Top Banner
Hydrogeology of a shallow Hydrogeology of a shallow coalbed methane play: A case coalbed methane play: A case study of Ardley coal in west study of Ardley coal in west - - central, Alberta central, Alberta S.M. Harrison, M.Sc., P.Geol., P.Geo. SH Consulting Services In association with NLR Associates Inc.
37

Hydrogeology of a shallow coalbed methane play: A case ... · Hydrogeology of a shallow coalbed methane play: A case . study of Ardley coal in west-central, Alberta. ... Gamma Ray

May 14, 2020

Download

Documents

Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
  • Hydrogeology of a shallow Hydrogeology of a shallow coalbed methane play: A case coalbed methane play: A case study of Ardley coal in weststudy of Ardley coal in west--

    central, Albertacentral, Alberta

    S.M. Harrison, M.Sc., P.Geol., P.Geo.

    SH Consulting Services

    In association with NLR Associates Inc.

  • OutlineOutline

    PART I PART I –– Overview and Well DataOverview and Well Data

    LocationLocationStratigraphy / HydrostratigraphyStratigraphy / HydrostratigraphyWell Drilling / Completion / Well Drilling / Completion / TestingTestingDataData

    PressurePressure““TransmissivityTransmissivity””(permeability)(permeability)Water ChemistryWater Chemistry

    PART II PART II –– Production / Production / Development / RegulatoryDevelopment / RegulatoryTesting Testing –– implications for well implications for well spacingspacingLocal Water Well UseLocal Water Well UseQuantity / Quality Produced Quantity / Quality Produced WaterWater

    PART III PART III -- Regional ConsiderationsRegional ConsiderationsRegional PressureRegional PressureRegional ChemistryRegional ChemistrySynthesisSynthesisOtherOther

  • Study LocationStudy Location

  • Stratigraphic / Hydrostratigraphic Chart

  • Schematic CrossSchematic Cross--sectionsection

    Distribution of coal Distribution of coal –– Plains Area Plains Area (section view; modified AGS(section view; modified AGS--EUB)EUB)

    Schematic Cross-sectioncentral Alberta

    Horizontal Scale (km) A to B

    Vertical Exag. A to B = 25

    Precamb

    rian

    Paleozoi

    c

    Mannville

    Lea Park &

    Colorado

    Wapiti

    Scollard Hor

    seshoe

    Canyon B

    elly

    River

    Paskapoo

    Disturbed Belt

    Edmonton

    X

    X

    Cadomin

    Brazeau

    Coalspur

    A B C

    A

    2000

    1000

    -1000

    -2000

    0 030 90

    0

    C

    B

    B to C

    B to C x 75

  • Data Data –– Coal Testholes Coal Testholes (red)(red)

    High number High number of testholesof testholesData used for Data used for various various mapping mapping themes (e.g. themes (e.g. structure structure contour map contour map showing the showing the distribution of distribution of Ardley coalArdley coal

  • Data Data –– Hydrochemistry Hydrochemistry (DST)(DST)

    Some DSTSome DST’’s s show show ““aa--typicaltypical””water chemistry. water chemistry. e.g. Anomalous e.g. Anomalous DIC (bicarbonate DIC (bicarbonate or HCOor HCO33) ) western part of western part of areaareaIndicator of Indicator of biogenic gas??biogenic gas??Associated Associated sulphate (200 sulphate (200 mg/L)mg/L)Higher gas Higher gas content in parts content in parts of study areaof study area

    8-10-047-04 W5M

  • TargetTarget25

    50

    75

    100

    125

    150

    Coal Zoneapprox. 9 m thick

    Paskapoo Fm (lower)

    Scollard Fm (Ardley Coal Zone)

    Gamma Ray 8-10-47-4 W5M KB = 859 m asl

    Gamma Ray

    Caliper

    Photoelectric Effect

    Density Correction

    Bulk Densitykg/m3

    kg/m3

    API

    API

    150

    150

    0

    0 1900

    450 -50

    2900

    0.0 10.0

    175

    200

    225

    250

    275

    Gamma Ray

    8-10-47-4 W5M KB = 859 m asl

    Gamma Ray

    Photoelectric E ffect

    Density Correction

    Bulk Densitykg/m3

    kg/m3

    API

    API

    150

    150

    0

    0 1900

    450 -50

    2900

    0.0 10.0

    200Paskapoo Fm

    Scollard Fm

    Coal Zone

  • Well Data Well Data –– what we wanted to what we wanted to evaluate and whyevaluate and why

    What:What:PressurePressurePermeabilityPermeabilityWater Chemistry / Water QualityWater Chemistry / Water Quality

    Why: Why: Wet or dry coalWet or dry coalBiogenic gas presentBiogenic gas present““ProducibilityProducibility””Regulatory Regulatory

  • Well 103 Well 103 –– Field MethodsField Methods

    Drilling / CompletionDrilling / Completion

    Testing / Data Collection Testing / Data Collection

  • Field Methods: Field Methods: DrillingDrilling

    Surface casing setSurface casing setAir/mudAir/mud--drilled to targetdrilled to targetIntermediate casing Intermediate casing cemented at the top of cemented at the top of coal target isolating coalcoal target isolating coalCoal air drilled and Coal air drilled and reamedreamedLiner setLiner setNo well stimulationNo well stimulationWell purged of fluid and Well purged of fluid and allowed to equilibrate allowed to equilibrate for 80 hoursfor 80 hours

  • Field Methods: Field Methods: Well SetWell Set--up and Testingup and Testing

    Well 103 and Well 103 and obs. wellobs. wellDownholeDownholesondessondesPump rate in Pump rate in 103 = 26 103 = 26 mm33/day/day@120 minutes @120 minutes pump gas locks pump gas locks (i.e. end of (i.e. end of ““pumppump--off off ““test)test)““BuildBuild--upup””periodperiod

  • Well Data: Pressure BuildWell Data: Pressure Build--up Dataup Data

    BuildBuild--up up period approx. period approx. 3500 minutes3500 minutesStatic pressure Static pressure head 1470 head 1470 kPakPa(150 m or 50 (150 m or 50 m m btopbtop))

    Gas Lock @ 120 min(125 m of drawdown)

  • Well Data: PermeabilityWell Data: Permeability

    CooperCooper--Jacob Jacob SemiSemi--log method log method or or TheisTheisrecoveryrecoveryLate time data Late time data where water where water phase is assumed phase is assumed dominantdominantDefinitely Definitely permeability

  • Well DataWell DataWater Chemistry/QualityWater Chemistry/Quality

    Routine:Routine:NaNa--HCOHCO33 type water, type water, TDS = 1920 mg/LTDS = 1920 mg/LNa = 836 mg/LNa = 836 mg/LClCl = 250 mg/L= 250 mg/LSOSO44 =

  • Isotope GeochemistryIsotope Geochemistry(water and dissolved gas)(water and dissolved gas)

    Isotopes:Isotopes:δδ1313CCDICDIC →→ enriched +22 enriched +22 ‰‰δδ1313CCCH4CH4 →→ depleted depleted --46 to 46 to --51 51 ‰‰δδ1818O/O/δδ22H H →→ meteoricmeteoric33HH →→ nonnon--tritiatedtritiated (test(test--well)well)δδ22HHCH4CH4//δδ22HHH2O H2O →→ suggest COsuggest CO22 reduction pathwayreduction pathway

  • Part I: Summary and ConclusionsPart I: Summary and Conclusions

    Detailed compilation of well data pertaining specifically Detailed compilation of well data pertaining specifically to the ACZ (part) hydraulic regime:to the ACZ (part) hydraulic regime:

    Chemistry Chemistry –– fresh water

  • Part II Part II Production / Development and Production / Development and

    RegulatoryRegulatory

    Data are important to evaluate reservoir character/flow Data are important to evaluate reservoir character/flow system as it pertains to, for example, development / system as it pertains to, for example, development / production (e.g. quantity/quality of water, well spacing, production (e.g. quantity/quality of water, well spacing, etc.); COetc.); CO22 sequestrationsequestration

    Relationship to water wells within the area??Relationship to water wells within the area??

    Code of Practice vs. Code of Practice vs. Water ActWater Act

  • Results Review:Results Review:

    DownholeDownholesondessondesPump rate in Pump rate in 103 = 26 103 = 26 mm33/day/day@120 minutes @120 minutes pump gas locks pump gas locks (i.e. end of (i.e. end of test)test)No No ““interference interference effect effect ””

    100 m

    Recall permeability is relatively low (to water)must “move” water (i.e. depressurize) to attain gas flow

  • Production / Production / DevelopmentDevelopment

    Well Array:Well Array:

    Yellow circle Yellow circle = 800 m = 800 m radiusradius

    Blue =Blue = water wellswater wells

    Red =Red = prodnprodn wellwell(vertical)(vertical)

  • ••Water Act Water Act may be may be applicableapplicable

    CBM Working Group / CBM Working Group / Alberta EnvironmentAlberta EnvironmentEUB: EUB:

    1. Code of Practice1. Code of Practice2. Div. Approval2. Div. Approval3. No Reporting Required3. No Reporting Required

  • Water Well Water Well DistnDistn. .

    Blue =Blue = water wellswater wells

    Within a 600 m Within a 600 m radius testradius test

    Yellow circle Yellow circle –– 800 m radius800 m radius

    TestTest--wellwell

  • Pressure vs. DepthPressure vs. Depth(Test(Test--well 103)well 103)

    0

    50

    100

    150

    200

    2500 500 1000 1500 2000 2500

    Pressure (kPa)

    Dep

    th (m

    )

    Paskapoo/DriftHydrostatic gradientWell 103

    Linear (Hydrostatic gradient)

    Data Gap

  • s

    20

    40

    60

    80

    80

    60

    40

    20

    3

    3HC

    O

    4SO

    + C

    l4

    8020 40 60

    Na + K

    COMg

    SO

    Ca + M

    g

    C a C l

    2 0

    4 0

    6 0

    8 0

    2 0

    4 0

    6 0

    8 0

    80 60 40 20

    80

    60

    40

    20 20

    40

    60

    80

    S3

    S3

    S3

    observation well

    Paskapoo / Drift

    fresh-water

    sea water

    97 6

    10

    3

    45

    8

    1

    11 2

    Piper Plot Piper Plot (water wells and 103)(water wells and 103)

  • Part III: Regional ConsiderationsPart III: Regional Considerations

    Regional PressureRegional PressurePressure vs. DepthPressure vs. DepthHydraulic Head vs. Hydraulic Head vs. ElevationElevationHydraulic Head vs. Hydraulic Head vs. TopoTopoCrossCross--sectionsection

    Regional ChemistryRegional ChemistryPiperPiperδδ1818O vs. O vs. δδ22HHδδ22HHH2OH2O vs. vs. δδ22HHCH4CH4

    SynthesisSynthesisSummary and Summary and interpretation of datainterpretation of data

    FrameworkFrameworkFlowFlowData RequirementsData Requirements

  • Pressure / Hydraulic HeadPressure / Hydraulic Headlowermost lowermost PaskapooPaskapoo -- ArdleyArdley -- ScollardScollard

    Hydraulic Hydraulic Head Head distributiondistributionCrossCross--section linesection lineBB--BB’’

  • TopoTopo vs. Hydraulic Headvs. Hydraulic Head

    correlation with correlation with topography topography ––possibly reflecting possibly reflecting gravity or gravity or topotopodriven flowdriven flow

    Topography (KB elevation) vs. Hydraulic Head

    y = 0.457x + 401.5R2 = 0.5912

    0

    200

    400

    600

    800

    1000

    1200

    0 200 400 600 800 1000 1200 1400

    Topography (m asl)

    Hyd

    raul

    ic H

    ead

    (m

    Group 1

    Group 2

    Linear (Group 1)

    103

  • HydrostratigraphicHydrostratigraphic Section BSection B--BB’’

    CrossCross--section illustrating relative head differences in lowermost section illustrating relative head differences in lowermost PaskapooPaskapoo –– ArdleyArdley –– ScollardScollard (Groups 1 and 2); break in (Groups 1 and 2); break in hydraulic regime shown as dashed linehydraulic regime shown as dashed line

    Section B-B'

    0

    200

    400

    600

    800

    1000

    1200

    -0.25 0.25 0.75 1.25 1.75 2.25 2.75

    Distance (relative)

    Elev

    atio

    n (m

    asl

    )

    TopographyTest Interval Group 1Hydraulic Head Group 1Test Interal Group 2Hydraulic Head Group 2

    Well 103

  • Chemistry Piper DiagramChemistry Piper Diagramlowermost lowermost PaskapooPaskapoo -- ArdleyArdley -- ScollardScollard

    Well 103 is NaWell 103 is Na--HCOHCO33 type type waterwaterObsObs well shown well shown for comparison for comparison (reflects higher (reflects higher sulphatesulphate))Water wells are Water wells are CaCa--Mg HCOMg HCO33typetype

  • δδ1818O O vsvs δδ22HHregionalregional

    WaterWater--line (solid) line (solid) for Edmonton for Edmonton Station with Station with GMWL (dashed) GMWL (dashed)

    Well 103 plots Well 103 plots along line along line suggesting meteoric suggesting meteoric originorigin

  • CO2 Reduction

    -400-350-300-250-200-150-100-50

    0

    -200 -150 -100 -50 0

    Coleman et al. 1988 Aravena et al. 1995 Aravena et al. 2003 Aravena et al. 2003This Study S3 Martini et al. 2003

    δ2Η H2O (‰) VSMOW

    δ2H

    CH

    4 (‰

    ) VSM

    OW

    CO2 reduction trend lineδ2 Η CΗ4 = δ2 Η H2O - 160 +/- 10‰

    δδ22HHH2OH2O vs. vs. δδ22HHCH4CH4

    COCO22 reduction reduction appears to be appears to be the the methanogenicmethanogenicpathwaypathwayContribution Contribution of biogenic of biogenic gasgas

  • SYNTHESISSYNTHESISCrossCross--section Bsection B--BB’’

    Hydraulic Hydraulic head head distributiondistributionCrossCross--section line section line BB--BB’’

  • SynthesisSynthesis

    Recharging meteoric waters represented by Group 1 (Recharging meteoric waters represented by Group 1 (““PaskapooPaskapoo Water SystemWater System””) ) Regional flow system with local flow components normal or nearRegional flow system with local flow components normal or near--normal pressurenormal pressureBiogenic gas (Biogenic gas (methanogenesismethanogenesis) generation within carbon) generation within carbon--rich rich faciesfacies (coal) leading to (coal) leading to high DIC (i.e. high HCOhigh DIC (i.e. high HCO33 concentrations enriched in concentrations enriched in 1313C)C)GasGas--prone lower system?? prone lower system?? -- significantly significantly underpressuredunderpressured

    Section B-B'

    0

    200

    400

    600

    800

    1000

    1200

    -0.25 0.25 0.75 1.25 1.75 2.25 2.75

    Distance (relative)

    Elev

    atio

    n (m

    asl

    )

    TopographyTest Interval Group 1Hydraulic Head Group 1Test Interal Group 2Hydraulic Head Group 2

    Well 103

    Underpressured?Gas Prone?

    18O/2Hmeteoric

    CO2 reduction

  • well 103

    511.37 497.9

    520.5 568

    660m asl

    NESW

    Paskapoo

    Scollard

    Scollard

    ACZ

    Paskapoo

    DisturbedBelt Subcrop

    08-10-47-04

    00/11-01-044-08

    02/11-33-046-06

    local flow line

    regional flow line

    00/12-33-046-06

    00/05-30-042-09

    Gas Prone? Gas Prone?

    FlowFlow

    Impact??

    Impact??18O/2Hmeteoric

    18O/2Hmeteoric

    Flow details??Flow details??

    Local vs. intermediate vs. regionalLocal vs. intermediate vs. regionalAdditional dataAdditional data

  • Detailed View of theCoal Zone

    200

    coalzone

    Well Log (Detailed View)Well Log (Detailed View)

    Scollard?

    Haynes Member(?)

    H = 805 mTDS = 1920mg/LGas/WaterPerm = 1mDIsotopes (2H, 18O, 13C)

  • Summary and ConclusionsSummary and Conclusions

    Detailed compilation of well data pertaining specifically to theDetailed compilation of well data pertaining specifically to theACZ (part) hydraulic regime:ACZ (part) hydraulic regime:

    Chemistry Chemistry –– NaNa--HCOHCO33 type watertype waterPressure Pressure –– near normal pressurenear normal pressurePermeability Permeability –– low likely

  • Thank youThank you

    Hydrogeology of a shallow coalbed methane play: A case study of Ardley coal in west-central, AlbertaOutline�Study LocationSchematic Cross-sectionData – Coal Testholes (red)Data – Hydrochemistry (DST)TargetWell Data – what we wanted to evaluate and whyWell 103 – Field MethodsField Methods: �DrillingField Methods: �Well Set-up and TestingWell Data: Pressure Build-up DataWell Data: PermeabilityWell Data�Water Chemistry/QualityIsotope Geochemistry�(water and dissolved gas)Part I: Summary and ConclusionsPart II �Production / Development and RegulatoryResults Review:Water Act may be applicable��CBM Working Group / �Alberta Environment�EUB: ��1. Code of Practice�2. Div. Approval�3. No RepWater Well Distn. �Pressure vs. Depth�(Test-well 103)Piper Plot (water wells and 103)Part III: Regional ConsiderationsPressure / Hydraulic Head�lowermost Paskapoo - Ardley - Scollard Topo vs. Hydraulic HeadHydrostratigraphic Section B-B’Chemistry Piper Diagram�lowermost Paskapoo - Ardley - Scollard18O vs 2H�regional2HH2O vs. 2HCH4SYNTHESIS�Cross-section B-B’ SynthesisFlowSummary and ConclusionsThank you

    BackButton2: