Give whole or part of name of wellbore, licence, field, company, discovery etc. E.g. Aker, Statfjord, 24/12, ABP21014. The main content is not searched.
Official name of wellbore based on Norwegian Offshore Directorate guidelines for designation of wells and wellbores.
25/11-19 SR
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.
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 Norwegian Offshore Directorate.
811-L2
Drilling facility
Norwegian Offshore Directorate's name of the facility which the wellbore was drilled from.
Number of days from wellbore entry to wellbore completion.
6
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,
01.05.1997
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.
06.05.1997
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.
06.05.1999
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.
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.
YES
Reentry activity
Reason for reentry of the wellbore. Only relevant for exploration wellbores. Example of legal values: DRILLING, DRILLING/PLUGGING, LOGGING, PLUGGING, TESTING, TESTING/PLUGGING.
PLUGGING
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/GAS
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.
EOCENE
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.
INTRA BALDER FM SS
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.
PALEOCENE
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.
HERMOD FM
Kelly bushing elevation [m]
Elevation of the rotary kelly bushing (RKB) above mean sea level.
18.0
Water depth [m]
Depth in metres betweem mean sea level and sea floor.
129.0
Total depth (MD) [m RKB]
Total measured length of wellbore from kelly bushing to total depth (driller's depth).
2250.0
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).
2044.0
Maximum inclination [°]
Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.
39.16
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.
STATFJORD GP
Geodetic datum
Reference system for coordinates. Example of legal values: ED50.
ED50
NS degrees
Geographic coordinate of the wellhead, north-south degrees.
59° 12' 48.48'' N
EW degrees
Geographic coordinate of the wellhead, east-west degrees.
2° 24' 6.88'' E
NS UTM [m]
Universal Transverse Mercator coordinate of the wellhead, north-south.
6564126.95
EW UTM [m]
Universal Transverse Mercator coordinate of the wellhead, east-west.
Well 25/11-19 S was drilled on Licence 001, awarded in the first licence round in 1965. It was the last appraisal well on the Balder Field before it was decided to go ahead with Plan for Development in 1995. The well was located to penetrate the top reservoir of " Balder Mound 6" in a well-defined structurally high position. The primary target was a massive sand in the Hermod Formation; the secondary target was the Eocene Balder Formation Sand. The general objective of well 25/11-19 S was to reduce the range of uncertainty associated with the reserve basis for Balder Mound 6. The well was drilled as a directional well for potential re-entry as a future horizontal producer.
Operations and results
Appraisal well 25/11-19 S was spudded with the semi-submersible installation "Vildkat Explorer" on 24 April 1995 and drilled to TD at 2250 m (2019 m TVD SS) in Triassic (Late Rhaetian) sediments of the Statfjord Formation. The well was drilled with seawater spud mud down to 1015 m and with oil based "Safemul" mud from 1015 m to TD. Shallow gas was neither prognosed nor observed. The well was drilled vertically down to 1032 m before starting to build angle and at top of the primary target, the Hermod sand, the deviation was 38.2deg. at an azimuth of 170.4deg. An 8 1/2" inch hole was drilled to an intermediate depth of 2096 m where an extensive wire line logging program was performed. Then an 8 1/2" hole was drilled to TD of 2250 m and final logging was performed. The 25/11-19 S confirmed oil in the Hermod sand. A good oil water contact was defined by wire line logs, extensive MDT sampling and pressures at 1922.5 m (1760.5 m TVD SS) in the Hermod reservoir sand. Furthermore, gas reserves were proved in the secondary target, the Balder Formation sand, and pressure data indicated a potential GOC at 1839.2 m (1694.8 m TVD SS). Three cores were cut in the Sele and Hermod Formations from 1871 to 1937 m. Wire line fluid samples were taken at 9 different depths using the MDT tool: gas was sampled at 1815.5 m, 1815.6 m, 1816.1 m, and 1834.1 m in the Balder Formation; oil was sampled at 1898 m, 1901.9 m, and 1920 m in the Hermod Formation; and water was sampled at 1182.7 m& in the Skade Formation and at 1961.6 m in the Hermod Formation. The well was plugged below the 13 3/8" casing and temporarily abandoned for possible re-entry as a horizontal oil producer. The well (25/11-19 S R) was re-entered and plugged using the semi-submersible installation "West Alpha" on 1 May 1997. It was permanently abandoned as an oil and gas appraisal well on 6 May 1997.
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