Understanding magmatic processes and seismo-volcanic source localization with multicomponent seismic arrays Lamberto Adolfo INZA CALLUPE Thesis Defense May 30th, 2013 Supervisor: Jer´ omeˆ MARS Gipsa-Lab, INP Grenoble Co-supervisors: Jean-Philippe METAXIAN´ ISTerre, Chambery´ Christopher BEAN UCD Earth Institute, Ireland Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 1/50 Volcanoes Millions of people are at risk from volcano hazards along the Andes (Tilling 2009) 2 major volcanic events: Nevado del Ruiz VEI 3 (1985) and Huaynaputina VEI 6 (1600) (VEI = volcanic explosivity index from 0 to 7) Seven active volcanoes in southern Peru Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 2/50 Misti volcano - 5822 m (Altitude) EL MISTI the most dangerous volcano Misti volcano: Lat -16.3 Lon: -71.4 Alt: 5822 m Arequipa city, the 2nd most important of Peru, 17 km away south-west of Misti crater Arequipa: more than 1 million inhabitants A telemetry seismic network of 5 stations around Misti volcano Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 3/50 Ubinas volcano - 5672 m (Altitude) UBINAS the most active volcano Ubinas crater: Lat:-16.3 Lon:-70.9 Alt:5672 m An andesitic stratovolcano, more than 5000 people living within 12 km from the crater 23 eruptions between 1550 - 1899 10 eruptions between 1906 - 1999 Eruption rate: 7 per century (Thouret et al 2005 Last eruption: 2006 - 2009 Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 4/50 Classical seismic network in Ubinas Seismic activity dominated by volcanic earthquakes (explosive, LP, tremors events) This type of signals are different of normal earthquakes (Waveforms with emergent onset, unclear P and S seismic phases) Traditional means do not work his type of signals, they cannot be localized New methods needs to be developed Ubinas eruption is characterized by vulcanian style (short-duration highly explosive and destructive). Last eruption produced ash columns of 3 km, and ashfall was reached 20 Seismic network is a group of seismometer to monitoring km away the volcano. the volcano Ubinas: 4 seismometers, short-band response (1Hz), single component (vertical) since 2006, Old technology Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 5/50 Outline 1 Introduction 2 Source Localization 3 Application and Interpretation 4 Conclusions and perspectives Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 6/50 Plan 1 Introduction 2 Source Localization How to study Ubinas volcano? New instrumentation 3 Application and Interpretation Experiment Ubinas 2009 4 Conclusions and perspectives Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 7/50 How to study Ubinas volcano? 8196 NUBI 4600 4800 4800 Two seismic antennas (NUBI and UB2 WUBI). 8194 Using three component (3C) 5000 5000 UB3 UB1 seismometers. 5200 4800 WUBI 5400 Goal: Extract information of wave 5400 fields to understand magma LATITUDE (UTM KM) 5400 mechanisms 8192 4800 5200 Seismic array can measure an important vector consist of 4400 5000 4600 slowness, back-azimuth and 4800 incidence angle 8190 UB4 294 296 298 300 LONGITUDE (UTM KM) Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 8/50 State of the art 1C/3C Author Method Volcano Saccorotti & Del Pozzo (2000) 1C-antennas Stromboli (Italy) Metaxian et al (2002) 1C-antennas Arenal (Costa Rica) Almendros et al (2001b) 1C-antennas Kilauea (USA) La Rocca et al (2004) 1C-antennas Stromboli (Italy) Di Laito et al (2007) 1C-antennas Etna (Italy) Earthquake depths related to magma transport were not clearly estimated from array data. Locating the magma depth is crucial to understand eruptive mechanisms. Chouet et al 2003 and 2013 highlight the evolution of broadband 3C-seismometers Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 9/50 New instrumentation Band width: 0.03 - 50 Hz Three component with broadband sensors. High dynamic range with 24-bit digitizer. Wireless communication capabilities (WiFi) Compact with very low power consumption Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 10/50 Experiment Ubinas: May - July 2009 4600 8196 NUBI 4400 4800 NUBI: 10 instruments (Guralp a) 6TD and 3EPS) 4600 8194 WUBI: 12 instruments (Guralp 5000 5000 6TD and Titan-Neomax) WUBI 5200 Sensor distance: around 50m, 5400 4800 4800 aperture seismic array: 300m 5400 Latitude Km Altitude: NUBI at 4632 m high and WUBI 4732 m 8192 5400 5200 Distance: NUBI 3750 and WUBI 2567 m away the crater 4600 4400 Extreme environment range 5000 4200 between, -10 Celsius, high 4800 altitude. 8190 b) 294 296 298 300 Longitude Km Experiment supported by: IRD, UCD, IGP Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 11/50 Experiment Ubinas: May - July 2009 NUBI: 10 instruments (Guralp 6TD and 3EPS) WUBI: 12 instruments (Guralp 6TD and Titan-Neomax) Sensor distance: around 50m, aperture seismic array: 300m Altitude: NUBI at 4632 m high and WUBI 4732 m Distance: NUBI 3750 and WUBI 2567 m away the crater Extreme environment range between, -10 Celsius, high altitude. Hard work Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 11/50 Ubinas seismic activity wubi.z 2009.06.03 filt=1.000hz − 5.000hz wubi.z 2009.06.14 filt=1.000hz − 5.000hz 0h 0h 1h 1h 2h 2h 3h 3h 4h 4h 5h 5h 6h 6h 7h 7h 8h 8h 9h 9h 10h 10h 11h 11h 12h 12h 13h 13h 14h 14h 15h 15h 16h 16h 17h 17h 18h 18h 19h 19h 20h 20h 21h 21h 22h 22h 23h 23h 0 10 20 30 40 50 60 0 10 20 30 40 50 60 time (min) time (min) Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 12/50 Seismic waveforms on Ubinas -9 100 -9 100 20090614 1215 EXP 10 20090613 1325 EXP 10 50 50 0 10-12 0 10-12 -50 -100 -50 10-15 10-15 -150 -100 10-9 150 10-9 20090605 0039 EXP 50 20090610 0731 EXP 100 -12 50 10-12 0 10 0 -50 -50 10-15 10-15 -100 3 20090528 1345 LP 20090621 0231 LP 6 10-12 10-12 3 0 0 -3 10-15 -3 10-15 100 -9 10 20090707 0519 LP 20090524 1526 VT 10 5 50 10-12 0 0 10-12 -5 -50 10-15 -15 -10 -100 10 60 10-9 20090603 2106 HYB 16 20090604 1506 HYB 30 8 10-12 10-12 0 0 -30 -15 10-15 -8 10 -60 20090624 0528 TRE 20090602 1017 TOR 3 3 10-12 10-12 0 0 -3 -15 10-15 -3 10 0 15 30 45 60 75 0.1 1 10 0 15 30 45 60 75 0.1 1 10 Sec Hz Sec Hz Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 13/50 Global activity on Ubinas - RSEM 12 35 1 7 8 9 8 10 11 24 6 4 Based on RSEM method (De la 0 logRSEM Cruz Reyna and Reyes Davila -4 et al 2001) on 1C vertical 24 31 7 component. May June 12 More than 400 LP, 16 14 15 explosions, several hours of 8 12 13 16 tremors events manually 4 selected and compared with 0 IGP catalog logRSEM -4 Inverted triangles represent vulcanian explosions 7 14 21 June Dashed lines represent tremor Antenna: WUBI 24-May-2009 to 20-Jun-2009 events 1 Black squares represent t=iT + T 2 2 subduction earthquakes 1 2 RSEM(iT ) = log ∑ y (t) T t=iT T − 2 Realtime Seismic Energy Measurement Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 14/50 Global activity on Ubinas - RSEM 12 8 4 Based on RSEM method (De la 0 logRSEM Cruz Reyna and Reyes Davila -4 et al 2001) on 1C vertical component. 21 28 5 June July 12 More than 400 LP, 16 explosions, several hours of 8 tremors events manually 4 selected and compared with 0 IGP catalog logRSEM -4 Inverted triangles represent vulcanian explosions 5 12 July Dashed lines represent tremor Antenna: WUBI 21-Jun-2009 to 14-Jul-2009 events 1 Black squares represent t=iT + T 2 2 subduction earthquakes 1 2 RSEM(iT ) = log ∑ y (t) T t=iT T − 2 Realtime Seismic Energy Measurement Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 14/50 Plan 1 Introduction 3 Application and Interpretation 2 Source Localization 4 Conclusions and perspectives Small aperture seismic array Formulation for 1C and 3C MUSIC-3C algorithm Application on synthetic data Comparison between 3C and 1C Source localization Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 15/50 Small aperture seismic array Array Response Function 15 10 5 0 Ky 1/km −5 −10 −15 Slowness vector: −15 −10 −5 0 5 10 15 Kx 1/km cos(θ)sin(φ) 1 − u(θ,φ) = sin(θ)sin(φ) v − Multicomponent sensor: 3C seismometers a cos(φ) sense full seismic waves − Irregularly sensor spacing array due to the va is the apparent velocity volcano topography (dn < λmin/2) Delay: τn = dn u(θ,φ) · Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 16/50 Formulation for single component (1C) Signal received by one-component sensor Wn(f )= S(f )exp( j2πfsτn)+ Bn(f ) − Antenna output in matrix form W(f)= A(θ,φ)S(f )+ B(f) Steering vector 1 exp( j2πfs (d2 u)) A(θ,φ)= − · ... exp( j2πfs (dn u)) − · Cross-spectral matrix H ΓW = ξ W(f)W (f ) ξ H . is the expectation operator, (.) is the conjugate Direction of arrival algorithms transpose operator Conventional methods (Beamforming Capon), Γ θ φ ξ H H θ φ σ2 Subspace-based methods (ESPRIT, MUSIC) W = A( , ) S1(f )S1 (f ) A ( , )+ bI Maximum-likelihood Methods (Deterministic, σ2 Noise is spatially white with variance b, I=Identity Stochastic) matrix Adolfo INZA ( Thesis Defense ) Seismo volcano source localization May30th,2013 17/50 Extension to three components (3C) Given a time series window 3C Data of the one-snapshot, N=number of sensors X Y Z 1,m 1,m 1,m W3Cm(f )= ..