Factpages Norwegian Offshore Directorate
Factpages Norwegian Offshore Directorate
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25.11.2024 - 01:30
Time of last synchronization with Norwegian Offshore Directorate's internal systems

25/11-20

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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.
    25/11-20
    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).
    WILDCAT
    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
    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.
    25/11-20
    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.
    Norsk Hydro Produksjon 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.
    826-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.
    16
    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,
    08.10.1995
    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.
    23.10.1995
    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.
    23.10.1997
    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.
    29.08.2003
    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.
    WILDCAT
    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.
    DRY
    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
    Kelly bushing elevation [m]
    Elevation of the rotary kelly bushing (RKB) above mean sea level.
    26.0
    Water depth [m]
    Depth in metres betweem mean sea level and sea floor.
    122.0
    Total depth (MD) [m RKB]
    Total measured length of wellbore from kelly bushing to total depth (driller's depth).
    1828.0
    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).
    1828.0
    Maximum inclination [°]
    Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.
    2.3
    Bottom hole temperature [°C]
    Estimated temperature at final total depth of the wellbore. Shown only for released wells. See discription.
    76
    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 CRETACEOUS
    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.
    TOR FM
    Geodetic datum
    Reference system for coordinates. Example of legal values: ED50.
    ED50
    NS degrees
    Geographic coordinate of the wellhead, north-south degrees.
    59° 8' 44.62'' N
    EW degrees
    Geographic coordinate of the wellhead, east-west degrees.
    2° 33' 44.27'' E
    NS UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, north-south.
    6556512.65
    EW UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, east-west.
    474958.17
    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.
    2667
  • Wellbore history

    General
    Well 25/11-20 is located East of the Southern segment of the Grane field. The primary objectives of well 25/11-20 were to prove oil resources within reach of the Grane field production unit that can be produced through the Grane field installation and to test the geological and geophysical models for non-mounded Paleocene sands within the Licence area. The secondary objectives of well 25/11-20 were to define areas in the licence which can be relinquished and to reduce the uncertainties associated with the surrounding prospects. The well location was selected to provide an accurate seismic tie, i.e. an area with minimal compaction effects and away from faults, in an area where there are indications of a thick sand on the seismic data.
    Operations and results
    Well 25/11-20 was spudded with the semi-submersible installation "Treasure Saga" on 8 October1995 and drilled to TD at 1828 m in limestones of the Late Cretaceous Tor Formation. The well was drilled water based with seawater and hi-vis bentonite sweeps down to 1254 m and with KCl / Polymer from 1254 m to TD. Unpredicted boulders were encountered at 152 m to 157 m, causing low ROP and extra work to keep the inclination small, otherwise no significant problems were encountered during drilling. Shallow gas was not predicted and not observed
    No sands or shows were encountered in the Rogaland Group. An internal high acoustic impedance shale was present at depth 1683 m to 1705 m where Heimdal sands were prognosed. The seismic response for this shale in the SOF data set was similar to the response for the Heimdal sand in the Grane Field. Four cores were cut between 1661 m and 1719.5 m in the Balder, Sele, Lista, and Våle Formations. Coring was stopped 20 m under the prognosed top of the main sand. The well was permanently abandoned on 23 October 1995 as a dry hole.
    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]
    1260.00
    1828.00
  • 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
    1661.0
    1678.3
    [m ]
    2
    1679.5
    1697.1
    [m ]
    3
    1697.5
    1708.3
    [m ]
    4
    1711.5
    1719.5
    [m ]
    Cores at the Norwegian Offshore Directorate
    Total core sample length [m]
    53.7
    Cores at the Norwegian Offshore Directorate
    Cores available for sampling?
    YES
  • Core photos

    Core photos
    Core photo at depth: 1661-1666m
    Core photo at depth: 1666-1671m
    Core photo at depth: 1671-1676m
    Core photo at depth: 1676-1678m
    Core photo at depth: 1679-1684m
    1661-1666m
    1666-1671m
    1671-1676m
    1676-1678m
    1679-1684m
    Core photo at depth: 1684-1689m
    Core photo at depth: 1689-1694m
    Core photo at depth: 1694-1697m
    Core photo at depth: 1697-1702m
    Core photo at depth: 1702-1707m
    1684-1689m
    1689-1694m
    1694-1697m
    1697-1702m
    1702-1707m
    Core photo at depth: 1707-1708m
    Core photo at depth: 1711-1716m
    Core photo at depth: 1716-1719m
    Core photo at depth: 1747-1750m
    Core photo at depth:  
    1707-1708m
    1711-1716m
    1716-1719m
    1747-1750m
  • 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
    SURF.COND.
    30
    209.0
    36
    209.0
    0.00
    LOT
    INTERM.
    13 3/8
    1254.0
    17 1/2
    1254.0
    0.00
    LOT
    OPEN HOLE
    1828.0
    8 1/2
    1828.0
    1.87
    LOT
  • Logs

    Logs
    Log type
    Log top depth [m]
    Log bottom depth [m]
    CST GR
    1550
    1784
    CST GR
    1550
    1765
    DLL MSFL DSI LDL CNL GR SP AMS
    1197
    1671
    DLL MSFL DSI LDL CNL GR SP AMS
    1612
    1827
    MWD - GR RES DIR
    148
    1828
    VSP GR AMS
    243
    1818
  • Lithostratigraphy

  • Composite logs

    Composite logs
    Document name
    Document format
    Document size [MB]
    pdf
    0.28
  • 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
    7.20
  • Drilling mud

    Drilling mud
    Depth MD [m]
    Mud weight [g/cm3]
    Visc. [mPa.s]
    Yield point [Pa]
    Mud type
    Date measured
    1254
    1.21
    13.0
    WATER BASED
    1661
    1.28
    21.0
    WATER BASED
    1679
    1.28
    20.0
    WATER BASED
    1711
    1.28
    17.0
    WATER BASED
    1789
    1.28
    16.0
    WATER BASED
    1828
    1.28
    18.0
    WATER BASED
  • Palynological slides at the Norwegian Offshore Directorate

    Palynological slides at the Norwegian Offshore Directorate
    Sample depth
    Depth unit
    Sample type
    Laboratory
    1260.0
    [m]
    DC
    RRI
    1280.0
    [m]
    DC
    RRI
    1300.0
    [m]
    DC
    RRI
    1320.0
    [m]
    DC
    RRI
    1340.0
    [m]
    DC
    RRI
    1360.0
    [m]
    DC
    RRI
    1380.0
    [m]
    DC
    RRI
    1400.0
    [m]
    DC
    RRI
    1420.0
    [m]
    DC
    RRI
    1440.0
    [m]
    DC
    RRI
    1460.0
    [m]
    DC
    RRI
    1500.0
    [m]
    DC
    RRI
    1520.0
    [m]
    DC
    RRI
    1540.0
    [m]
    DC
    RRI
    1550.0
    [m]
    SWC
    RRI
    1575.0
    [m]
    SWC
    RRI
    1600.0
    [m]
    SWC
    RRI
    1625.0
    [m]
    SWC
    RRI
    1640.0
    [m]
    SWC
    RRI
    1645.0
    [m]
    SWC
    RRI
    1645.0
    [m]
    DC
    RRI
    1650.0
    [m]
    DC
    RRI
    1650.0
    [m]
    SWC
    RRI
    1652.0
    [m]
    SWC
    RRI
    1660.0
    [m]
    SWC
    RRI
    1660.0
    [m]
    DC
    RRI
    1663.0
    [m]
    C
    RRI
    1666.0
    [m]
    C
    RRI
    1669.0
    [m]
    C
    RRI
    1672.0
    [m]
    C
    RRI
    1675.0
    [m]
    C
    RRI
    1678.0
    [m]
    C
    RRI
    1681.0
    [m]
    C
    RRI
    1684.0
    [m]
    C
    RRI
    1687.0
    [m]
    C
    RRI
    1688.0
    [m]
    C
    RRI
    1691.0
    [m]
    C
    RRI
    1695.0
    [m]
    C
    RRI
    1700.0
    [m]
    C
    RRI
    1706.0
    [m]
    C
    RRI
    1711.0
    [m]
    C
    RRI
    1716.0
    [m]
    C
    RRI
    1719.0
    [m]
    C
    RRI
    1721.0
    [m]
    SWC
    RRI
    1728.0
    [m]
    SWC
    RRI
    1735.0
    [m]
    SWC
    RRI
    1737.0
    [m]
    SWC
    RRI
    1739.0
    [m]
    SWC
    RRI
    1740.0
    [m]
    SWC
    RRI
    1743.0
    [m]
    SWC
    RRI
    1745.0
    [m]
    SWC
    RRI
    1747.0
    [m]
    SWC
    RRI
    1747.0
    [m]
    DC
    RRI
    1750.0
    [m]
    SWC
    RRI
    1755.0
    [m]
    SWC
    RRI
    1758.0
    [m]
    SWC
    RRI
    1762.0
    [m]
    DC
    RRI
    1763.0
    [m]
    SWC
    RRI
    1775.0
    [m]
    DC
    RRI
    1780.0
    [m]
    DC
    RRI
    1792.0
    [m]
    DC
    RRI
    1802.0
    [m]
    DC
    RRI
    1812.0
    [m]
    DC
    RRI