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25 major crises Infrastructure in 12 countries

2011: VDAP’s 25th Year. ( FY-03-11): 54 infrastructure missions, 12 crisis responses, 15 countries. 25 major crises Infrastructure in 12 countries . 2011: VDAP’s 25th Year. Distal VT’s. Distal VT’s. H 2 S to SO 2. Geodetic trends. EQ patterns ( dVT -LF-hybrid-tremor).

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25 major crises Infrastructure in 12 countries

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  1. 2011: VDAP’s 25th Year (FY-03-11): 54 infrastructure missions, 12 crisis responses, 15 countries • 25 major crises • Infrastructure in 12 countries

  2. 2011: VDAP’s 25th Year Distal VT’s Distal VT’s H2S to SO2 Geodetic trends EQ patterns (dVT-LF-hybrid-tremor) CO2 pulse EQ patterns (dVT-LF-hybrid-tremor) H2O expulsion SO2 drop RSAM trends RSAM trends Cl & F Drumbeats Well levels Magma type & texture Eruption rates (FY-03-11): 54 infrastructure missions, 12 crisis responses, 15 countries • 25 major crises • Infrastructure in 12 countries

  3. The case for a process-oriented guide to forecasting explosive eruptions (at stratovolcanoes)Part 2. Frequently active volcanoes…“Difficult (or easier?) to predict eruptions. Fortunately most are <<VEI 4”John Pallister for the VDAP team (past and present):Randy White, Wendy McCausland, Andy Lockhart, Jeff Marso, John Ewert, Chris Newhall, C. Dan Miller, Rick Hoblitt, John Power, Tom Murray, Dave Harlow, Marvin Couchman, Julie Griswold, Gari Mayberry, Dave Schneider, Steve Schilling, Angie Diefenbach

  4. Tables of common indicators for likelihood and explosivity… based on VDAP experience Don’t try to read this part, I will blow it up! No single indicator is conclusive! Synthesize!

  5. Long-dormant (closed systems): No eruptions in many decades or centuries (e.g., MSH 1980, El Chichon 1982, Pinatubo 1991, Garbuna 2004, Huila 2007, Chaitén, 2008, Sinabung 2010, Vesuvius (0079, 0472,1631), Tambora (2011?)) See McCausland et al. poster for long-dormant systems matrix

  6. But first, some context. 1. Controls on likelihood and explosivity of eruptions 2. Simplified conceptual model of magma ascent 3. Types of frequently-active stratovolcanoes 4. Multi-parameter forecasting guide for frequently-active volcanoes (matrices) 5. Event/probability trees & need for WOVOdat

  7. Complexly inter-dependent variables that control explosivity of eruptions Explosive fragmentation High gas content, high ascent rate & high viscosity = highly explosive (VEI >4) temperature, crystal, gas, & bubble contents) • Very high viscosity = uneruptable magma, intrusion stalls, gas escapes Increasing explosivity Increasing probability of explosive eruption Gas content (saturation, separation of fluid phase, rate of bubble growth) Ascent rate (controlled by gas pressure, buoyancy, path effects*) Most common at long-dormant volcanoes (moderate to large volume closed systems Viscosity (controlled by composition, (e.g., Krakatoa 1883; Katmai 1912, Bezymianny 1956; MSH 1980, Pinatubo 1991; Hudson 1991; Chaitén, 2008; Kasatochi, 2008) • Low viscosity & low to moderate gas content , moderate to high ascent rate = low explosivity • (e.g., basalt shields) Garbuna 2005-06 Increasing gas content, ascent rate, & viscosity * Path effects include strength and permeability of wall rocks (gas loss), tectonic setting and state of stress, etc.

  8. Complexly inter-dependent variables that control explosivity of eruptions at frequently active* (open-system) volcanoes * One or more eruptions in past 1-3 decades Exceptional: High gas, high viscosity, and rapid ascent or unloading: explosive (VEI 3-4+) basalt to andesite explosive eruptions (Merapi, 2010, 1872; Masaya, 1754; also Taal1977, Villarrica 1810, Pichincha, Soputan, 2008, others) temperature, crystal, gas, & bubble contents) Increasing explosivity Increasing probability of explosive eruption Typical: Low gas, high viscosity & slow ascent: typically andesite to dacite low-explosivity (VEI 1-3) domes & spines; & stalled intrusions (Domes: MSH 1981-86, Merapi 1967-2006, SHV 1995-present,, Huila 2008-present, Soputan 2000-2007, Popocatepetl 1995-2005+, Unzen (1991-95), Usu (1910, 1944, 1977-80, 2000), Kelut, 2007; MSH 2004-2008. Stalled intrusions: Garbuna, 2003-04, Taal1987-89, 92, 94, 2004, 06, 07, 11; Cotapaxi, 2001-03, Turrialba2002-present) Spurr2003-05, Three Sisters 1997-2007, Peulik1996-98, Baker 1975, Fuji 2001, many others Viscosity (controlled by composition, Gas content & Ascent rate Increasing gas content, ascent rate, & viscosity

  9. Eruption likelihood & explosivity: “It’s all about volatile loss during ascent” >~70 vol.% bubbles (gas fraction >0.7 = explosive fragmentation) <~70 vol.% bubbles (e.g., 0.1 wt% H2O) vs. Volatile loss during ascent* ~4 wt.% H2O (dissolved) • ~4 wt.% H2O • (dissolved) * Volatile loss = crystallization & increased viscosity. Requires permeable magma (fractures, foam), & permeable wall rocks, and/or convection w/in conduit

  10. Frequently erupting “Open-Systems” (Hot pathways for gas & magma ascent. Most eruptions smaller than at long-dormant) 3. Degassed dome & spine extrusions 1. Wide open 2. Semi-steady state dome extrusions Mostly basaltic to basaltic andesite, e.g., Stromboli, Etna, Soputan since 2007, Mayon, Fuego, Arenal, Villarrica, Pavlof, Shishaldin, etc. e.g., Merapi since 1968, Karangetang since 1970? Santiaguito since 1922, Popo since 1996, Bezymianny since 1956 Huila since 2008 e.g., MSH 2004-08, Kelut 2007 Continuously open conduit; filled with low viscosity magma; gas escapes at shallow levels and through Strombolian eruptions; shallow crystallization may produce viscous magma & Vulcanian eruptions Conduit mostly open; gas partly escapes during ascent; & magma viscosity increases, may occasionally solidify at shallow levels. Larger or more gas-rich magma batches produce Vulcanian eruptions Conduit only open at depth; shallow levels solidify; most gas escapes during ascent, produces high-viscosity degassed magma

  11. Long-dormant volcanoes provide context for evaluating frequently active systems Typical progression in earthquake types (long-dormant systems) 3. Volcanic tremor (+/- hybrids) 2. Shallow: H2S, SO2, Cl & deformation 2. LF Low-frequency earthquakes, explosions, + hybrids Regional fault 1. Deep: CO2, deformation, recharge? 1. HF Volcano-tectonic (dVT & VT’s); +/- DLPs Pinatubo examples

  12. Rio Simbola Rio Páez ■ Belalcázar 0 15 km Real-time tools for analysis and forecasting RSAM - Real-time Seismic Amplitude Measurment Example from Volcan Huila, Colombia; courtesy of INGEOMINAS Long dormant before 2007; frequently active dome extrusion since 2008

  13. Tables of common indicators for likelihood and explosivity… based on VDAP experience Don’t try to read this part, I will blow it up! No single indicator is conclusive! Synthesize!

  14. Open (frequently active) systems: Repeated eruptions during the past 1-3 decades “Eruption Possible”

  15. Open (frequently active) systems: Repeated eruptions during the past 1-3 decades “Magmatic eruption likely” VEI 3 eruption of Soputan, 6 June 2008 10-minute RSAM Little time for warning Calendar date

  16. Open (frequently active) systems: Repeated eruptions during the past 1-3 decades “Low-moderate VEI” (e.g., VEI 2-3) 2008 microcrystalline basalt from VEI 2 eruption of Soputan (can be more explosive with higher gas)

  17. Open (frequently active) systems: Repeated eruptions during the past 1-3 decades “High VEI” (e.g., VEI 4 “100-year” eruptions) To 4 Nov. Merapi 14 Oct.

  18. Open (frequently active) systems: Repeated eruptions during the past 1-3 decades • “High VEI” (e.g., VEI 4 “100-year” eruptions) 2010 Merapi basaltic andesite block

  19. Open (frequently active) systems: Repeated eruptions during the past 1-3 decades

  20. Key differences in eruption & explosivity indicators at frequently-active vs. long-dormant volcanoes • Frequently-active volcanoes have: • “Leaky” hot pathways (conduits, fractures) for gas and magma ascent – this typically translates into: • History of mainly small to moderate VEI eruptions (vs. large PF sheets) • More rapid progression from heightened unrest to eruption • Lower M seismicity (e.g., <M4 vs. >M4) & lower RSAM • Missing seismic types (e.g., VT’s) possible compared to common long-dormant sequence (DVT & VT – LF – Hybrid – Tremor) • Deformation mainly shallow & more localized • Gas dominated by shallow- (Cl, F, SO2) vs deep (CO2) degassing species (unless “100-year” eruption) • Quick progression from scrubbed (H2S) to dry (SO2) species • Generally more mafic magmas; many lack hydrous minerals(Thin- or un-rimmed hydrous minerals indicate rapid ascent & larger-than-normal eruption) • Often “top driven,” e.g., small dome collapse unloads & triggers larger eruptive phase … (vs. large summit/flank collapse trigger for long-dormant)

  21. Integrating Event Tree & Monitoring Data “High VEI” Merapi Example

  22. 1930 style collapse 10% 1872 style collapse 4% • Basis for probability estimation, Merapi, v. 2, 06/26/2006 • Conceptual background is in plain type; reasoning behind specific numbers on the tree is in italics. • Node 1: Magma at the surface • (i.e., 100%). Merapi already woke up from a roughly 5 year sleep, so we can just use 1.0 (100%) as the probability in this tree. • Node 2: Extrusion rate >100,000, 10-100,000, < 10,000 /d • 100% for >100,000/day, based on estimates as of 5/14/06 (volume of the dome) and again on 5/20-5/23/06 (combination of dome growth and rate of rockfall and pyroclastic flow deposition in Kali Bedog). As of 6/20 and probably still as of 6/22, the extrusion rate is approximately 210,000 m3/d, of which 75,000 m3/d is growth of the lava dome and about 130,000 m3/d is in rockfalls and awanpanasguguran (160,000 m3/d x 0.8 DRE correction, based on PLAZ seismic calibration). This has risen slightly from the 150,000-175,000 m3/d estimated at the end of May. • Extrusion rate is known to be a significant factor in the stability of lava domes, for four reasons: • high extrusion rate creates high shear strains in the carapace of the dome • it creates more weak, soft material in the core of the dome • any extrusion, especially at a high rate, causes loading of rocks beneath the dome and causes dome fronts to oversteepen • high extrusion rates favor incomplete degassing of the rising magma column, with the effect that internal gas pressures can build unless there is efficient degassing (pressure bleed). There is an implicit assumption here that original gas content of Merapi magmas is constant, so variability in gas content of magma reaching near the surface depends on magma ascent rate or its measurable proxy, magma extrusion rate. However, an apparent increase in SO2 emission beginning on June 13 (OMI data) without significant increase in extrusion rate suggests that there might also be an increase in concentration of gas in the magma. We don’t have a specific node for gas concentration in magma but it is indirectly included in Node 3 (gas pressures) if the supply rate of gas exceeds the magma’s capacity to bleed off that pressure. • The basis for estimating extrusion rate = rate of growth of lava dome + rate of accumulation of pyroclastic deposits, e.g., endapanawanpanas, guguran. • The long term eruption rate for Merapi was estimated by Siswowidjoyo, Suryo, and Yokoyama (Bulletin of Volcanology, v. 57) as 1.2 million cubic meters per year, or approx 3300 m3/d. Their estimate does not include collapsed material (pyroclastics) – only volumes of lava domes – so it is probably underestimated by a factor of 2 or 3. So, we defined 3 branches here, 0-10,000; 10000-100000; and >100000 m3/d, equivalent in words to “normal,” “active (1990’s style), and “very active” Scenario Duration of the crisis (for annualization of risk, assume duration = 1 year) #1, #2 and #3 1 New dome + sm. Collapses Near-surface gas pressure 8% 60% 2 Increasing #4=1930-scale collapse 4% 4% 14% 20% 30% 3 #5 1872 expl eruption 1% 1% Magma supply rate 10% Increased #1, #2 and #3 70% New dome + sm. collapses 70% 48% constant or decreasing 85% #4 1930-scale collapse 6% 6% 56% 80% 10% #5 1872 expl eruption 3% 3% 5% #1, #2 and #3 New dome + sm. Collapses 10% Fluctuates slightly 87% (2nd boiling, release) #4 1930-scale collapse 12% 1% 60% 10% #5 1872 expl eruption This includes 2nd boiling, Volcano restless constipation/breakthrough scenario 0% small explosive events. 3% ~Constant (self-sealing) #1, #2 and #3 100% 20% 20% New dome + small collapses 8% 95% ~ Constant #4 1930-scale collapse 8% 0% 40% 5%

  23. 2010 Merapi: Satellite radar = high initial extrusion rate & high probability of large eruption North Eruption Scenario Probabilities (with magma pressure: Increasing : Constant : Decreasing) Extrusion Rate (m3/s)1990’s type1930, 1961 type1872 type >1.2 73:83:93 15:10:5 10: 5: 1 0.12 – 1.2 83:90:87 10:5: 2 5: 2: 1 <0.12 m3/s 85:80:70 5: 0: 0 0: 0: 0 VDAP-CVGHM Event Tree (2006) 2010 extrusion rate 10 X 2006 “The (2006) extrusion rate of ~210,000 m3/d as estimated on 6/20/06, or 2.4 m3/s, is high by Merapi standards and matched within the 20th century only in 1930 and 1961, and perhaps briefly in the first week of the 1992 eruption. Both times, the high rate seems to have contributed to large eruptions.” (VDAP-CVGHM Event Tree, 2006) DLR, German Aerospace Center, 2010 • 31 Oct- 4 Nov: ~5 Mm3 dome grows in crater at ≥25 m3s-1; constant MM2-3 tremor (25 km) • 4 Nov.: CVGHM extends evacuations to 20 km – saves thousands of lives • 5 Nov. 00:05: Largest eruption (VEI 4) – ash cloud to 55,000’, pyroclastic flows to 15 km • International response- Indonesia, Europe, US, Japan

  24. The next frontier: relating individual event types to detailed processes Iverson et al. 2006 Pallister et al. 2008

  25. Checklist of questions to pose and attempt to answer before making a forecast (Part 1 – Geologic context) What does geology and petrology say about past eruptions & hazards? • Long-dormant or frequently active? • Frequency, size, and explosivity of past eruptions? (VEI range?) • Size and character of deposits: Ash flow sheets vs. lava flow, domes & dome-collapse pf’s?, extensive lahars? • Structure of the edifice? (e.g., stratovolcano? shield? caldera?) • Stability of the edifice: steepness, structural weaknesses, evidence of past collapse, relation to regional tectonics? • Nature of past eruptions • Explosive vs. non-explosive vs. fumarolic? • Previous “outsized” eruptions ? • Composition and character of previous juvenile components? • Vesicular or dense? • Bulk rock and glass compositions (basalt-andesite-dacite-rhyolite)? • Presence and condition of hydrous phases (e.g., amphibole & micas, reaction rims?). Other indicators of high PH2O or SO2 (e.g., cummingtonite, anhydrite) • Extent of fragmentation (e.g., “gray pumice”) • Areas affected and population at risk? (Hazard assessment!)

  26. Checklist of questions to pose and attempt to answer before making a forecast (Part 2a – Monitoring data) • Character of the current unrest? • Seismic: • RSAM (seismic energy trend)? • Type, magnitude and frequency of events (VT, LF, VLF, DLF, hybrids, explosion signals, tremor)? • Character and duration of events (e.g., distal-proximal VT’s, spasmodic bursts, continuous or banded tremor, LF’s or tornillos)? • Comparison to background seismicity • Nature of installations (how well-coupled, oriented, distance from vent) • Comparison to previous episodes and/or to analogous unrest at other volcanoes? • Deformation: • Inflation, deflation, and/or lateral? • Rate… and rate of change? • Deep? Shallow? Large-volume? Small-volume?, Geometry? • Comparison to previous episodes and/or to analogous unrest at other volcanoes?

  27. Checklist of questions to pose and attempt to answer before making a forecast (Part 2b – Monitoring data) • Gas: • Emission levels, ratios and trends of: SO2, CO2, H2S, Cl, F, any other species? • Likelihood of groundwater “scrubbing” (conversion of SO2 to H2S)? • Hot? dry? pathway to the surface? • Conduit plugged by hydrothermal or solidified cap? • Comparison to emissions during previous episodes? • Observations (including remote sensing) • Morphologic changes (e.g., fractures or other structures)? • Character of Initial explosions/extrusions and any associated tephra? Groundwater changes? • Vegetation changes? (e.g., tree-kills?) • Comparison to previous episodes and/or to analogous unrest at other volcanoes?e.g., “ What proportion of previous volcanoes that exhibit the observed indicators continued to magmatic eruption and how big (VEI)? • Event-probability tree? • This is why we need WOVOdat! • -END-

  28. Real-time tools for analysis and forecasting – associating event types with processes Typical progression in earthquake types Plus Hybrids of HF & LF Original signal Low pass filtered 3. Volcanic tremor and Spectrogram 2. LF Low-frequency earthquakes Power Spectrum 1. HF Volcano-tectonic earthquakes (distal vs. proximal) Hybrid (VLF + HF) volcanic earthquake: represents rock breaking & magma or fluid transport

  29. Open (frequently active) systems: Repeated eruptions during the past decade Conduit never freezes: e.g., basaltic & basaltic andesite systems like Stromboli, Etna, Soputan, Mayon, Fuego, Arenal, Villarrica, Telica, Llaima, Masaya 1970-1990, Mayon, Pavlof, Shishaldin and semi-steady state andesite to dacite dome extrusions like Santiaguito, Merapi, Karangetang, Huila since 2008, Popocatepetl since 1996, Colima since 1997, SHV since 2000 in which magma supply just enough to keep magma rising; occasional larger than normal influx or gas-rich influx drives more explosive eruption (e.g., Merapi 2010) may also be driven by “top down” processes (e.g., dome-collapse unloading as in Boxing Day 1997 eruption at SHV; summit dome collapse at Soputan in 2007-08)

  30. Long-dormant (closed systems): No eruptions in many decades or centuries (e.g., MSH 1980, El Chichon 1982, Pinatubo 1991, Garbuna 2004, Huila 2007, Chaitén, 2008, Sinabung 2010, Vesuvius (0079, 0472,1631), Tambora (2011?))

  31. What kind of eruption? What to expect next How big? Tephra Quantifying forecasts: Use of Event & Probability Trees at Garbuna, PNG Current Status

  32. Areas affected Probability Trees – Lessons from MSH, Garbuna, Merapi, Huila, Lunayyir • Internal observatory use valuable • Focuses scientists’ thinking • Illuminates alternate viewpoints & uncertainties • Aids in reaching consensus • External: Use with care - requires user education • Written explanations & scientific background essential (i.e., meta-data required!) • For well-studied & well-monitored volcanoes nodes can be linked to measurable parameters ! cloud Tephra cloud Vulnerability & Risk

  33. Augustine, 2006

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