Factpages Norwegian Offshore Directorate
Factpages Norwegian Offshore Directorate
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22.12.2024 - 01:25
Time of last synchronization with Norwegian Offshore Directorate's internal systems

31/1-2 A

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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.
    31/1-2 A
    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.
    P&A
    Press release
    Multilateral
    Indicator telling if the parent well is multilateral, meaning it has more than one branch radiating from the main borehole. Example of legal values: YES, NO. See also Norwegian Offshore Directorate guidelines for designation of wells and wellbores.
    NO
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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
    Well name
    Official name of the parent well for the wellbore based on Norwegian Offshore Directorate guidelines for designation of wells and wellbores.
    31/1-2
    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.
    Equinor Energy AS
    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.
    1837-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.
    17
    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,
    13.01.2021
    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.
    29.01.2021
    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.
    29.01.2023
    Plugged and abondon date
    Date when the P&A-operations of the wellbore was finished, as reported by the operator to the Norwegian Offshore Directorate throught DDRS (Daily Drilling Reporting System). Only applied once pr. wellhead/surface location.
    29.01.2021
    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.
    29.01.2023
    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
    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.
    MIDDLE 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.
    ETIVE FM
    2nd level with HC, age
    Age of lithostratigraphic unit, 2nd level, where hydrocarbons were encountered. Examples of legal values: CRETACEOUS, EARLY CRETACEOUS, LATE JURASSIC, EOCENE.
    MIDDLE JURASSIC
    2nd level with HC, formation
    Name of lithostartigraphic unit, 2nd 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.
    OSEBERG FM
    Kelly bushing elevation [m]
    Elevation of the rotary kelly bushing (RKB) above mean sea level.
    31.0
    Water depth [m]
    Depth in metres betweem mean sea level and sea floor.
    349.0
    Total depth (MD) [m RKB]
    Total measured length of wellbore from kelly bushing to total depth (driller's depth).
    3876.0
    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).
    3482.9
    Maximum inclination [°]
    Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.
    47.8
    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.
    EARLY JURASSIC
    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.
    COOK FM
    Geodetic datum
    Reference system for coordinates. Example of legal values: ED50.
    ED50
    NS degrees
    Geographic coordinate of the wellhead, north-south degrees.
    60° 57' 4.79'' N
    EW degrees
    Geographic coordinate of the wellhead, east-west degrees.
    3° 18' 33.26'' E
    NS UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, north-south.
    6757565.95
    EW UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, east-west.
    516751.83
    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.
    9179
  • Wellbore history

    General
    Well 31/1-2 A is a geological side-track to well 31/1-2 S, which discovered oil and gas in the Brent Group and upper part of the Drake Formation in the Røver Nord prospect. The well is located on the Lomre Terrace, 9 km north-west of the Troll Field in the North Sea . The primary objective was to appraise the Røver Nord discovery down-dip on the structure.
    Operations and results
    Appraisal well 31/1-2 A was kicked off at 1655 m in the primary well bore on 13 January 2021. It was drilled with the semi -submersible installation West Hercules to TD at 3876 m (3482.9 m TVD) m in the Early Jurassic Cook Formation. Operations proceeded without significant problems. The well was drilled with Versatec oil-based mud from kick-off to down to 3509 m and with Exploradril oil-based mud from 3509 m to TD.
    The Brent Group was encountered at 3586 m (3200 m TVD). Down to top Etive Formation at 3682 m (3293 m TVD RKB) the Brent Group consisted of mudstones with meter-thick sandstones and coal layers in the Ness Formation. The Etive and Oseberg formations were oil bearing. Oil shows (fluorescence and cut) were observed on sandstones above the Etive Formation up to the middle of the Tarbert Formation, otherwise there were no shows outside of the hydrocarbon-bearing Etive and Oseberg sandstones.
    No cores were cut. MDT fluid samples were taken at 3687.0 m (oil), 3712.5 m (oil), and 3734.5 m (water).
    The well was permanently abandoned on 29 January 2021 as an oil appraisal well.
    Testing
    No drill stem test was performed.
  • 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]
    1670.00
    3875.00
  • 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
    LINER
    13 3/8
    1655.0
    17 1/2
    1728.0
    1.59
    FIT
    LINER
    9 5/8
    3507.0
    12 1/4
    3509.0
    1.85
    LOT
  • Logs

    Logs
    Log type
    Log top depth [m]
    Log bottom depth [m]
    CMR NEXT C
    3570
    3815
    HGNS PEX ZAIT
    3507
    3876
    MDT GR
    3656
    3865
    MWD - GR RES
    3509
    3876
    MWD - RES GR NBGR
    1661
    3509
    NGI MSIP
    2950
    3858
    XLR GR
    3780
    3780
  • Lithostratigraphy

  • Drilling mud

    Drilling mud
    Depth MD [m]
    Mud weight [g/cm3]
    Visc. [mPa.s]
    Yield point [Pa]
    Mud type
    Date measured
    752
    1.25
    9.0
    11.5
    Glydril
    1700
    1.31
    29.0
    8.0
    Versatec
    2085
    1.35
    30.0
    7.5
    Versatec
    3516
    1.25
    15.0
    7.5
    Exploradrill
    3876
    1.25
    16.0
    9.0
    Exploradrill