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.
25/11-14 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.
648-L3
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.
74
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,
19.10.1990
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.
31.12.1990
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.
02.12.1991
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.
31.12.1992
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.
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.
DRILLING/TESTING/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
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.
PALEOCENE
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.
HEIMDAL FM
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).
2081.0
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).
1801.3
Maximum inclination [°]
Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.
58
Bottom hole temperature [°C]
Estimated temperature at final total depth of the wellbore. Shown only for released wells.
See discription.
79
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.
HEIMDAL FM
Geodetic datum
Reference system for coordinates. Example of legal values: ED50.
ED50
NS degrees
Geographic coordinate of the wellhead, north-south degrees.
59° 11' 17.31'' N
EW degrees
Geographic coordinate of the wellhead, east-west degrees.
2° 22' 11.64'' E
NS UTM [m]
Universal Transverse Mercator coordinate of the wellhead, north-south.
6561323.70
EW UTM [m]
Universal Transverse Mercator coordinate of the wellhead, east-west.
Well 25/11-14 SR re-entry was drilled centrally on the Balder Field on the Utsira High in the North Sea. This field was discovered in 1967 by the 25/11-1 well, and was the first well on the Norwegian shelf that proved oil. Primary well 25/11-14 S was planned to be completed for a long term test by the FPV Petrojarl 1. The well was planned deviated with kick-off at 1060 m in order to avoid possible shallow gas at 235 m, 254 m, and 515 m. The main objective of this well was to test two Paleocene Heimdal Formation sands; the IB4 sand at 1863 m and the IB3 sand at 1897 m. The Heimdal Formation had previously proved oil-bearing in the three neighbouring wells 25/11-6, -7, and -8. Eocene sands constituted a secondary objective for testing. Based on data from surrounding wells, no abnormal pressure was expected. The surface location and well trajectory for this well, was designed so that a later plug-back and sidetrack to a horizontal completion could be accomplished.
The 25/11-14 SR re-entry was made to fulfil the primary objective of well 25/11-14 S, which was terminated too shallow and without logging and testing due to stuck pipe.
Operations and results
Appraisal well 25/11-14 SR kicked off at 1571 m in 25/11-14 S on 19 October 1990. It was drilled with the semi-submersible installation Byford Dolphin to final TD at 2081 m in sands of the Paleocene Heimdal Formation IB3 sand. After coring the IB3 sand the well was drilled a further 11 m but was TD'ed early as it encountered lost circulation problems between 2077 and 2081 m. It was decided at this point to run casing as quickly as possible to avoid further formation damage prior to the well's main objective of the extended production test. The well was drilled with seawater down to 452 m and with KCl/polymer/gel mud from 452 m to TD.
The secondary target Eocene sands and the upper Heimdal sand IB4 were found missing in the re-entry as it was in the primary well bore. The IB3 sand came in at 1998 m (1753 m TVD RKB). The IB3 sand was oil bearing and the OWC came in as prognosed at 2055 m (1785.3 m TVD / 1760.3 m TVD MSL).
Seven cores were cut in the IB3 sand in the interval 2010 to 2070 m in 25/11-14 SR. These cores proved massive, fine to very fine sandstone of excellent porosity and permeability. Wire line logs were run through casing only due to potential hole problems. No wire line fluid samples were taken in the well bores.
The well was suspended on 31 December 1990 and completed for long term testing. This test was performed with FPV Petrojarl 1 over 146 days during 16 May to 8 October in 1991, classified as test well 25/11-T-14 S. After the test the well bore was again re-entered, this time with the semi-submersible installation Dyvi Stena, and permanently abandoned on 2 December 1991 as an oil appraisal.
Testing
One DST test was performed in the Heimdal Formation IB3 sand in the sidetrack bore hole in two steps, step one without a gravel packer and step two with a gravel packer. The perforated test interval was from 1999.2 m to 2015.2 m. Step one produced 508 Sm3/d through a 13.7 mm choke. Maximum production in step two was 985 Sm3 oil through a 25.4 mm choke. The GOR varied between 36 and 47 Sm3/Sm3, the oil gravity was 23 deg API, and the gas gravity 0.67 (air = 1). No CO2 or H2S was detected. The down-hole temperature recorded in the test, at gauge depth 1986 m (1721 m TVD MSL), was 75.6 deg C. Corrected, stabilized temperature was estimated to be 76.7 deg C.
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