km
HENGILL, Iceland
Integration of parameters
Jousset et al., 2011, Geothermics
Vp/VsResistivityand faults
Depth2.9 km
HENGILL, Iceland
Integration of parameters
Jousset et al., 2011, Geothermics
Classes are then mapped back to space
HENGILL, Iceland
Jousset et al., 2011, Geothermics
Interpretation
Class 9 (low resistivityHigh VP/VS ratio)suggests the existence of supercritical fluids at depth below Hengill volcano.
HENGILL, Iceland
Jousset et al., 2011, Geothermics
