- General information
Wellbore name
7128/4-1
Type
EXPLORATION
Purpose
WILDCAT
Status
P&A
Factmaps in new window
Main area
BARENTS SEA
Discovery
Well name
7128/4-1
Seismic location
ST 9103-417 & SP. 288
Drilled in production licence
Drilling operator
Den norske stats oljeselskap a.s
Drill permit
779-L
Drilling facility
Drilling days
72
Entered date
17.12.1993
Completed date
26.02.1994
Release date
26.02.1996
Publication date
11.04.2003
Purpose - planned
WILDCAT
Reentry
NO
Content
OIL/GAS
Discovery wellbore
YES
1st level with HC, age
LATE PERMIAN
1st level with HC, formation
RØYE FM
Kelly bushing elevation [m]
24.0
Water depth [m]
370.0
Total depth (MD) [m RKB]
2530.0
Final vertical depth (TVD) [m RKB]
2528.1
Maximum inclination [°]
4.8
Bottom hole temperature [°C]
82
Oldest penetrated age
PRE-DEVONIAN
Oldest penetrated formation
BASEMENT
Geodetic datum
ED50
NS degrees
71° 32' 27.33'' N
EW degrees
28° 4' 54.08'' E
NS UTM [m]
7938285.08
EW UTM [m]
538226.27
UTM zone
35
NPDID wellbore
2049
 
 
- Wellbore history
General
Well 7128/4-1 is located in the Finmark Øst area. The main objective for the well was to test the potential for hydrocarbons in Visean sandstone on the "Omd Vest" structure. The secondary objective was to test the hydrocarbon potential, reservoir and trap possibilities of the Asselian - Sakmarian carbonates and the upper Permian succession.
Operations
Exploration well 7128/4-1 was spudded with the semi-submersible installation "Ross Rig" on 17 December 1993 and drilled to TD at 2530 m in pre-Devonian basement rocks, 27 m below base of the Early Carboniferous Soldogg Formation. The well was drilled with seawater and bentonite / CMC EHV spud mud down to 770 m and with GYP/PAC mud from 770 m to TD.
The well penetrated Quaternary, Tertiary, Triassic, Permian, and Carboniferous sediments. The Cretaceous and Jurassic sequences were not present. Gas chromatography readings during drilling and log evaluation indicated gas saturation in the primary target. The sandstone was very tight and therefore not production tested. However, the Late Permian spiculite was partly very porous and permeable with a gas cap over moveable oil. A GOC was indicated at 1575 m.
A total of five conventional cores were cut in the well 1574 m t 1577 m (Late Permian Røye Formation), 1814 m to 1837 m (Isbjørn and Ørn Formations of  Early Permian age), 1837 m to 1865 m (Early Permian Ørn Formation), 2362 m to 2389.47 m (Early Carboniferous Soldogg Formation), and 2526 m to 2530 m (Pre-Devonian basement).
FMT wire line samples were obtained from three levels: 1572.7 m, 1576 m, and 1588.8 m. In the FMT samples taken at 1572.7 m, the 10-litre chamber contained 0.106 m3 of gas with an initial pressure of 8274 kPa. The 4-litre chamber contained 183 litre of gas, 0.5 ml of oil and 1380 ml of water/mud filtrate. Geco measured the density of the gas to 0.637 (air = l). For the samples taken at 1576 m the 10 litre chamber contained 2,5 litre of oil with a density of 0.81 g/cm3, 0.190 m3 of gas and the total liquid (mud filtrate + oil) volume was 9.3 litre. The 4 litre chamber contained 63.5 litre of gas, 225 ml of oil and the water volume was not possible to measure due to water leakage past the piston when the Geco transferred from FMT bottle to a PVT bottle. The gas gravity was measured to 0.790 (air = l). The oil density of stabilized oil was measured to 0.817 g/cm3 at 15 °C. One 10-litre sample taken at 1588.8 m contained 2.5 litre of mud filtrate. The sampling aborted after 4 hrs and 17 min. The well was permanently abandoned on 26 February 1994 as an oil and gas discovery.
Testing
Two zones were perforated and tested: Test no. 1 from 1592 -1610 m, and test no. 2 from 1577 -1586 m. For test no. 1 both diesel and Nitrogen was used to increase the under-balance, but the well did not flow. Finally, after stimulation with HCl test no. 1 produced 320 000 Sm3/d gas, 17 m3/d oil, and 70 m3/d water on a 72 mm choke. The HCl stimulation may have affected the cement, and the producing interval was probably the porous spiculite at 1569 m to 1590 m. Test no. 2 produced 215 000 Sm3/d gas, 15 m3/d oil, and 85 m3/d water on a 25.4 mm choke.
l>
 
 
- Cuttings at the NPD
Cutting sample, top depth [m]
Cutting samples, bottom depth [m]
780.00
2529.00
Cuttings available for sampling?
YES
 
 
- Cores at the NPD
Core sample number
Core sample - top depth
Core sample - bottom depth
Core sample depth - uom
1
1574.0
1576.3
[m ]
2
1814.0
1836.0
[m ]
3
1837.0
1865.7
[m ]
4
2362.0
2389.5
[m ]
5
2526.0
2528.5
[m ]
Total core sample length [m]
82.9
Cores available for sampling?
YES
 
 
- Core photos
Click to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the picture
1574-1576m
1814-1818m
1818-1822m
1822-1826m
1826-1830m
     
Click to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the picture
1830-1834m
1834-1836m
1837-1841m
1841-1845m
1845-1849m
     
Click to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the picture
1849-1853m
1853-1857m
1857-1861m
1861-1865m
1865-1866m
     
Click to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the picture
2362-2366m
2362-2466m
2366-2370m
2366-2470m
2370-2374m
     
Click to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the picture
2370-2474m
2374-2378m
2374-2478m
2378-2382m
2378-2482m
     
Click to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the pictureClick to enlarge the picture
2382-2386m
2382-2486m
2386-2390m
2386-2489m
2526-2529m
     
 
 
- Palynological slides at the NPD
Sample depth
Depth unit
Sample type
Laboratory
892.0
[m]
SWC
STATO
925.0
[m]
SWC
STATO
981.0
[m]
SWC
STATO
1055.0
[m]
SWC
STATO
1281.0
[m]
SWC
STATO
1323.5
[m]
SWC
STATO
1339.0
[m]
SWC
STATO
1399.0
[m]
SWC
STATO
1514.5
[m]
SWC
STATO
1538.0
[m]
SWC
STATO
1543.0
[m]
SWC
STATO
1555.0
[m]
SWC
STATO
1561.0
[m]
SWC
STATO
1566.0
[m]
SWC
STATO
1568.5
[m]
SWC
STATO
1668.0
[m]
SWC
STATO
1682.5
[m]
SWC
STATO
1693.0
[m]
SWC
STATO
1701.5
[m]
SWC
STATO
1814.7
[m]
C
STATO
1819.6
[m]
C
STATO
1824.9
[m]
C
STATO
1828.2
[m]
C
STATO
1851.5
[m]
C
STATO
2009.0
[m]
SWC
STATO
2015.3
[m]
SWC
STATO
2057.0
[m]
SWC
STATO
2091.0
[m]
SWC
STATO
2103.0
[m]
SWC
STATO
2130.8
[m]
SWC
STATO
2170.0
[m]
SWC
STATO
2182.0
[m]
SWC
STATO
2211.0
[m]
SWC
STATO
2243.5
[m]
SWC
STATO
2257.0
[m]
SWC
STATO
2282.0
[m]
SWC
STATO
2286.0
[m]
SWC
STATO
2311.0
[m]
SWC
STATO
2331.5
[m]
SWC
STATO
2342.0
[m]
SWC
STATO
2363.7
[m]
C
STATO
2368.9
[m]
C
STATO
2375.3
[m]
C
STATO
2381.6
[m]
C
STATO
2389.5
[m]
C
STATO
2396.0
[m]
SWC
STATO
2450.0
[m]
SWC
STATO
 
 
- Oil samples at the NPD
Test type
Bottle number
Top depth
MD [m]
Bottom depth
MD [m]
Fluid type
Test time
Samples available
DST
DST1-1A
1610.00
1595.00
09.02.1994 - 00:00
YES
DST
DST1A-1B
1610.00
1577.00
10.02.1994 - 21:00
YES
DST
DST2
1577.00
0.00
17.02.1994 - 14:15
YES
 
 
- Lithostratigraphy
 
 
- Composite logs
Document name
Document format
Document size [KB]
pdf
0.39
 
 
- Geochemical information
Document name
Document format
Document size [KB]
pdf
1.84
pdf
1.03
pdf
1.91
pdf
5.05
 
 
- Documents - reported by the production licence (period for duty of secrecy expired)
Document name
Document format
Document size [KB]
pdf
51.84
 
 
- Drill stem tests (DST)
Test number
From depth MD
[m]
To depth MD
[m]
Choke size
[mm]
1.0
1592
1610
72.0
2.0
1577
1586
25.4
Test number
Final shut-in pressure
[MPa]
Final flow pressure
[MPa]
Bottom hole pressure
[MPa]
Downhole temperature
[°C]
1.0
    
2.0
 
30.000
  
Test number
Oil
[Sm3/day]
Gas
[Sm3/day]
Oil density
[g/cm3]
Gas grav. rel.air
GOR
[m3/m3]
1.0
17
320000
  
18823
2.0
15
215000
0.797
0.638
14333
 
 
- Logs
Log type
Log top depth [m]
Log bottom depth [m]
CBIL GR
1502
2469
CBL VDL GR
1100
1502
DIFL ACL ZDL CNL GR
1502
2023
DIFL ACL ZDL GR
750
1517
DIFL ACL ZDL GR
2432
2530
DIFL MAC SL GR
1502
2471
DLL MLL GR
1540
1718
FMT
1570
1594
FMT GR
1573
1574
FMT GR
1576
1576
FMT GR
1585
1589
FMT GR
1594
2447
FMT GR
1594
2420
FMT GR
1658
1685
MWD
460
2526
SHDT GR
1503
2463
SWC GR
756
1515
SWC GR
1533
1691
SWC GR
1693
2072
SWC GR
2076
2467
VSP GR
493
2460
ZDL CNL GR
1988
2469
 
 
- Casing and leak-off tests
Casing type
Casing diam.
[inch]
Casing depth
[m]
Hole diam.
[inch]
Hole depth
[m]
LOT mud eqv.
[g/cm3]
Formation test type
CONDUCTOR
30
455.0
36
455.0
0.00
LOT
INTERM.
20
750.0
26
750.0
1.40
LOT
INTERM.
13 3/8
1502.0
17 1/2
1504.0
1.74
LOT
INTERM.
9 5/8
2432.0
12 1/4
2432.0
1.50
LOT
OPEN HOLE
2530.0
8 1/2
2530.0
0.00
LOT
OPEN HOLE
2530.0
8 1/2
0.0
0.00
LOT
 
 
 
- Drilling mud
Depth MD [m]
Mud weight [g/cm3]
Visc. [mPa.s]
Yield point [Pa]
Mud type
Date measured
715
1.20
15.0
 
WATER BASED
 
770
1.12
17.0
 
WATER BASED
 
815
1.03
17.0
 
WATER BASED
 
1307
1.20
18.0
 
WATER BASED
 
1495
1.20
15.0
 
WATER BASED
 
1525
1.20
18.0
 
WATER BASED
 
1589
1.12
  
WATER BASED
 
1701
1.20
19.0
 
WATER BASED
 
1814
1.20
19.0
 
WATER BASED
 
1951
1.20
21.0
 
WATER BASED
 
2092
1.20
23.0
 
WATER BASED
 
2141
1.20
26.0
 
WATER BASED
 
2356
1.20
26.0
 
WATER BASED
 
2468
1.10
9.0
 
WATER BASED
 
2523
1.10
17.0
 
WATER BASED
 
2530
1.12
  
WATER BASED