A link A link betweenbetween LusiLusi and and thethe volcanicvolcanic complexcomplex??………………InsightsInsights from gas from gas geochemistrygeochemistry

AdrianoAdriano MazziniMazzini

Triggering hypothesesTriggering hypotheses

Based on Based on drilling data drilling data interpretation: interpretation: twotwo conflicting conflicting hypotheseshypotheses

a)a) ManMan--mademade

b)b) Not man madeNot man made

Based on Based on field observationsfield observations and and experimental dataexperimental data::

)) id fid f h kh k f lf l i ii i iia)a)Evidence of Evidence of earthquakeearthquake--faultfault reactivation reactivation connectionconnection

Natural trigger option: what is the role of the volcanic Natural trigger option: what is the role of the volcanic gg pgg parc in all thisarc in all this??

The bigger picture: regional observationsThe bigger picture: regional observations

Field observations Field observations and key findings in eastern Java: and key findings in eastern Java:

a)a) Numerous Numerous mud volcanoes mud volcanoes and seeps and seeps Lusi not the Lusi not the only mud eruption siteonly mud eruption site

b)b) Lusi is aligned along a Lusi is aligned along a major fault zone major fault zone External External trigger plausibletrigger plausibletrigger plausibletrigger plausible

c)c) Proximity to the Proximity to the volcanic arc volcanic arc Influence of deep Influence of deep l i t ?l i t ?volcanic system?volcanic system?

Key findingsKey findings: mud volcanism is common: mud volcanism is common

Mud volcanism Mud volcanism is a very is a very common phenomenon in common phenomenon in IndonesiaIndonesia

Gresik

Tuban

IndonesiaIndonesia

The The geological setting geological setting of of Java:Java: text book exampletext book example

OffshoreJava: Java: text book example text book example for mud volcano for mud volcano formationformation

Has there ever been a Has there ever been a Lusi in the past? Lusi in the past? Likely, Likely, based on geological and based on geological and historical datahistorical data

Mazzini Mazzini et al. et al. 20092009

Key findingsKey findings: mud volcanism (?) in the past: mud volcanism (?) in the past

Porong structure located few Porong structure located few kilomets NE of Lusi kilomets NE of Lusi

••Collapse structureCollapse structure

••Presence of an ancient Presence of an ancient piercement structurepiercement structure

••Related to mud volcanism (?)Related to mud volcanism (?)

IstadiIstadi et al. et al. 20092009b-96-504b-96-504

Key findingsKey findings: Lusi along the Watukosek Fault system : Lusi along the Watukosek Fault system

W k kW k k f l hf l h GeologicalGeological featuresfeatures clearlyclearlyWatukosek Watukosek fault hosts fault hosts other mud volcanoes other mud volcanoes on NE on NE JavaJava

GeologicalGeological features features clearlyclearlyindicateindicate thethe presencepresence ofofthethe faultfault ((dasheddashed line)line)

Mazzini Mazzini et al. et al. 20092009

Key findingsKey findings: Watukosek Fault at depth: Watukosek Fault at depth

Seismic profilesSeismic profiles collected collected during 1980’s sistematically during 1980’s sistematically

show the presence of ashow the presence of ashow the presence of a show the presence of a fulted zone fulted zone both on the both on the SWSW

and and NE of Lusi siteNE of Lusi site

Mazzini Mazzini et al. et al. 20092009

Pressure loss at various wells in May 2006Pressure loss at various wells in May 2006

G InterestinglyInterestingly Wunut,Wunut,

Carat field

Wunut field

T l i

Gunung Anyar

Interestingly Interestingly Wunut, Wunut, Carat, Tanggulangin Carat, Tanggulangin gas gas and oil fields and the and oil fields and the water wells close towater wells close toCarat field Tanggulangi

fieldLUSI

water wells close to water wells close to Gunung Anyar Gunung Anyar report report sudden pressure loss after sudden pressure loss after the 27the 27--0505--2006 2006 earthquake. earthquake.

Fluids flushed away Fluids flushed away from aquiferfrom aquifer

Mazzini Mazzini et al. et al. 2009, MPG2009, MPG

Key findingsKey findings: May 2006: several mud and : May 2006: several mud and gas eruptions suddenly appearedgas eruptions suddenly appearedgas eruptions suddenly appearedgas eruptions suddenly appeared

•• FirstFirst eruption eruption 700 m700 m from from drillingdrilling sitesitepp gg•• Sequence of Sequence of eruptionseruptions orientedoriented along a > 1000 m along a > 1000 m SWSW--NENE trendtrend

Mazzini Mazzini et al. et al. 20072007

Key findingsKey findings: aligned eruption sites: aligned eruption sites

3

4

4'

EruptionsEruptions followfollowthethe WatukosekWatukosekfaultfault directiondirection((numbersnumbers referrefer toto

5

((numbersnumbers referrefer to to previousprevious image, image,

listedlisted in in chronologicalchronological

sequencesequence))

NE

sequencesequence))

Mazzini Mazzini et al. et al. 2007, EPSL2007, EPSL

Key findingsKey findings: LUSI prograding cracks after EQ: LUSI prograding cracks after EQ

Fractures Fractures follow thefollow thefollow the follow the Watukosek Watukosek

fault directionfault direction

Key findingsKey findings: LUSI prograding cracks after EQ: LUSI prograding cracks after EQ

N

N

Prograding cracks observed throughPrograding cracks observed throughN Prograding cracks observed through Prograding cracks observed through the village after EQ. the village after EQ. follow the follow the Watukosek fault directionWatukosek fault direction

N

Key findingsKey findings: faulting north of LUSI: faulting north of LUSI

N N

FaultingFaulting follows the Watukosek fault directionfollows the Watukosek fault direction

Mazzini Mazzini et al. et al. 20092009

Key findingsKey findings: Collapse/new seeps follow fault trend: Collapse/new seeps follow fault trend

Subsidence monitoring Subsidence monitoring October_augustOctober_august 20062006IstadiIstadietet al. al. 20092009

Key findingsKey findings: seismics show pre: seismics show pre--existing piercementexisting piercement

i ii i filfil f ’f ’SeismicSeismic profilesprofiles from 1980’s from 1980’s show show presencepresence ofof growinggrowing

piercement piercement structurestructure at Lusi at Lusi ppsitesite..

TypicalTypical ofof gelogicalgelogical featuresfeaturesTypicalTypical ofof gelogicalgelogical features features thatthat willwill manifest manifest to to thethe

surfacesurface

Lusi Lusi wouldwould have have eruptederuptedsoonersooner or lateror later

Mazzini Mazzini et al. et al. 20072007

Key findingsKey findings: : OriginOrigin ofof eruptederupted solid/fluids solid/fluids ((basedbased onon observationsobservations mademade in 2006)in 2006)

KeypointsKeypoints0

SOLID

GAS

•• The LUSI system formed in a geological The LUSI system formed in a geological setting setting proneprone to mud volcanismto mud volcanism

500

GAS

WATER

proneprone to mud volcanism to mud volcanism

••Main Main gasgas COCO22+CH+CH44+acqueous vapour+acqueous vapour

epth

(m)

1000

•• IllitizationIllitization throughout clayey unitthroughout clayey unit

•• Main source forMain source for waterwater--gasgas--mud 1100mud 1100--1850 m1850 m

De

1500

•• Main source for Main source for waterwater gasgas mud 1100mud 1100 1850 m1850 mLarge amount of water availableLarge amount of water available

•• PossiblePossible deeper sourcedeeper source of water/gas NOTof water/gas NOT

2000

•• Possible Possible deeper source deeper source of water/gas NOT of water/gas NOT obvious from sample analyses.obvious from sample analyses.2500

Deeper

??

Deeper

??Mazzini Mazzini et al. et al. 20072007

What is Lusi?What is Lusi?MUD VOLCANISM MUD VOLCANISM

“Geological phenomena made manifest through the sudden “Geological phenomena made manifest through the sudden eruption or quiescent extrusion of sediment, rock, and fluids eruption or quiescent extrusion of sediment, rock, and fluids from deeper strata of an from deeper strata of an hydrocarbon bearing basinhydrocarbon bearing basin””

ReservoirOther fluids

Source rock

Reservoir

Mazzini Mazzini et al. et al. 20092009

Is Lusi really a mud volcano?Is Lusi really a mud volcano?•• TYPICALTYPICAL FOR MUD VOLCANO FOR MUD VOLCANO •• SettingSetting

M h lM h l•• MorphologyMorphology•• Presence of mud brecciPresence of mud brecciaa•• Water from illitization of clay mineralsWater from illitization of clay minerals•• Water from illitization of clay mineralsWater from illitization of clay minerals

•• ATYPICALATYPICAL FOR MUD VOLCANOFOR MUD VOLCANO•• High geothermal gradient (shallow geochemical High geothermal gradient (shallow geochemical

reactions)reactions)•• Longlasting eruptionLonglasting eruption•• Pulsating behavious (geyserPulsating behavious (geyser--like?)like?)

COCO dominated gasdominated gas•• COCO22--dominated gasdominated gas

Sampling 2006Sampling 2006--2010 2010 (34 samples)(34 samples)

Group 1: Group 1: HOTHOT fluids from fluids from mainmain cratercrater ((COCO22--dominated)dominated)

Wunut Lusi Sim

ila

Group 2: Group 2: COLDCOLD fluids from fluids from satellitesatellite seepsseeps (CH(CH44 --dominateddominated))

ar isot. comdominateddominated))

Group 3: Group 3: fluids from fluids from WunutWunutgas gas fieldfield

mp

gg

Group 4: Group 4: Fluids from Fluids from MVsMVs in in easteast JavaJava

Methane zonation diagramsMethane zonation diagrams

Diagrams Diagrams indicateindicate thatthat

••Lusi 2006Lusi 2006: : thethe earlyearly sampling sampling mademade in 2006 shows in 2006 shows contributionscontributions ofof microbialmicrobial CHCH44 componentcomponent ((KaliberhKaliberh Fm. Fm.

ll i l)ll i l)+ alluvial)+ alluvial)

••LusiLusi afterafter 20062006: thermogenic: thermogenic signaturesignatureLusi Lusi afterafter 20062006: thermogenic : thermogenic signaturesignature

••WunutWunut: thermogenic : thermogenic signaturesignature ((althoughalthough veryvery shallowshallow))

••OtherOther MVsMVs in in easteast JavaJava: : mixedmixed gas gas

Hydrocarbons maturity plotsHydrocarbons maturity plots

MaturityMaturity plotsplots indicateindicate aa deepdeep originorigin ofof Lusi gasLusi gas•• MaturityMaturity plots plots indicateindicate a a deepdeep originorigin ofof Lusi gas.Lusi gas.

•• Lusi Lusi plumbingplumbing system system is is muchmuch deeperdeeper thanthanpreviouslypreviously expectedexpected

•• LusiLusi gasgas waswas generatedgenerated atat highhigh temperaturestemperaturesLusi Lusi gasgas waswas generatedgenerated at at highhigh temperaturestemperatures

•• WunutWunut gas is more gas is more fractionatedfractionated comparedcompared to Lusito Lusi

COCO22 and helium and helium originorigin

•• COCO22 gas gas isotopicisotopic compositioncomposition indicatesindicates thatthat highhightemperaturetemperature reactionsreactions generatedgenerated thethe eruptederupted gasgas

•• Helium Helium isotopicisotopic valuesvalues and COand CO22/CH/CH44 alsoalso indicateindicatehighhigh equilibriumequilibrium temperaturestemperatures as as wellwell as as presencepresenceofof mantlemantle originorigin fluidsfluidsofof mantle mantle originorigin fluidsfluids

•• Hot fluids Hot fluids areare involvedinvolved in in thethe ongoingongoingh i lh i l iigeochemicalgeochemical reactionsreactions

AnAn intrusionintrusion and/orand/or hot fluidshot fluids formform thethe neighbouringneighbouring

A new scenario for the lusi eruptionA new scenario for the lusi eruptionAn An intrusionintrusion and/or and/or hot fluids hot fluids form form thethe neighbouringneighbouring

ArjunoArjuno--Welirang Welirang volcanicvolcanic complexcomplex explainsexplains thetheobservationsobservations indicatingindicating thatthat it is it is responsibleresponsible for:for:

•• HighHigh geothermalgeothermal gradientgradient•• SignificantSignificant COCO22 productionproductionSignificantSignificant COCO22 productionproduction•• HighHigh temperaturetemperature generationgeneration ofof COCO22 and CHand CH44

•• PresencePresence ofof mantle gasmantle gas

The intrusion scenarioThe intrusion scenarioPossible intrusion from the neighbouring volcanic Possible intrusion from the neighbouring volcanic

complex already suggested in 1999complex already suggested in 1999

Kusumastuti Kusumastuti et al. 1999et al. 1999

The ArjunoThe Arjuno--Welirang volcanic complexWelirang volcanic complex

•• GrowthGrowth ofof thethe complexcomplexevolvingevolving towardstowards thethe NENE

•• WatukosekWatukosek faultfaultsystemsystem followsfollows thethe samesamesystem system followsfollows thethe same same NE NE directiondirection hosting hosting otherother mud mud volcanoesvolcanoes

•• EvidenceEvidence ofof hot fluids hot fluids interactioninteraction alongalong thetheescarpmentescarpment

Seismicity?Seismicity?Is the frequent seismicity affecting the system:Is the frequent seismicity affecting the system:

Lusi Lusi

FaultFault

Volcanic system?Volcanic system?Volcanic system?Volcanic system?

Increased activity of other mud volcanoes along Increased activity of other mud volcanoes along fault after May 2006 earthquakefault after May 2006 earthquake

Coincidentially Coincidentially other mud other mud volcanoesvolcanoes along Watukosek along Watukosek fa lt e efa lt e e mo e acti e aftemo e acti e afte

y qy q

fault were fault were more active after more active after earthquakeearthquake when activity when activity

started around Lusi.started around Lusi.

SemeruSemeru + + MerapiMerapi stronger stronger activity after earth quakeactivity after earth quake

Earthquake and loss of circulation at Earthquake and loss of circulation at drilling sitedrilling sitedrilling sitedrilling site

Coincidently Coincidently partial loss partial loss of circulation of circulation after the earthquakeafter the earthquakeand and

total loss total loss of circulation of circulation followingfollowing the two the two after shocksafter shocks

SawoloSawolo et al. et al. 20092009

Lusi Lusi responseresponse afterafter earthquakesearthquakes

•• SinceSince 2006, in 2006, in numerousnumerousinstancesinstances Lusi Lusi appearedappeared to to respondrespond to to seismicseismic activityactivity((seesee MazziniMazzini et al.et al. 2007, 2007, 2009)2009)2009)2009)

•• RecentRecent seismicseismic activityactivity(i e 2011)(i e 2011) alsoalso revealedrevealed(i.e. 2011) (i.e. 2011) alsoalso revealedrevealedprompt prompt responseresponse ofof Lusi Lusi behaviourbehaviour

Mazzini Mazzini et al. et al. 2009, MPG2009, MPG

Predictions about Lusi longevityPredictions about Lusi longevity•• Combined effect of:Combined effect of:

–– SeismicitySeismicity–– Alterations of magmatic chamberAlterations of magmatic chamber–– Reactivation of Watukosek faultReactivation of Watukosek fault

–– Effect on rheology of sediments and Effect on rheology of sediments and gygycritical overpressurecritical overpressure

SummarySummary

Lusi is part of a larger Lusi is part of a larger sedimentsediment--hosted hydrothermal hosted hydrothermal tt t d t th A jt d t th A j W li l iW li l isystem system connected to the Arjunoconnected to the Arjuno--Welirang volcanic Welirang volcanic

complexcomplex

A deeper sited magmatic A deeper sited magmatic intrusionintrusion or migration of or migration of hot hot fluidsfluids explains the geochemical signature observedexplains the geochemical signature observed

Lusi cannot be a representative example of a mud Lusi cannot be a representative example of a mud volcanovolcano

terima kasihterima kasih

ReferencesReferences

• Istadi, B.P., Pramono, G.H., Sumintadireja, P. and Alam, S., 2009. Modeling study of growth d i l h d f LUSI d l E J I d i M i d P land potential geohazard for LUSI mud volcano: East Java, Indonesia. Marine and Petroleum 

Geology, 26(9): 1724‐1739.

• Mazzini, A., 2009. Mud volcanism: Processes and implications. Marine and Petroleum Geology, 26(9): 1677‐1680.

• Mazzini, A., Nermoen, A., Krotkiewski, M., Podladchikov, Y., Planke, S. and Svensen, H., 2009. Strike‐slip faulting as a trigger mechanism for overpressure release through piercement structures. Implications for the Lusi mud volcano, Indonesia. Marine and Petroleum Geology, 26(9): 1751‐1765.( )

• Mazzini, A., Svensen, H., Akhmanov, G.G., Aloisi, G., Planke, S., Malthe‐Sorenssen, A. and Istadi, B., 2007. Triggering and dynamic evolution of the LUSI mud volcano, Indonesia. Earth and Planetary Science Letters, 261(3‐4): 375‐388.