PHIVOLCS DOST

MARITON V. BORNASMARITON V. BORNASPhilippine Institute of Volcanology & Seismology (PHIVOLCS)Philippine Institute of Volcanology & Seismology (PHIVOLCS)

Department of Science & Technology (DOST)Department of Science & Technology (DOST)

UNDERSTANDING UNDERSTANDING

VOLCANOES & VOLCANOES &

VOLCANIC HAZARDSVOLCANIC HAZARDS

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What is a What is a VOLCANOVOLCANO??

�� a vent, hill or mountain from w/c molten or hot rocks w/ a vent, hill or mountain from w/c molten or hot rocks w/

gaseous material are ejectedgaseous material are ejected

�� also craters, hills or mountains formed by removal of prealso craters, hills or mountains formed by removal of pre--

existing material or by accumulation of ejected materialsexisting material or by accumulation of ejected materials

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1965 Taal Volcano eruption explosion 1965 Taal Volcano eruption explosion

crater (1.5 X 0.3 km wide) & cinder cone / crater (1.5 X 0.3 km wide) & cinder cone /

tuff ring (68.5 m high, 170 mtuff ring (68.5 m high, 170 m--wide rim)wide rim)

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Where do Volcanoes Form?Where do Volcanoes Form?

ContinentalContinental

ArcArc

MagmaMagma

HotspotHotspotMidMid--OceanicOceanic

RidgesRidges

IslandIsland

ArcArcRiftRift

ZonesZones

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Why do we have VOLCANISM?Why do we have VOLCANISM?HEAT WITHIN EARTHHEAT WITHIN EARTH’’S INTERIOR DUE TO:S INTERIOR DUE TO:

1.1.LONGLONG--LIVED RADIOACTIVITYLIVED RADIOACTIVITY

��235235U, U, 238238U, U, 232232Th, Th, 4040KK

2.2.ACCRETIONARY HEATINGACCRETIONARY HEATING

��Billions of years of impacting bodies (meteors, comets) Billions of years of impacting bodies (meteors, comets)

that imparted kinetic energy, converted into frictional that imparted kinetic energy, converted into frictional

heating w/in the earth heating w/in the earth

3.3.CORE FORMATIONCORE FORMATION

��release of potential energy as the core sinksrelease of potential energy as the core sinks

4.4.TIDAL HEATINGTIDAL HEATING

��Moon raises 11 cms/year of Moon raises 11 cms/year of ““tidestides”” in the mantle in the mantle

equivalent to ~ 3.0x1019 J/yr; similar heating in IOequivalent to ~ 3.0x1019 J/yr; similar heating in IO

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Classification of Volcanoes (PHIVOLCS)Classification of Volcanoes (PHIVOLCS)

ACTIVE:ACTIVE:

��erupted w/in historical times (last 600 yrs); has historical erupted w/in historical times (last 600 yrs); has historical

traditional accounts, written or oraltraditional accounts, written or oral

��erupted w/in geological times (erupted w/in geological times (≤≤10,000 yrs)10,000 yrs)

POTENTIALLY ACTIVE POTENTIALLY ACTIVE

��landform is younglandform is young--looking but w/ no records of eruptionlooking but w/ no records of eruption

INACTIVEINACTIVE

��no recorded eruptionsno recorded eruptions

��longlong--period inactivity is evident from too much weathering period inactivity is evident from too much weathering

& erosion of deep & long gullies (valleys)& erosion of deep & long gullies (valleys)

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Active, Inactive & Active, Inactive &

Potentially Active Potentially Active

Volcanoes of the Volcanoes of the

PhilippinesPhilippines

Setting: Island ArcSetting: Island Arc

�� 300 volcanoes300 volcanoes

�� 22 considered active22 considered active

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Active Volcanoes in the PhilippinesName No. of

Eruptions Date of Last Eruption

LAT/LONG Location

Mayon � 49 2006 13° 15.4'/123° 41.1' Albay, Bicol Region, Luzon

Taal � 33 1977 14° 00'/121° 00' Batangas, Luzon

Canlaon � 22 1996 10° 24.7/123° 7.9' Negros Occidental, Visayas

Bulusan � 14 2006 12° 47'/124° 03' Sorsogon, Bicol Region, Luzon

Ragang 9 1915 7° 41.5/124° 30.3' Bukidnon, Mindanao Smith 6 1924 19° 32.5/121° 55' Cagayan, Northern Luzon

Hibok-Hibok � 8 1949-1953 9° 12.2/124° 40.4 Camiguin Island, Mindanao

Didicas 6 1978 19° 05'/122° 12' Cagayan, Northern Luzon

Pinatubo � 3 1991 & 1992 15° 08'/120° 21' Pampanga, Zambales & Tarlac, Luzon

Babuyan Claro 3 ?1913 19° 31.5'/121° 57' Cagayan, Northern Luzon Bud Dajo 2 1897 5° 59'/121° 13' Sulu, Mindanao Camiguin de Babuyanes 1 1857 18° 50'/121° 52' Cagayan, Northern Luzon Cagua 1 1860 18° 13'/122° 07' Cagayan, Northern Luzon

Banahao � 1 ?1730 14° 04'/121° 29' Laguna & Quezon Province, Luzon

Calayo (Musuan) 1 1866 7° 52'/125° 4.4' Bukidnon, Mindanao Iraya 1 1464 20° 29'/122° 01' Batanes Island, Northern Luzon Iriga 1 ?1628 13° 28'/123° 28' Camarines Sur, Bicol Region,

Luzon Biliran ? ?1939 11° 37'/124° 30' Leyte, Visayas

Matutum � 1 ?1911 6° 22'/124° 04' South Cotabato, Mindanao

Parker � 1 1641 6° 6.8'/124° 53.5' South Cotabato, Mindanao

Makaturing ? ?? 7° 38.5'/124° 19' Lanao, Mindanao Leonard 1 1,800 Bp 7° 4.5'/126° 4' Davao, Mindanao

� Monitored active volcano

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FORMS OF VOLCANOES FORMS OF VOLCANOES

Controlled mainly by magma compositionControlled mainly by magma composition

High SiOHigh SiO22 (SILICIC)(SILICIC)Low SiOLow SiO22 (BASALTIC)(BASALTIC)

EXPLOSIVEEXPLOSIVEEFFUSIVEEFFUSIVE

Intermediate SiOIntermediate SiO22

(ANDESITIC)(ANDESITIC)

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GeochemicalGeochemical--Rheological GuideRheological Guide

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��Low, symmetrical accumulations of scoria (cinder)/ ashLow, symmetrical accumulations of scoria (cinder)/ ash

��Typically low SiOTypically low SiO22 (Basaltic) magma(Basaltic) magma

��OneOne--shot volcanoes! Usually related to bigger onesshot volcanoes! Usually related to bigger ones

Volcano Type: MONOGENETIC CONESVolcano Type: MONOGENETIC CONES

(Tuff/cinder cones, tuff rings, maars)(Tuff/cinder cones, tuff rings, maars)

1943 1943

Paricutin Paricutin

eruption, eruption,

MexicoMexico

LigLigññon Hillon Hill

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Volcano Type: MONOGENETIC CONESVolcano Type: MONOGENETIC CONES

(Tuff/cinder cones, tuff rings, maars)(Tuff/cinder cones, tuff rings, maars)

Alligator LakeAlligator Lake

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��MoundMound--shaped or convex volcanoesshaped or convex volcanoes

��Formed by repeated, slow lava extrusion; dome complexesFormed by repeated, slow lava extrusion; dome complexes

��All types of magma (lowAll types of magma (low--high SiOhigh SiO22))

��E.g. HibokE.g. Hibok--Hibok & Vulcan, Camiguin; Mt. Unzen, JapanHibok & Vulcan, Camiguin; Mt. Unzen, Japan

Hibok-Hibok & the 1871 dome Vulcan, Camiguin

Volcano Type: VOLCANIC DOMESVolcano Type: VOLCANIC DOMES

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Volcano Type: VOLCANIC DOMESVolcano Type: VOLCANIC DOMES

��High silica domes are capable of High silica domes are capable of

explosive eruption!explosive eruption!

Unzen VolcanoUnzen Volcano Soufriere Hills, MontserratSoufriere Hills, Montserrat

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�� ConeCone--shaped, with summit crater; may have multiple cratersshaped, with summit crater; may have multiple craters

�� Formed by repeated, alternating deposits of pyroclastics & lava Formed by repeated, alternating deposits of pyroclastics & lava flowflow

�� Intermediate SiOIntermediate SiO22 (Andesitic)(Andesitic)

�� E.g. Mayon, Albay; Matutum, So. Cotabato; Mt. Fuji, JapanE.g. Mayon, Albay; Matutum, So. Cotabato; Mt. Fuji, Japan

Volcano Type: STRATOVOLCANOESVolcano Type: STRATOVOLCANOES

Mayon VolcanoMayon Volcano

Bulusan VolcanoBulusan Volcano

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��GentleGentle--sloped but large diameter volcanoessloped but large diameter volcanoes

��Typically island volcanoes, partially submergedTypically island volcanoes, partially submerged

��Formed by frequent, longFormed by frequent, long--period (can last for years!) lava eruptions in rift period (can last for years!) lava eruptions in rift

zones, mantle hotspotszones, mantle hotspots

��LowLow--high SiOhigh SiO2 2 (basaltic) magma(basaltic) magma

��E.g. Kilauea, Mauna Loa, PuE.g. Kilauea, Mauna Loa, Pu’’u Ou O’’o, Hawaii; Mt. Etna, Italyo, Hawaii; Mt. Etna, Italy

Mauna Loa, the worldMauna Loa, the world’’s s

largest volcanolargest volcano

Volcano Type: SHIELD VOLCANOESVolcano Type: SHIELD VOLCANOES

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��Large; may have several volcanic centers in & around a crater >2Large; may have several volcanic centers in & around a crater >2 km diamkm diam

��Formed by long periods of explosive activity (intermediate lowFormed by long periods of explosive activity (intermediate low--key volcanic key volcanic

activity)activity)

��High SiOHigh SiO22 (Silicic) magma(Silicic) magma

��E.g. Pinatubo; Parker; Krakatau, IndonesiaE.g. Pinatubo; Parker; Krakatau, Indonesia

��Can cause major climate changes, crash of civilizations!Can cause major climate changes, crash of civilizations!

Volcano Type: CalderaVolcano Type: Caldera

Aniakchiak Caldera, AlaskaAniakchiak Caldera, AlaskaPinatubo Caldera, LuzonPinatubo Caldera, Luzon

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Volcano Type: CalderaVolcano Type: Caldera

Crater Lake, OregonCrater Lake, Oregon

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Santorini, Greece: 1500 Santorini, Greece: 1500

B.C. eruption is believed to B.C. eruption is believed to

have caused the death of have caused the death of

the Minoan Civilization in the Minoan Civilization in

the island of Cretethe island of Crete

Type of Volcano: CalderaType of Volcano: Caldera

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STYLES OF VOLCANIC STYLES OF VOLCANIC

ERUPTIONERUPTIONControlled mainly by magma composition (silica content) & Controlled mainly by magma composition (silica content) &

volatile (gas) contentvolatile (gas) content

High SiOHigh SiO22 (SILICIC)(SILICIC)Low SiOLow SiO22 (BASALTIC)(BASALTIC)

EXPLOSIVEEXPLOSIVEEFFUSIVEEFFUSIVE

Intermediate SiOIntermediate SiO22

(ANDESITIC)(ANDESITIC)

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��SteamSteam--driven eruptions caused by contact driven eruptions caused by contact

of groundwater w/ hot country rocks (no of groundwater w/ hot country rocks (no

magma involved)magma involved)

��Usually precursory to magmatic eruptionsUsually precursory to magmatic eruptions

��Short ash columns, ashfallShort ash columns, ashfall

1984 Phreatic 1984 Phreatic

event at Mayon event at Mayon

1976 Phreatic eruption at Taal 1976 Phreatic eruption at Taal

Type of Volcanic Eruption: PHREATIC Type of Volcanic Eruption: PHREATIC

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2000 Phreatic eruption, Mt. Usu2000 Phreatic eruption, Mt. Usu

Type of Volcanic Eruption: PHREATIC Type of Volcanic Eruption: PHREATIC

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1966 Taal Volcano 1966 Taal Volcano

phreatomagmatic phasephreatomagmatic phase

��Very violent eruption Very violent eruption

generated by the explosive generated by the explosive

contact of erupting magma with contact of erupting magma with

waterwater

��Voluminous, slightly tall ash Voluminous, slightly tall ash

columns, laterallycolumns, laterally--projected projected

pyroclastic currents (base pyroclastic currents (base

surges) & blastssurges) & blasts

Type of Eruption:Type of Eruption:

PHREATOMAGMATICPHREATOMAGMATIC

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��Weak to violent eruption of gasWeak to violent eruption of gas--

charged fluid magma characterized by charged fluid magma characterized by

lava fountaining & flowing lava fountaining & flowing

��Lava flowsLava flows

Type of Eruption: HAWAIIANType of Eruption: HAWAIIAN--STROMBOLIANSTROMBOLIAN

Ongoing eruption at Stromboli, ItalyOngoing eruption at Stromboli, Italy

2000 Mayon eruption2000 Mayon eruption

Strombolian phaseStrombolian phase

PHIVOLCS DOST1969 Mt. Tabaro (Taal Volcano) Eruption1969 Mt. Tabaro (Taal Volcano) Eruption

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��CanonCanon--like explosions produced by the detonation of a solidified like explosions produced by the detonation of a solidified

magma plug in the vent by gas accumulated beneath itmagma plug in the vent by gas accumulated beneath it

��Ca. 20 km tall eruption columns; pyroclastic flows, ashfallCa. 20 km tall eruption columns; pyroclastic flows, ashfall

Vulcanian Phase Mayon 2000 eruption

Type of Eruption: VULCANIANType of Eruption: VULCANIAN

1997 1997

Soufriere Soufriere

Hills Hills

Eruption, Eruption,

MontserratMontserrat

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��Very explosive, energetic Very explosive, energetic

release of voluminous release of voluminous

magmatic gas, fragmented magmatic gas, fragmented

magma w/c propel w/ great magma w/c propel w/ great

force high in the air, forming force high in the air, forming

huge mushroom cloudshuge mushroom clouds

��Tall eruption column >40 km Tall eruption column >40 km

high, penetrating stratospherehigh, penetrating stratosphere

��WellWell--defined umbrella clouddefined umbrella cloud

��Extensive ashfallExtensive ashfall

��Pyroclastic flowsPyroclastic flows

��Large volcanic calderasLarge volcanic calderas

Type of Eruption: Type of Eruption:

PLINIANPLINIAN

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VOLCANIC HAZARDSVOLCANIC HAZARDS

VolcanoVolcano--related phenomena/ processes that pose related phenomena/ processes that pose

potential threat or cause negative impact to man, property potential threat or cause negative impact to man, property

& the environment, in a given period of time.& the environment, in a given period of time.

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VOLCANIC HAZARDS

��LAVA FLOWSLAVA FLOWS

��PYROCLASTIC PYROCLASTIC

FLOWS & SURGESFLOWS & SURGES

��ASHFALL OR ASHFALL OR

TEPHRA FALLTEPHRA FALL

��LAHARSLAHARS

��VOLCANIC VOLCANIC

GASESGASES

��FISSURINGFISSURING

��TSUNAMISTSUNAMIS

��DEBRIS AVALANCHE/SECTOR COLLAPSEDEBRIS AVALANCHE/SECTOR COLLAPSE

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��Gravitational settling of Gravitational settling of

volcanic ash & fragments from volcanic ash & fragments from

the umbrella clouds of tall the umbrella clouds of tall

eruption columns & ashclouds eruption columns & ashclouds

of pyroclastic flowsof pyroclastic flows

��Dispersal depends on Dispersal depends on

prevalent wind directions, prevalent wind directions,

column heightscolumn heights

Pinatubo, Philippines, 1991

Volcanic Hazard:Volcanic Hazard:

ASHFALL or ASHFALL or

TEPHRA FALLTEPHRA FALL

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Impacts of AshfallImpacts of Ashfall

��Results to widespread Results to widespread

infrastructural damages infrastructural damages

when thickwhen thick

��Monitored worldwide by Monitored worldwide by

aviation agencies because aviation agencies because

ashfall can cause potential ashfall can cause potential

jet engine failure to all jet engine failure to all

types of aircrafttypes of aircraft

Pinatubo, Philippines, 1991Pinatubo, Philippines, 1991

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Impacts of AshfallImpacts of Ashfall

Buildings destroyed by ballistic mudballs from the 2000 Mt. Usu Eruption

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��Incandescent rivers of hot molten Incandescent rivers of hot molten

rock (lava)rock (lava)

��Erupted from volcanic craters, Erupted from volcanic craters,

fissures, during Hawaiianfissures, during Hawaiian--

Strombolian activity, lava dome Strombolian activity, lava dome

eruptionseruptions

��Usually slowUsually slow--moving for moving for

moderatemoderate--high SiOhigh SiO22 magma; fastmagma; fast--

moving for low SiOmoving for low SiO22 magma (e.g. magma (e.g.

Hawaii lavas)Hawaii lavas)

From USGSFrom USGS

Kilauea lava flowKilauea lava flow

Low Low SiOSiO22 �������� Pahoehoe (Ropy) LavaPahoehoe (Ropy) Lava

Volcanic Hazard:Volcanic Hazard:

LAVA FLOWLAVA FLOW

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1969 Taal Volcano (Mt. Tabaro) Lava Flow Field1969 Taal Volcano (Mt. Tabaro) Lava Flow Field

Low Low SiOSiO22 �������� Aa (Spiky) LavaAa (Spiky) Lava

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1993 Mayon lava flow1993 Mayon lava flow

Intermediate Intermediate SiOSiO22 �������� Blocky LavaBlocky Lava

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1993 Mayon lava flow1993 Mayon lava flow

Intermediate Intermediate SiOSiO22 �������� Blocky LavaBlocky Lava

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Impacts of Lava FlowImpacts of Lava Flow

From USGSFrom USGS

��Main hazard of burial, generation of deadlier pyroclastic flowsMain hazard of burial, generation of deadlier pyroclastic flows

��Results in long term disuse of buried land!Results in long term disuse of buried land!

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��Turbulent mass of ejected Turbulent mass of ejected

fragmented volcanic materials (ash & fragmented volcanic materials (ash &

rocks) + hot gases that flow downslope rocks) + hot gases that flow downslope

at very high speeds (> 60 kph)at very high speeds (> 60 kph)

��Deadliest of all volcanic hazardsDeadliest of all volcanic hazards

Volcanic Hazard:Volcanic Hazard:

PYROCLASTIC FLOWS & SURGESPYROCLASTIC FLOWS & SURGES

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��Collapse and fallback from tall eruption eruption columns (ST. Collapse and fallback from tall eruption eruption columns (ST.

VINCENTVINCENT--TYPE)TYPE)

��Gravitational collapse/ nonGravitational collapse/ non--explosive avalanching of material from explosive avalanching of material from

domes, lava flows (MERAPIdomes, lava flows (MERAPI--TYPE)TYPE)

��Explosions during or after the ascent of lava domes (PLEEANExplosions during or after the ascent of lava domes (PLEEAN--TYPE)TYPE)

��Voluminous silicic magma eruption leading to caldera collapse Voluminous silicic magma eruption leading to caldera collapse

(KRAKATOAN(KRAKATOAN--TYPE)TYPE)

��Voluminous silicic magma eruption from fissure or fault systems Voluminous silicic magma eruption from fissure or fault systems (VTTS(VTTS--

or VALLESor VALLES--TYPE)TYPE)

Origins of pyroclastic flows & surges:Origins of pyroclastic flows & surges:

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��Burning & incineration of everything in the flow pathBurning & incineration of everything in the flow path

��Filling of river valleys w/ pyroclastic flow depositsFilling of river valleys w/ pyroclastic flow deposits

Impacts of Pyroclastic Flows & Surges:Impacts of Pyroclastic Flows & Surges:

RidgeRidge

RidgeRidge

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HibokHibok--hibok Volcano, hibok Volcano,

Camiguin Island, December Camiguin Island, December

1951: 500 deaths from 1951: 500 deaths from

pyroclastic flowspyroclastic flows

Impacts of Pyroclastic Impacts of Pyroclastic

Flows & Surges:Flows & Surges:

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1911 Taal Volcano eruption: 300 deaths from 1911 Taal Volcano eruption: 300 deaths from base surgebase surgess, a type of , a type of

pyroclastic surge that travels laterally outward from the base opyroclastic surge that travels laterally outward from the base of an f an

eruption column at 90eruption column at 90--500 m/s, first recognized in 1947 in explosion 500 m/s, first recognized in 1947 in explosion

mushrooms of underwater nuclear testsmushrooms of underwater nuclear tests

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Volcanic Hazards:Volcanic Hazards:

LAHARSLAHARS

��Rapidly flowing thick mixture of volcanic sediments and waterRapidly flowing thick mixture of volcanic sediments and water

��Triggered by rainfall, melting of craterial icecaps, lake breakoTriggered by rainfall, melting of craterial icecaps, lake breakout or ut or

hydrothermal hydrothermal ““squeezingsqueezing””

1995 Typhoon Mameng Lahars, Bacolor, Pampanga

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•• Debris flow: Debris flow: solid fraction is 60solid fraction is 60--80% by weight or >60% by volume80% by weight or >60% by volume

•• Hyperconcentrated streamflow:Hyperconcentrated streamflow: solid fraction 20solid fraction 20--60% by weight, 4060% by weight, 40--60% 60%

by volumeby volume

Two Classes of LaharsTwo Classes of Lahars

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November 2006 Typhoon Reming Lahar Deposit, Brgy. Maipon, Guinobatan, Albay

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Impacts of LaharsImpacts of Lahars

19911991

19921992DIZON MINESDIZON MINES

COMMUNITYCOMMUNITY

SacobiaSacobia--Bamban RiverBamban River

��BurialBurial

��Cutoff and IsolationCutoff and Isolation

��LongLong--term siltation & term siltation &

related floodingrelated flooding

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Volcanic Hazard: GasesVolcanic Hazard: Gases

��Basic components of magma Basic components of magma

or lava (Hor lava (H22O, COO, CO22, CO, H, CO, H22S, FS, F22, ,

SOSO22, H, H22SOSO44, etc.), etc.)

��Mostly toxic speciesMostly toxic species

From USGSFrom USGS

From USGSFrom USGS

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Bubbling of water during 1969 eruption, Taal Lake, due to Bubbling of water during 1969 eruption, Taal Lake, due to escaping gas from magma beneath the lake floorescaping gas from magma beneath the lake floor

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Volcanic Hazard:Volcanic Hazard: GROUND FISSURINGGROUND FISSURING

��due to movement of magma beneath the surfacedue to movement of magma beneath the surface

��may be movement / adjustments along faultsmay be movement / adjustments along faults

�� accompanied by earthquakesaccompanied by earthquakes

1911 eruption fissure, Lemery, Batangas

PHIVOLCS DOST2000 Mt. Usu eruption fissuring

PHIVOLCS DOST

Volcanic Hazard: DEBRIS AVALANCHEVolcanic Hazard: DEBRIS AVALANCHE

��Downslope movement of largeDownslope movement of large--volume proportions of the volcanic flanks volume proportions of the volcanic flanks

due to:due to:

••movement of magma beneath the edifice (Bezymmianymovement of magma beneath the edifice (Bezymmiany--type)type)

••adjustments along faults transecting volcanoesadjustments along faults transecting volcanoes

••earthquakes (Bandaiearthquakes (Bandai--type)type)

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Volcanic Hazard: DEBRIS AVALANCHEVolcanic Hazard: DEBRIS AVALANCHE

��Produces horseshoeProduces horseshoe--shaped crater, hummocky topographyshaped crater, hummocky topography

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VOLCANIC HAZARDS VOLCANIC HAZARDS

MITIGATIONMITIGATION

We cannot control volcanic phenomenon, but we can We cannot control volcanic phenomenon, but we can

lessen their riskslessen their risks

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Volcano MonitoringVolcano Monitoring

��Indirect measurement of the condition of the magmatic systemIndirect measurement of the condition of the magmatic system

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VolcanoVolcano--Geologic MappingGeologic Mapping��Determine eruption history, eruption Determine eruption history, eruption

recurrencerecurrence

��Determine types and extents of potential Determine types and extents of potential

eruptionseruptions

��Determine eruption behaviorDetermine eruption behavior

PHIVOLCS DOST

Volcanic Hazards ModelingVolcanic Hazards Modeling��Numerically simulate the extents of volcanic flows based on geolNumerically simulate the extents of volcanic flows based on geologic dataogic data

PHIVOLCS DOST

Lahar Hazards Map, Bulusan Lahar Hazards Map, Bulusan

Volcano, based on USGS Volcano, based on USGS

modeling program LAHARZmodeling program LAHARZ

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Information Dissemination & WarningInformation Dissemination & Warning

��Communicate volcano information to government/disaster officialsCommunicate volcano information to government/disaster officials for for

appropriate mitigation strategies & land useappropriate mitigation strategies & land use

��Disseminate volcano information to the public to educate them onDisseminate volcano information to the public to educate them on

appropriate crisis responseappropriate crisis response

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Mitigation of Volcanic Hazards in the Mitigation of Volcanic Hazards in the CommunityCommunity

��Determine which areas (schools, communities) should be Determine which areas (schools, communities) should be

evacuated & avoided during eruptions evacuated & avoided during eruptions

��Determine safe routes & sites for evacuationDetermine safe routes & sites for evacuation

��Plan locations of settlements, schoolsPlan locations of settlements, schools

��Conduct evacuation drillsConduct evacuation drills

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Mitigation of Volcanic Hazards in the Mitigation of Volcanic Hazards in the CommunityCommunity

��Observance of Observance of

PERMANENT PERMANENT

DANGER ZONES DANGER ZONES

(PDZ)(PDZ)

PHIVOLCS DOST

��Educating the community on eruption responseEducating the community on eruption response

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THANK YOU FOR YOUR THANK YOU FOR YOUR ATTENTIONATTENTION☺☺☺☺☺☺☺☺