2/7-5
Export: PDF
-
General information
-
Wellbore history
GeneralWell 2/7-5 was drilled ca 4.5 km north-northeast of the 2/7-4 well, which found oil in the Ekofisk and Tor Formations, the Edda Discovery. The objective of the 2/7-5 well was to test the Ekofisk and Tor Formations in order to appraise the extension of this discovery.Operations and resultsAppraisal well 2/7-5 was spudded with the semi-submersible installation Ocean Viking on 3 September 1972 and drilled to TD at 3353 m in the Late Cretaceous Tor Formation. The well was drilled water based with 3 - 6 % oil addition below 1217 m.The Ekofisk Formation was encountered at 3110 m, and the Tor Formation at 3205 m. Both formations appeared to be hydrocarbon bearing, but the water saturation was high and the permeability was generally low, which probably explained the low flow rates of the zones tested.Eight conventional cores were cut in the interval 3120 - 3158 m in the Ekofisk Formation, and another five cores were cut in the interval 3219 - 3300 m in the Tor Formation. The cores were reported to bleed gas and oil. Scattered shows (fluorescence) were observed from top of the cored interval and down to 3285 m in the deepest core (core 13). No wire line fluid samples were taken.The well was permanently abandoned on 1 January 1973 as a dry well with shows.TestingSeveral drill stem tests were conducted in the limestone and chalk of the Ekofisk and Tor Formations. Many were unsuccessful. Of the technically successful tests DST 1 from 3274 m to 3293 m and DST 2 from 3225 - 3237 m flowed water. DST 3 from 3210 - 3219 m flowed water with gas and trace of oil. DST 4 from 3160 - 3185 m and DST 5 from 3120 - 3130 m flowed minor amounts of gas and water. -
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]1525.003352.80 -
Cores at the Norwegian Offshore Directorate
Cores at the Norwegian Offshore Directorate Core sample numberCore sample - top depthCore sample - bottom depthCore sample depth - uom110237.010293.0[ft ]210293.010350.0[ft ]310350.010367.0[ft ]410367.010417.0[ft ]510417.010431.5[ft ]610431.510490.0[ft ]710490.010504.0[ft ]810504.010562.0[ft ]910562.010570.0[ft ]1010619.010655.0[ft ]1110658.010713.0[ft ]1210714.010771.0[ft ]1310772.010822.0[ft ]Cores at the Norwegian Offshore Directorate Total core sample length [m]161.8Cores at the Norwegian Offshore Directorate Cores available for sampling?YES -
Lithostratigraphy
Lithostratigraphy Top depth [mMD RKB]Lithostrat. unit99174829682968298030333087311031103205 -
Composite logs
Composite logs Document nameDocument formatDocument size [MB]pdf0.32 -
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]pdf1.19pdf19.56 -
Drill stem tests (DST)
Drill stem tests (DST) Test numberFrom depth MD
[m]To depth MD
[m]Choke size
[mm]1.0327432930.02.0322532370.03.0321032190.04.0316031850.05.0312032300.0Drill stem tests (DST) Test numberFinal shut-in pressure
[MPa]Final flow pressure
[MPa]Bottom hole pressure
[MPa]Downhole temperature
[°C]1.02.03.04.05.0Drill stem tests (DST) Test numberOil
[Sm3/day]Gas
[Sm3/day]Oil density
[g/cm3]Gas grav. rel.airGOR
[m3/m3]1.02.03.04.05.0 -
Logs
Logs Log typeLog top depth [m]Log bottom depth [m]BHC4811230BHC C12162441BHC C24323349CBL23593301CDM AP PP24323352CNL30023305DL29573349FDC CNL24323352GR91481IES4813352PML30483352VELOCITY4813349 -
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 typeCONDUCTOR30134.036136.00.00LOTSURF.COND.20480.026494.00.00LOTINTERM.13 3/81217.017 1/21217.00.00LOTINTERM.9 5/82433.012 1/42443.00.00LOTINTERM.73349.08 1/23353.00.00LOT -
Drilling mud
Drilling mud Depth MD [m]Mud weight [g/cm3]Visc. [mPa.s]Yield point [Pa]Mud typeDate measured1211.08seawater4881.31seawater12191.4345.0waterbased24381.71waterbased33531.7350.0waterbased