25/2-14
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General information
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Wellbore history
GeneralWell 25/2-14 was drilled to appraise the Jurassic C prospect on the Frøy Field in the central Viking Graben. The northern part of the Frøy Field appears as a triangle delineated by 3 faults slightly tilted to the WNW, where the eastern limit is the main fault bordering the Frøy structure with a 300 m down-throw, and the northern border is another major fault. It is the western fault trending NNW-SSE, that separates the northern C compartment from the rest of the field, and well 25/2-14 is located in a down flank position. The location was chosen so as not to come too close to the eastern border fault, to leave a limited up dip if any, and to get a full Vestland sequence with the assumed oil water contact within the upper part of the section.The main objective of the well was to explore the Middle Jurassic sandstones, which are the main reservoir in the Frøy Field. The Lower Jurassic Statfjord sandstones was a secondary target, depending on the results at Vestland level.Boulders had been observed at 38 and 40 below seabed within 70 metres off location, and a strong reflector at 300 m indicated shallow gas. A hydrostatic regime was expected in throughout the reservoir except for Statfjord, which could be slightly over pressured.Operations and resultsAppraisal well 25/2-14 was spudded with the semi-submersible rig West Vanguard 25 January 1991 and drilled to TD at 3623 m in the Early Jurassic Statfjord Formation. Minor problems were encountered while drilling 8 1/2" pilot hole down to 473 m. Top Vestland Group (Hugin Formation) was as found at the forecasted depth at 3135 m. Top Statfjord Formation was found at 3520.5 m (expected depth was 3537 m). Both reservoirs were found water-wet. There was a general lack of shows throughout the well, the only show was recorded on a 1 m section of core no 4 around 3157 m. Geochemical analyses confirmed a dry well all through. FMT pressure data indicated a separate pressure regime from the Frøy Field. Fifty sidewall cores were attempted and 48 were recovered. Four cores were cut, two in Hordaland shales from 2010 m to 2015 m, and two from the base of the Heather Formation and into the top of the Vestland Group from 3130 m to 3168 m. The well was permanently abandoned on 30 March 1991 as a dry well.TestingNo drill stem test was performed -
Cuttings at the Norwegian Offshore Directorate
Cuttings at the Norwegian Offshore Directorate Cuttings available for sampling?YESCuttings at the Norwegian Offshore Directorate Cutting sample, top depth [m]Cutting samples, bottom depth [m]210.003623.00 -
Cores at the Norwegian Offshore Directorate
Cores at the Norwegian Offshore Directorate Core sample numberCore sample - top depthCore sample - bottom depthCore sample depth - uom33130.03149.0[m ]43149.03167.8[m ]Cores at the Norwegian Offshore Directorate Total core sample length [m]37.8Cores at the Norwegian Offshore Directorate Cores available for sampling?YES -
Core photos
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Casing and leak–off tests
Casing and leak–off tests Casing typeCasing diam.
[inch]Casing depth
[m]Hole diam.
[inch]Hole depth
[m]LOT/FIT mud eqv.
[g/cm3]Formation test typeCONDUCTOR30202.036205.00.00LOTINTERM.13 3/81199.017 1/21201.01.83LOTINTERM.9 5/83055.012 1/43057.01.71LOTOPEN HOLE3623.08 1/23623.00.00LOT -
Logs
Logs Log typeLog top depth [m]Log bottom depth [m]ACBL VDL GR19003054CDL CNC GR CAL30253624CORGUN20822688CORGUN 2530593584DIFL AC GR SP11983075DIFL AC GR SP30253624DIPLOG11983075DIPLOG30553624FMT HP31373574MWD - GR RES DIR1413623SP36233625VSP5703600ZDL GR CAL11983075 -
Lithostratigraphy
Lithostratigraphy Top depth [mMD RKB]Lithostrat. unit13950555467367310741348142521642164221122422259230423312482255225522844297030293029306031353135315633223521 -
Composite logs
Composite logs Document nameDocument formatDocument size [MB]pdf0.50 -
Geochemical information
Geochemical information Document nameDocument formatDocument size [MB]pdf0.51 -
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 nameDocument formatDocument size [MB]PDF56.83 -
Drilling mud
Drilling mud Depth MD [m]Mud weight [g/cm3]Visc. [mPa.s]Yield point [Pa]Mud typeDate measured3681.03WATER BASED29.01.199112131.0910.015.6WATER BASED04.02.199128481.3531.019.6WATER BASED04.03.199128741.3532.020.5WATER BASED04.03.199129341.3527.038.0WATER BASED06.03.199130721.3522.017.6WATER BASED08.03.199134961.25202.089.1WATER BASED19.03.199136231.2625.010.2WATER BASED21.03.1991 -
Palynological slides at the Norwegian Offshore Directorate
Palynological slides at the Norwegian Offshore Directorate Sample depthDepth unitSample typeLaboratory3130.0[m]CAPT3130.9[m]CAPT3131.7[m]CAPT3132.3[m]CAPT3132.8[m]CAPT3133.4[m]CAPT3134.3[m]CAPT3134.6[m]CAPT3135.0[m]CAPT3135.1[m]CAPT3135.3[m]CAPT3135.5[m]CAPT3136.6[m]CAPT3138.3[m]CAPT3140.3[m]CAPT3140.8[m]CAPT3142.9[m]CAPT3143.8[m]CAPT3145.3[m]CAPT