Factpages Norwegian petroleum directorate
NPD          Norsk

25/11-12

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  • General information

    General information
    Attribute Value
    Wellbore name
    Official name of wellbore based on NPD guidelines for designation of wells and wellbores.
    25/11-12
    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 NPD.
    INJECTING: It was injected to the wellbore at the time of the operators last monthly report to the NPD.
    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
    Factmaps in new window
    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 NPD guidelines for designation of wells and wellbores.
    25/11-12
    Seismic location
    Position of spud location on seismic survey lines. SP: shotpoint.
    BALMG 173 SP: 240.
    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.
    Esso Exploration and Production Norway A/S
    Drill permit
    The drilling permit number together with the version of the drilling permit as stated in the drilling permit granted by the NPD.
    281-L
    Drilling facility
    NPD's name of the facility which the wellbore was drilled from.
    Drilling days
    Number of days from spud to completed. The first and last days of the operation is included in the count. Days where the drilling operations has been suspende, is not included. Days used for predrilling is not included. These are made available where applicable.
    20
    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,
    18.04.1981
    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.
    07.05.1981
    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.
    07.05.1983
    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.
    17.06.2011
    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.
    SHOWS
    Discovery wellbore
    Indicator which telles if the wellbore made a new discovery. Legal values: YES, NO.
    NO
    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.
    127.0
    Total depth (MD) [m RKB]
    Total measured length of wellbore from kelly bushing to total depth (driller's depth).
    1918.0
    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).
    1918.0
    Maximum inclination [°]
    Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.
    1.4
    Bottom hole temperature [°C]
    Estimated temperature at final total depth of the wellbore. Shown only for released wells. See discription.
    60
    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.
    PALEOCENE
    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.
    EKOFISK FM
    Geodetic datum
    Reference system for coordinates. Example of legal values: ED50.
    ED50
    NS degrees
    Geographic coordinate of the wellhead, north-south degrees.
    59° 12' 2.61'' N
    EW degrees
    Geographic coordinate of the wellhead, east-west degrees.
    2° 22' 51.74'' E
    NS UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, north-south.
    6562718.97
    EW UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, east-west.
    464645.01
    UTM zone
    Universal Transverse Mercator zone. Examples of legal values: 31, 32, 33, 34.
    31
    NPDID wellbore
    NPD's unique id for the wellbore.
    372
  • Wellbore history

    General
    Well 25/11-12 was drilled to appraise the Balder Field on the Utsira High in the North Sea. The objective was to establish the presence of a thick accumulation of oil sand in the north-eastern part of the Balder Field, and evaluate the geologic concept of sand-shale distribution and the reservoir quality of the Paleocene sands. The top of the reservoir was anticipated to be at 1717 m TVD MSL.
    Operations and results
    Appraisal well 25/11-12 was spudded with the semi-submersible installation Glomar Biscay II on 18 April 1981 on and drilled to TD at 1918 m in the Danian age chalk of the Ekofisk Formation. The well was drilled with seawater/gel/Lignosulphonate mud.
    The Sele Formation had thin stringers of sand with oil shows, but no significant Paleocene sands were developed above the Heimdal Formation in this well. Massive Paleocene Heimdal Formation sands were encountered at 1784.5 m (1759.5 m TVD MSL) and 1860 m (1835 m TVD MSL). The upper sand is 65 m thick and had oil shows evident by sidewall cores at 1785 m and 1786 m. The lower sand is 20 m thick and was entirely water-bearing with no shows. The Balder Field oil/water contact is generally thought to be at 1785 m (1760 m).
    No cores were cut and no wire line fluid samples were taken.
    The well was permanently abandoned on 7 May 1981as a dry well with shows.
    Testing
    No drill stem test was performed.
  • Cuttings at the NPD

    Cuttings at the NPD
    Cuttings available for sampling?
    YES
    Cuttings at the NPD
    Cutting sample, top depth [m]
    Cutting samples, bottom depth [m]
    230.00
    1914.00
  • Palynological slides at the NPD

    Palynological slides at the NPD
    Sample depth
    Depth unit
    Sample type
    Laboratory
    1595.0
    [m]
    SWC
    1610.0
    [m]
    SWC
    1625.0
    [m]
    SWC
    1631.5
    [m]
    SWC
    1636.5
    [m]
    SWC
    1653.0
    [m]
    SWC
    1661.0
    [m]
    SWC
    1664.0
    [m]
    SWC
    1667.5
    [m]
    SWC
    1672.0
    [m]
    SWC
    1679.0
    [m]
    SWC
    1697.5
    [m]
    SWC
    1711.5
    [m]
    SWC
    1722.0
    [m]
    SWC
    1727.0
    [m]
    SWC
    1731.0
    [m]
    DC
    1734.0
    [m]
    SWC
    1737.0
    [m]
    DC
    1745.0
    [m]
    DC
    1745.0
    [m]
    SWC
    1749.0
    [m]
    SWC
    1762.0
    [m]
    SWC
    1772.0
    [m]
    SWC
    1779.0
    [m]
    SWC
    1782.0
    [m]
    SWC
    1783.0
    [m]
    SWC
    1784.0
    [m]
    SWC
    1809.0
    [m]
    SWC
    1827.5
    [m]
    SWC
    1839.0
    [m]
    SWC
    1854.0
    [m]
    SWC
    1858.5
    [m]
    SWC
    1862.5
    [m]
    SWC
    1877.0
    [m]
    SWC
    1879.5
    [m]
    SWC
    1882.0
    [m]
    SWC
    1889.0
    [m]
    SWC
    1894.5
    [m]
    SWC
    1898.0
    [m]
    SWC
    1901.0
    [m]
    SWC
    1903.0
    [m]
    SWC
  • 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
    1.17
    pdf
    6.23
  • Logs

    Logs
    Log type
    Log top depth [m]
    Log bottom depth [m]
    DEN NEU GR
    1290
    1918
    DIPLOG
    1295
    1917
    DLL MLL GR
    1295
    1918
    IEL BHC AC GR SP
    150
    1917
    SWC
    1595
    1909
    VELOCITY
    150
    1918
  • 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
    226.0
    36
    226.0
    0.00
    LOT
    INTERM.
    13 3/8
    446.5
    17 1/2
    460.0
    1.77
    LOT
    INTERM.
    9 5/8
    1301.0
    12 1/4
    1315.0
    1.75
    LOT
    OPEN HOLE
    1918.0
    8 1/2
    1918.0
    0.00
    LOT
  • Drilling mud

    Drilling mud
    Depth MD [m]
    Mud weight [g/cm3]
    Visc. [mPa.s]
    Yield point [Pa]
    Mud type
    Date measured
    340
    1.08
    47.0
    waterbased
    770
    1.10
    40.0
    waterbased
    1450
    1.18
    45.0
    waterbased
    1840
    1.19
    46.0
    waterbased