Factpages Norwegian Offshore Directorate
Factpages Norwegian Offshore Directorate
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22.11.2024 - 09:09
Time of last synchronization with Norwegian Offshore Directorate's internal systems

7/12-8

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  • General information

    General information
    Attribute Value
    Wellbore name
    Official name of wellbore based on Norwegian Offshore Directorate guidelines for designation of wells and wellbores.
    7/12-8
    Type
    Wellbore type. Legal values: EXPLORATION, DEVELOPMENT, OTHER (see 'Purpose' for more information)
    EXPLORATION
    Purpose
    Final classification of the wellbore.

    Legal values for exploration wellbores:
    WILDCAT, APPRAISAL, WILDCAT-CCS, APPRAISAL-CCS.

    Legal values for development wellbores:
    OBSERVATION, PRODUCTION, INJECTION, INJECTION-CCS, OBSERVATION-CCS.

    Legal values for other wellbores:
    SOIL DRILLING (drilling in connection with track surveys and other subsurface surveys to investigate the soil conditions prior to placement of facilities),
    SHALLOW GAS (drilling to investigate shallow gas before the first 'real' drilling on the location),
    PILOT (drilling to investigate the geology and fluid connectors for location of the main wellbore),
    SCIENTIFIC (drilling according to Law of Scientific research and exploration),
    STRATIGRAPHIC (driling according to Law of Petroleum activities §2-1).
    APPRAISAL
    Status
    Status for the wellbore. Legal values are:

    BLOWOUT: A blowout has occurred in the well.
    CLOSED: A development wellbore that has been closed in a shorter or longer periode. Also applies to development wellbores where drilling is completed, but production/injection has not yet been reported.
    DRILLING: The well is in the drilling phase - can be active drilling, logging, testing or plugging,
    JUNKED: The drilling operation has been terminated due to technical problems.
    P&A: Exploration: The well is plugged and abandoned, and can not be reentered for further use. Development wells: The production/injection from/to the well is stopped and the well is plugged. The wellhead is removed or else made unavailable for further well operations.
    PLUGGED: The wellbore has been plugged, but the upper parts of the wellbore can be re-used. A sidetrack might be drilled at a later stage.
    PRODUCING: It was produced from the wellbore at the time of the operators last monthly report to the Norwegian Offshore Directorate.
    INJECTING: It was injected to the wellbore at the time of the operators last monthly report to the Norwegian Offshore Directorate.
    PREDRILLED: The upper part of the well has been drilled, usually as part of a batch-drilling campaign covering several wellbores.
    RE-CLASS TO DEV: Exploration wellbore that is reclassified to a development wellbore.
    RE-CLASS TO TEST: Exploration wellbore that is reclassified to test production.
    SUSPENDED: The drilling operation in the wellbore has been temporarily stopped. The current plan is to continue drilling later on.
    SUSPENDED
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    Main area
    Name of the area on the Norwegian Continental Shelf where the wellbore is located. Legal values: BARENTS SEA, NORWEGIAN SEA, NORTH SEA.
    NORTH SEA
    Field
    Name of the field the wellbore is related to.
    Discovery
    Name of the discovery the wellbore is related to.
    Well name
    Official name of the parent well for the wellbore based on Norwegian Offshore Directorate guidelines for designation of wells and wellbores.
    7/12-8
    Seismic location
    Position of spud location on seismic survey lines. SP: shotpoint.
    LINE 143 SP 470
    Production licence
    Official designation of the production licence the wellbore was drilled or planned to be drilled from ( well head posistion).
    Drilling operator
    Name of the licensee starting the drilling operation on behalf of the active production license (well head position). This will usually equal the operator of the production license.
    BP Norway Limited U.A.
    Drill permit
    The drilling permit number together with the version of the drilling permit as stated in the drilling permit granted by the Norwegian Offshore Directorate.
    590-L
    Drilling facility
    Norwegian Offshore Directorate's name of the facility which the wellbore was drilled from.
    Drilling days
    Number of days from wellbore entry to wellbore completion.
    81
    Entered date
    The date when he wellbore was spudded. For sidetracks: The date when new formation was drilled by kicking off from the mother-wellbore,
    04.10.1988
    Completed date
    Exploration wellbores from moveable facilities:
    For floating facilities - date when anchor handling is started. For jackups - date the jacking-down started. Exploration wellbores from fixed facilities and all development wellbores:
    Date when the wellbore is at total depth, and last casing, liner or screen is set. In case of immediate plugging of the wellbore, completed date equals the date the last plug i set in the wellbore.
    Date when the wellbore is at total depth, and last casing, liner or screen is set. In case of immediate plugging of the wellbore, completed date equals the date the last plug i set in the wellbore.
    23.12.1988
    Release date
    Date when raw data which has been reported to the authorities from the wellbore is not confidential any longer. Normally 2 years after finishing the drilling. May be earlier if the area of the production license is relinquished.
    23.12.1990
    Publication date
    Date quality control of the wellbore information was completed, so it can be published on the internet as a 'Well Data Summary Sheet' wellbore with more information available than other wellbores.
    28.03.2014
    Purpose - planned
    Pre-drill purpose of the wellbore. Legal values for exploration wellbores: WILDCAT, APPRAISAL, WILDCAT-CCS, APPRAISAL-CCS. Example of legal values for development wellbores: OBSERVATION, PRODUCTION, INJECTION.
    APPRAISAL
    Reentry
    Status whether the wellbore has been re-entered (YES) or not (NO). Re-entered wellbores are not included in the count when wellbores are presented in statistical overviews.
    NO
    Content
    For exploration wellbores, status of discovery.

    Legal values:
    DRY, SHOWS (trace amounts of hydrocarbons), GAS, GAS/CONDENSATE, OIL or OIL/GAS.
    SHOWS (GAS SHOWS, OIL SHOWS or OIL/GAS SHOWS) are detected as fluorescent cut (organic extract), petroleum odour, or visual stain on cuttings or cores, or as increased gas reading on the mud-loggers gas detection equipment.
    Legal values for WILDCAT-CCS and APPRAISAL-CCS: WATER

    For development wellbores, type of produced/injected fluid.
    Legal values:
    WATER, CUTTINGS, NOT AVAILABLE, OIL, GAS/CONDENSATE, OIL/GAS, CO2, GAS, WATER/GAS, NOT APPLICABLE.
    OIL
    Discovery wellbore
    Indicator which tells if the wellbore made a new discovery. Legal values: YES, NO. Prior to press-release or other information regarding drilling results, the indicator will be “NO” as a default.
    NO
    1st level with HC, age
    Age of lithostratigraphic unit, 1st level, where hydrocarbons were encountered. Examples of legal values: CRETACEOUS, EARLY CRETACEOUS, LATE JURASSIC, EOCENE. See also Norwegian Offshore Directorate bulletins.
    LATE JURASSIC
    1st level with HC, formation
    Name of lithostartigraphic unit, 1st level, where hydrocarbons were encountered. Shown only for released wells. Examples of legal values: BASEMENT, COOK FM, EKOFISK FM, HEIMDAL FM, SANDNES FM, SOGNEFJORD FM, TARBERT FM, BRENT GP. See also Norwegian Offshore Directorate bulletins.
    ULA FM
    Kelly bushing elevation [m]
    Elevation of the rotary kelly bushing (RKB) above mean sea level.
    25.0
    Water depth [m]
    Depth in metres betweem mean sea level and sea floor.
    70.0
    Total depth (MD) [m RKB]
    Total measured length of wellbore from kelly bushing to total depth (driller's depth).
    3900.0
    Final vertical depth (TVD) [m RKB]
    Vertical elevation from total depth to kelly bushing. Shown only for released wells. Referred to as true vertical depth (TVD).
    3898.0
    Maximum inclination [°]
    Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.
    5.7
    Bottom hole temperature [°C]
    Estimated temperature at final total depth of the wellbore. Shown only for released wells. See discription.
    151
    Oldest penetrated age
    Age (according to Geologic Time Scale 2004 by F. M. Gradstein, et al. (2004)) of the oldest penetrated formation. May differ from age at TD for example in deviated wellbores. Examples of legal values: CRETACEOUS, EARLY CRETACEOUS, LATE JURASSIC, EARLY PERMIAN, EARLY TRIASSIC, EOCENE.
    LATE TRIASSIC
    Oldest penetrated formation
    Name of the oldest lithostratigraphic unit penetrated by the wellbore. Shown only for released wells. In most wellbores this is formation or group at total depth. May differ from formation or group at TD for example in wellbores drilled with high deviation or through faults. Examples of legal values: AMUNDSEN FM, BALDER FM, BASEMENT, BLODØKS FM, BRYNE FM, BURTON FM, COOK FM, DRAKE FM, DRAUPNE FM, EKOFISK FM, DUNLIN GP.
    SKAGERRAK FM
    Geodetic datum
    Reference system for coordinates. Example of legal values: ED50.
    ED50
    NS degrees
    Geographic coordinate of the wellhead, north-south degrees.
    57° 5' 1.28'' N
    EW degrees
    Geographic coordinate of the wellhead, east-west degrees.
    2° 53' 52.26'' E
    NS UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, north-south.
    6326848.38
    EW UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, east-west.
    493808.24
    UTM zone
    Universal Transverse Mercator zone. Examples of legal values: 31, 32, 33, 34.
    31
    NPDID wellbore
    Norwegian Offshore Directorate's unique id for the wellbore.
    1311
  • Wellbore history

    General
    Well 7/12-8 was drilled on the south eastern flank of the Ula Field in the North Sea. The well was drilled to evaluate the reservoir potential of the south eastern sector of the Field and to assist target future water injection wells. To enable a full evaluation of the reservoir the lower Ula Formation and the underlying Triassic section were penetrated.
    Operations and results
    Appraisal well 7/12-8 was spudded with the semi-submersible installation Vildkat Explorer on 3 October 1988 and drilled to TD at 3900 m in the Triassic Skagerrak Formation. Drilling down to top reservoir proceeded without any significant problems. The well was drilled with seawater and bentonite down to 167 m, with seawater/bentonite/spercell/CMC EHV mud from 167 to 955 m, with KCl/polymer mud from 955 m to 3721 m, and with oil based Safemul mud from 3721 m to TD.
    Top Mandal Formation was encountered at 3640 m, top Farsund Formation at 3663 m, and top Ula Formation at 3718 m, 78 m higher than prognosed. RFT measurements showed a pressure barrier at ca 3770 m. There was oil down to the barrier and water below. An effective oil/water contact was difficult to identify. The saturation profile across interval 3770 - 3796 is interpreted as water influx from the aquifer following production from the field since 1986. The RFT results supported that the Ula reservoir at the 7/12-8 location was depleted and in pressure communication with the crestal producing part of the Ula Field. There were no signs of hydrocarbons in the underlying Triassic.
    One core was cut in the Ula Formation from 3724.0 to 3750.5 m. Segregated RFT fluid samples were taken at 3772 m (water and oil) and 3808.5 m (water and OBM).
    The well was suspended on 23 December 1988 as an oil appraisal.
    Testing
    One Drill Stem Test was performed in the Ula Formation in the interval 3719 to 3756 m flowed 274 Sm3/d of oil and 21800 Sm3/d of gas through a 254 mm choke. The GOR was 79 Sm3/Sm3. Maximum H2S and CO2 was 0 ppm and 2.5 %vol, respectively. Final BHT was 146.1 deg C. Two water injection tests followed the production test, the first over interval 3719 m to 3756 m and the second overt the interval 3719 to 3783 m.
    r
  • Cuttings at the Norwegian Offshore Directorate

    Cuttings at the Norwegian Offshore Directorate
    Cuttings available for sampling?
    YES
    Cuttings at the Norwegian Offshore Directorate
    Cutting sample, top depth [m]
    Cutting samples, bottom depth [m]
    1500.00
    3897.00
  • Cores at the Norwegian Offshore Directorate

    Cores at the Norwegian Offshore Directorate
    Core sample number
    Core sample - top depth
    Core sample - bottom depth
    Core sample depth - uom
    1
    3724.5
    3750.0
    [m ]
    Cores at the Norwegian Offshore Directorate
    Total core sample length [m]
    25.5
    Cores at the Norwegian Offshore Directorate
    Cores available for sampling?
    YES
  • Core photos

    Core photos
    Core photo at depth: 3724-3729m
    Core photo at depth: 3729-3734m
    Core photo at depth: 3734-3739m
    Core photo at depth: 3739-3744m
    Core photo at depth: 3744-3749m
    3724-3729m
    3729-3734m
    3734-3739m
    3739-3744m
    3744-3749m
    Core photo at depth: 3749-3750m
    Core photo at depth:  
    Core photo at depth:  
    Core photo at depth:  
    Core photo at depth:  
    3749-3750m
  • Lithostratigraphy

  • Documents – reported by the production licence (period for duty of secrecy expired)

    Documents – reported by the production licence (period for duty of secrecy expired)
    Document name
    Document format
    Document size [MB]
    pdf
    11.86
  • Drill stem tests (DST)

    Drill stem tests (DST)
    Test number
    From depth MD
    [m]
    To depth MD
    [m]
    Choke size
    [mm]
    1.0
    3719
    3783
    16.0
    Drill stem tests (DST)
    Test number
    Final shut-in pressure
    [MPa]
    Final flow pressure
    [MPa]
    Bottom hole pressure
    [MPa]
    Downhole temperature
    [°C]
    1.0
    Drill stem tests (DST)
    Test number
    Oil
    [Sm3/day]
    Gas
    [Sm3/day]
    Oil density
    [g/cm3]
    Gas grav. rel.air
    GOR
    [m3/m3]
    1.0
    274
    22000
    79
  • Logs

    Logs
    Log type
    Log top depth [m]
    Log bottom depth [m]
    0
    0
    BGL GR
    952
    2344
    BHC GR
    3725
    3770
    CBL VDL GR
    1500
    3768
    CST GR
    2350
    3721
    CST GR
    3796
    3893
    DIL BHC GR
    2340
    3726
    DIL BHC GR
    3726
    3792
    DIL BHC GR
    3794
    3903
    DIL LSS GR
    167
    350
    DIL LSS GR
    952
    2342
    LDL CNL GR
    3793
    3902
    LDL CNL NGL
    3716
    3794
    MWD
    3710
    3788
    NGT
    3716
    3794
    OBT GR
    3793
    3902
    RFTB HP GR
    3730
    3780
    RFTB HP GR
    3795
    3887
    SAT VELOCITY
    300
    3900
  • Casing and leak–off tests

    Casing and leak–off tests
    Casing type
    Casing diam.
    [inch]
    Casing depth
    [m]
    Hole diam.
    [inch]
    Hole depth
    [m]
    LOT/FIT mud eqv.
    [g/cm3]
    Formation test type
    CONDUCTOR
    30
    167.0
    32
    171.0
    0.00
    LOT
    SURF.COND.
    20
    951.0
    26
    957.0
    1.63
    LOT
    INTERM.
    13 3/8
    2338.0
    17 1/2
    2350.0
    1.97
    LOT
    INTERM.
    9 5/8
    3712.0
    12 1/4
    3721.0
    2.24
    LOT
    LINER
    7
    3787.0
    8 1/2
    3788.0
    2.06
    LOT
    OPEN HOLE
    3900.0
    6
    3900.0
    0.00
  • Drilling mud

    Drilling mud
    Depth MD [m]
    Mud weight [g/cm3]
    Visc. [mPa.s]
    Yield point [Pa]
    Mud type
    Date measured
    559
    1.25
    22.5
    12.0
    WATER BASED
    11.10.1988
    957
    1.30
    23.5
    13.0
    WATER BASED
    11.10.1988
    957
    1.30
    19.0
    9.6
    WATER BASED
    11.10.1988
    957
    1.30
    18.5
    13.4
    WATER BASED
    11.10.1988
    957
    1.30
    23.5
    13.0
    WATER BASED
    11.10.1988
    957
    1.30
    23.5
    13.0
    WATER BASED
    19.10.1988
    957
    1.30
    24.0
    13.4
    WATER BASED
    19.10.1988
    1026
    1.42
    32.0
    10.6
    OIL BASED
    19.10.1988
    1336
    1.52
    30.0
    10.1
    OIL BASED
    19.10.1988
    1484
    1.52
    42.0
    9.6
    OIL BASED
    19.10.1988
    1695
    1.52
    54.0
    16.3
    OIL BASED
    24.10.1988
    1945
    1.52
    59.5
    14.9
    OIL BASED
    24.10.1988
    2050
    1.54
    57.5
    14.9
    OIL BASED
    24.10.1988
    2145
    1.54
    59.0
    14.9
    OIL BASED
    24.10.1988
    2316
    1.55
    63.0
    17.3
    OIL BASED
    24.10.1988
    3341
    1.56
    44.5
    10.1
    WATER BASED
    11.11.1988
    3427
    1.56
    44.0
    10.6
    WATER BASED
    11.11.1988
    3495
    6.01
    45.5
    10.6
    WATER BASED
    17.11.1988
    3567
    1.56
    44.5
    10.6
    WATER BASED
    17.11.1988
    3629
    1.58
    44.0
    10.6
    WATER BASED
    17.11.1988
    3670
    1.58
    43.5
    10.1
    WATER BASED
    17.11.1988
    3709
    1.58
    44.5
    10.1
    WATER BASED
    17.11.1988
    3713
    1.58
    45.5
    10.6
    WATER BASED
    17.11.1988
    3716
    1.58
    45.0
    10.6
    WATER BASED
    17.11.1988
    3717
    1.58
    45.0
    11.5
    WATER BASED
    21.11.1988
    3719
    1.58
    44.5
    12.0
    WATER BASED
    21.11.1988
    3720
    1.58
    42.5
    12.0
    WATER BASED
    21.11.1988
    3721
    1.58
    41.0
    9.6
    WATER BASED
    22.11.1988
    3721
    1.58
    42.0
    11.5
    WATER BASED
    22.11.1988
    3721
    1.58
    42.0
    11.5
    WATER BASED
    24.11.1988
    3721
    1.58
    46.0
    11.5
    WATER BASED
    25.11.1988
    3721
    1.58
    22.0
    24.0
    WATER BASED
    28.11.1988
    3723
    0.91
    9.6
    6.0
    WATER BASED
    28.11.1988
    3751
    0.92
    9.6
    8.0
    OIL BASED
    28.11.1988
    3765
    0.93
    10.8
    9.0
    OIL BASED
    30.11.1988
    3781
    0.94
    16.0
    2.9
    WATER BASED
    13.12.1988
    3781
    0.95
    20.5
    3.8
    WATER BASED
    16.12.1988
    3781
    0.95
    20.5
    3.4
    WATER BASED
    16.12.1988
    3781
    0.94
    20.0
    3.4
    WATER BASED
    19.12.1988
    3781
    0.96
    19.0
    2.9
    WATER BASED
    19.12.1988
    3781
    0.95
    22.0
    3.8
    WATER BASED
    21.12.1988
    3781
    0.96
    24.0
    3.6
    WATER BASED
    21.12.1988
    3781
    0.96
    22.0
    3.4
    WATER BASED
    21.12.1988
    3788
    0.94
    9.6
    8.0
    OIL BASED
    30.11.1988
    3788
    0.94
    10.8
    7.0
    OIL BASED
    01.12.1988
    3788
    0.95
    11.0
    8.0
    OIL BASED
    02.12.1988
    3788
    1.40
    37.5
    5.3
    WATER BASED
    06.12.1988
    3900
    1.42
    47.5
    5.3
    WATER BASED
    09.12.1988
    3900
    1.42
    47.0
    5.8
    WATER BASED
    09.12.1988
    3900
    1.40
    39.5
    5.3
    WATER BASED
    13.12.1988
    3900
    0.00
    18.0
    2.9
    WATER BASED
    13.12.1988
    3900
    0.94
    18.5
    2.4
    WATER BASED
    13.12.1988
    3900
    1.40
    45.0
    5.8
    WATER BASED
    06.12.1988
    3900
    1.41
    40.0
    4.8
    WATER BASED
    07.12.1988
    3900
    0.95
    13.5
    3.4
    WATER BASED
    13.12.1988
  • Pressure plots

    Pressure plots
    The pore pressure data is sourced from well logs if no other source is specified. In some wells where pore pressure logs do not exist, information from Drill stem tests and kicks have been used. The data has been reported to the NPD, and further processed and quality controlled by IHS Markit.
    Pressure plots
    Document name
    Document format
    Document size [MB]
    pdf
    0.21