TRAP SIZE DISTRIBUTIONS (4‐WAY DIP CLOSURES ONLY)
TRAPSIZEDISTRIBUTIONS(4‐WAYDIPCLOSURESONLY)
NOVASCOTIAOFFSHORETRAPVOLUMES
Thetotalbasinresourcepoten1alfortheNovaSco1aOffshorewascalculatedusingBEICIP’s3DpetroleumsystemsmodelThemis3D.Themodelwasconstructedusingoutputfromthe3DfaciesmodelDionisos.
Fivesourcerockhorizonsweremodeledusingtheparameterslistedinthetableoverleaf.
Themismodelsthetotalvolumeofhydrocarbonexpelledfromthesesourcerocksis980BnBoe.
Themiscalculatesthevolumeofresourcetrappedinthebasinbycompu1ngthevolumeofdipclosedfeaturesforeachreservoirplayfairway.Inthemodeltherearefiveplayfairways:
1. Ap1an‐Cenomanian2. Hauterivian‐Barremium
3. Barriasian‐Hauterivian4. Oxfordian‐Tithonian5. EarlytoMidJurassic
Theinplacereservesarethecomputedbyfillingthedipclosedfeatureswithmodelednettogrossandporosityderivedfromthe3D faciesmodel. The 2D 1me slices from thismodelwas used as the Gross Deposi1onal Environmentmaps onwhich theCommonRiskSegmentMappingwasdone.IntheCRSexercisetheGDEmapswerehandmodifiedtoensuretheyweregeologicalreasonable.NotethattheserevisedGDE’swerenotthenincorporatedbackintoThemis.
SourceRockparameters
Approx.Age
IniNalTOC KerogentypeandiniNalIH DescripNon
APTIAN 122Ma 2%(constant)
III(con1nental)IH=235mgHC/gTOC
(Dogger.NorthSea)‐Opensystemkine1cs‐Vandenbrouke
etal.1999
Poten1alsourcerockintheNaskapishale,iden1fiedinsomewells.
Variableeffec1vethicknessbetween0–100m.
VALANGINIAN 136Ma 1%(constant)
III(con1nental)IH=235mgHC/gTOC
(Dogger.NorthSea)‐Opensystemkine1cs‐Vandenbrouke
etal.1999
Verypoorandscaaeredsourcerock(coalfragmentsindeltaicenvironment,throughtheMississauga
forma1on)Variableeffec1vethicknessbetween0–200m.
TITHONIAN 148Ma 3%(constant)II‐IIImix
IH=424mgHC/gTOCBestdefinedSR,widelyproven.
Variableeffec1vethicknessbetween0–50m.
CALLOVIAN 160Ma 2%(constant)II‐IIImix
IH=424mgHC/gTOCUncertainextentandrichnessduetothelackofdata.
Variableeffec1vethicknessbetween0–20m.
PLIENSBACHIAN(L.M.Jurassic)
196Ma 5%(constant)
II(marine)IH=600mgHC/gTOC
(Toarcian.France)‐Opensystemkine1cs‐Beharetal.1997
Suspected,notproven.Poten1allypresentabovesaltbasinsonly.
Assumedaveragethickness20m.
NOVASCOTIAOFFSHORETRAPVOLUMES
Theporositywasderivedfromtheburialhistoryandmodifiedfortheeffectsofoverpressure.
Usingthisapproachthevolumeofresourceanditsarealdistribu1onintherespec1vezonesisdependentonthefollowing:
1. Dipclosedvolumes2. Modelledreservoirdistribu1on,nettogrossandporosity.
Themisassumesthatsaltdoesnotseal.Thereforenosaltclosedfeaturesareincludedinthevolumetrics.Wehaveaaachedastructuralmapinthesaltdiapirprovince.Thisshowsalargenumberofthepoten1alclosuresthatarepiercedwithsaltdiapirsandthereforenotincludedinthebasinresourcecalcula1on.Wethereforeassertthatthebasinresourcepoten1alinanyareawheretherearesaltorfaultclosedfeatureswillbeunderes1mated.
Similarly with respect to reservoir distribu1on, the model assumes a ‘blanket reservoir’ with a smooth distribu1on of net to gross andporosity. We know that this is not the case, par1cularly in the deeperwater areas inwhichwe expectmore channelised and fan typereservoirs.Thereforethearealdistribu1onofthebasinresourcees1mateswillbeflawedindeepwater.
Aaachedthereare7figureswhichwesuggestgiveabeaerimpressionofstructuralstyleandscaleofdipclosedfeatures.
ThefirsttwofiguresareextractsfromthestructuralmapattopHauterivian,thesealingsurfacefortheMiddleMississaugareservoir. OnefigureshowsalargedipclosedfeatureintheareaoftheTantallonwell. Wewouldexpectthisfeaturetobecrossedbychannelsandsshedfromtheshelfedge. ThesecondmapshowsthestructuralstyleintheareaoftheShelbourneandTorbrukwells–anareaofintensesaltdiapirism.No1cethenumberoffeaturesclosedagainstsalt.NotethatthefullstructuralmapisinthePFAAlas.
FollowingthetwomapstherearefivehistogramsshowingtheBulkRockVolumesofallthedipclosedfeaturesoneachofthefivereservoirs.Theyareselfexplanatory.Wehavealsoincludedthefinalbasinresourcehistogramsforcomparison.
Tantallon
HauterivianMFSdepthmap
Shelburne
Albatross
Mohican Shuben
HauterivianMFSdepthmap
ApNan‐CenomanianBRV(Mm3)
0.0
200.0
400.0
600.0
800.0
1000.0
1200.0
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85 88 91 94 97100103106109112
Simple4waydipclosuresonly
Hauterivian‐BarremianBRV(Mm3)
0.0
2000.0
4000.0
6000.0
8000.0
10000.0
12000.0
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85 88 91 94 97100103106109112115118
Simple4waydipclosuresonly
Berriasian‐HauterivianBRV(Mm3)
0
200
400
600
800
1000
1200
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85 88 91 94 97100103106109112115118121124
Simple4waydipclosuresonly
Oxfordian‐TithonianBRV(Mm3)
0.0
200.0
400.0
600.0
800.0
1000.0
1200.0
1 2 3 4 5 6 7 8 910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364
Simple4waydipclosuresonly
Early‐MiddleJurassicBRV(Mm3)
0
50
100
150
200
250
300
350
400
1 3 5 7 9 111315171921232527293133353739414345474951535557596163656769717375777981838587899193
Simple4waydipclosuresonly
Zonesforvolumesanalysis
Rankingofthedifferentzones
Zone3‐1/3discovered
mmbbls)
Oilvolumeinm
mbb
ls(surfacecon
diNon
s)