Factpages Norwegian Offshore Directorate
Factpages Norwegian Offshore Directorate
sodir.no          Norsk
31.10.2024 - 01:27
Time of last synchronization with Norwegian Offshore Directorate's internal systems

7/4-2

Export: PDF icon PDF
  • General information

    General information
    Attribute Value
    Wellbore name
    Official name of wellbore based on Norwegian Offshore Directorate guidelines for designation of wells and wellbores.
    7/4-2
    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
    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 Norwegian Offshore Directorate guidelines for designation of wells and wellbores.
    7/4-2
    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.
    Lundin Norway 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.
    1161-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.
    90
    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,
    15.12.2007
    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.
    13.03.2008
    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.
    13.03.2010
    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.
    13.03.2010
    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.
    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.
    43.0
    Water depth [m]
    Depth in metres betweem mean sea level and sea floor.
    82.0
    Total depth (MD) [m RKB]
    Total measured length of wellbore from kelly bushing to total depth (driller's depth).
    3459.0
    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).
    3458.0
    Maximum inclination [°]
    Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.
    3.3
    Bottom hole temperature [°C]
    Estimated temperature at final total depth of the wellbore. Shown only for released wells. See discription.
    153
    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 PERMIAN
    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.
    ZECHSTEIN GP
    Geodetic datum
    Reference system for coordinates. Example of legal values: ED50.
    ED50
    NS degrees
    Geographic coordinate of the wellhead, north-south degrees.
    57° 30' 13.05'' N
    EW degrees
    Geographic coordinate of the wellhead, east-west degrees.
    2° 18' 33.18'' E
    NS UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, north-south.
    6373803.68
    EW UTM [m]
    Universal Transverse Mercator coordinate of the wellhead, east-west.
    458603.25
    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.
    5683
  • Wellbore history

    General
    Well 7/4-2 was drilled on the Nemo prospect on the Jæren High in the North Sea. Two wells had previously been drilled for the evaluation of the Nemo structure. The 7/7-2 was drilled by Statoil in 1992 and discovered 19.5 m oil filled Ula Formation. No OWC was detected and no reliable pressure measurements were retrieved in the underlying Triassic Smith Bank Formation. Well 7/7-3 was drilled down flank to the SSW in 1993 and penetrated a 16.5 m Ula Formation which was water bearing with oil shows. The primary objective of the 7/4-2 Nemo well was to appraise the 7/7-2 oil discovery. This objective included determination of the OWC deeper than 3372 m (3371.1 m TVD RKB) oil down to in well 7/7-2; to verify the seismic interpretation and geological model for the Nemo discovery, including facies changes in the Farsund Formation; and finally to obtain fluid samples (oil and formation water). The secondary objective was to test the reservoir potential of the Triassic Smith Bank Formation.
    The well was designed as a potential future water injector.
    Operations and results
    Appraisal well 7/4-2 was spudded with the jack-up installation Mærsk Giant on 15 December 2007 and drilled to TD at 3459 m in the Late Permian Zechstein Group. A 9 7/8" pilot hole was drilled from the 30" conductor shoe at 208 m and down to 236 m when losses were discovered. A passage through the cement from the 30" conductor shoe to seabed allowed the pumped seawater to escape from the circulating system. While monitoring the losses when pumping at 3000 l/min, 42 m3/hr travelled unhindered behind the conductor to the seabed. Due to the severity of the losses a cement stinger was run in to 207 m and 37 m3 cement pumped to seal the passage and cure the losses. The well was drilled with Seawater and hi-vis pills down to 950 m, with Aquadril /KCl (glycol-) mud from 950 m to 1857 m, and with CarboSea oil based mud from 1857 m to TD.
    The top of the Jurassic reservoir Ula Formation was encountered at 3382 m, 7 meter deeper than prognosed. The seismic interpretation of a possible thickening of the reservoir, up to 54 m, towards the Triassic pod was not proven. The observed increased sediment thickness belongs to the non-reservoir Triassic Smith Bank Formation. Hence, the Ula Formation thickness of 18 m was penetrated. Pressure points taken from 3389 m to 3345.5 m (Ula Formation) varied from 632.73 bar to 633.69 bar. It gave an oil gradient of 0.076 bar/m equivalent to a density of 0.77 g/cc. The water density in the reservoir was derived from a sample (1.09 g/cc). From evaluation of the wire line logs, pressure points and sample analysis, the OWC was estimated to be found in the interval 3397 m to 3399 m MD RKB / 3396.1 m to 3398.1 m TVD RKB. Down to top Mandal Formation the gas composition was mainly C1 and there were no shows on cuttings. The entire Ula Formation sandstone and 4 m of the Skagerrak Formation had HC shows, from 3381 m to 3404 m. In the underlying Triassic sediments, no shows were seen.
    Two conventional cores were taken, from 3378.5 m to 3403.9 m and 3403.9 m to 3421.7 m with 97 % and 98 % recovery, respectively. RCI fluid samples were taken at three levels, 3392.5 m (oil), 3389 m (oil), and 3399.2 m (water).
    The well was plugged back and made ready for permanent abandonment on 27 February, abandoning also the plan to use it as a future injector. Gas bubbles were seen from the well crater. Analysis of the gas bubbles concluded that the gas was from shallow formations (biogenic gas), i.e. gas percolating between the 20" surface casing and 30" conductor, not gas from the reservoir. The rig waited on weather for14 days before jacking down, observing that the leak rate did not increase. The well was permanently abandoned on 13 March 2008 still with a small gas leak from the well crater. It is classified 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]
    240.00
    3459.00
  • 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
    3378.5
    3403.2
    [m ]
    2
    3403.9
    3421.4
    [m ]
    Cores at the Norwegian Offshore Directorate
    Total core sample length [m]
    42.2
    Cores at the Norwegian Offshore Directorate
    Cores available for sampling?
    YES
  • Oil samples at the Norwegian Offshore Directorate

    Oil samples at the Norwegian Offshore Directorate
    Test type
    Bottle number
    Top depth
    MD [m]
    Bottom depth
    MD [m]
    Fluid type
    Test time
    Samples available
    DST
    0.00
    3389.00
    YES
  • 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
    208.0
    36
    210.0
    0.00
    LOT
    SURF.COND.
    20
    950.0
    26
    950.0
    1.96
    LOT
    INTERM.
    13 3/8
    1848.0
    17 1/2
    1847.0
    1.91
    LOT
    INTERM.
    9 5/8
    3219.0
    12 1/4
    3229.0
    2.10
    LOT
    OPEN HOLE
    3450.0
    8 1/2
    3458.0
    0.00
    LOT
  • Logs

    Logs
    Log type
    Log top depth [m]
    Log bottom depth [m]
    HDIL XMAC ZDL CN SL WGI
    3214
    3455
    MWD LWD - DIR
    125
    213
    MWD LWD - GR RES DEN NEU SON DIR
    1857
    3226
    MWD LWD - GR RES DIR PWD
    213
    1857
    MWD LWD - GR RES DIR PWD
    3368
    3459
    RCI GR
    3379
    3408
    SST 500 GR
    847
    3407
  • Lithostratigraphy

  • Drilling mud

    Drilling mud
    Depth MD [m]
    Mud weight [g/cm3]
    Visc. [mPa.s]
    Yield point [Pa]
    Mud type
    Date measured
    319
    1.57
    water based
    550
    1.76
    38.0
    Oil Based
    1103
    1.45
    water based
    1400
    1.55
    water based
    1586
    1.55
    water based
    1826
    1.57
    water based
    1968
    1.71
    oil based
    2781
    1.71
    oil based
    3020
    1.95
    51.0
    Oil Based
    3028
    1.71
    oil based
    3147
    1.75
    oil based
    3226
    1.76
    oil based
    3278
    1.95
    oil based
    3403
    1.95
    oil based
    3459
    1.95
    oil based