- General information
Wellbore name
25/11-24
Type
EXPLORATION
Purpose
WILDCAT
Status
P&A
Press release
Factmaps in new window
Main area
NORTH SEA
Discovery
Well name
25/11-24
Seismic location
3D survey (NH9301):inline 1691 & crossline 2462
Drilled in production licence
Drilling operator
Norsk Hydro Petroleum AS
Drill permit
1131-L
Drilling facility
Drilling days
40
Entered date
18.02.2007
Completed date
29.03.2007
Release date
29.03.2009
Publication date
29.03.2009
Purpose - planned
WILDCAT
Reentry
NO
Content
OIL
Discovery wellbore
YES
1st level with HC, age
PALEOCENE
1st level with HC, formation
HEIMDAL FM
2nd level with HC, age
JURASSIC
2nd level with HC, formation
STATFJORD GP
Kelly bushing elevation [m]
26.0
Water depth [m]
114.0
Total depth (MD) [m RKB]
2117.0
Final vertical depth (TVD) [m RKB]
2117.0
Maximum inclination [°]
1.2
Bottom hole temperature [°C]
81
Oldest penetrated age
EARLY JURASSIC
Oldest penetrated formation
STATFJORD GP
Geodetic datum
ED50
NS degrees
59° 6' 12.68'' N
EW degrees
2° 20' 27.73'' E
NS UTM [m]
6551916.90
EW UTM [m]
462253.22
UTM zone
31
NPDID wellbore
5470
 
 
- Wellbore history
General
Exploration well 25/11-24 was drilled to test the Midway prospect in PL 169 and PL 028C. Midway is located south of Balder and south west of the Grane field. The main reservoir target of the well was the Heimdal sand mound, located close to the eastern pinch-out of a Tertiary submarine fan system on the western margin of the Utsira High. The primary objective was to prove commercial hydrocarbon resources within the Lista, Sele and/or Balder formations and to establish the oil-water contact. The well was located within a closure at top Jurassic level, and a secondary objective was to test the Statfjord Formation.
Operations and results
Well 25/11-24 was spudded with the semi-submersible installation Transocean Winner on 18 February 2007 and drilled to TD at 2117 m in Early Jurassic sediments of the Statfjord Formation. No significant technical problems were encountered in the operations. The well was drilled with sea water down to 1106 m and with a polymer/KCl/glycol mud from 1106 m to TD.
The Rogaland Group was encountered at 1718 m. A thick Heimdal sand with excellent reservoir properties was encountered at 1788 m. It had had an insignificant (1-2 metres) oil column at the top, but was otherwise water-filled. The Heimdal sand is depleted, probably due to production from surrounding fields. Insignificant amounts of injection and/or deposited sands were observed above the main Heimdal sand (in Balder/Sele/Lista). The injections sands had oil shows and were interpreted as oil bearing. The injection sand in Balder was not in pressure communication with the Heimdal sand. In top of the Statfjord formation, a 4 meter oil column was encountered. The oil was light (0.726 g/cc) and the reservoir properties were good. Below the good oil zone the reservoir was highly laminated. The pressure analysis showed a situation with oil-down-to at 2033 m and water-up to at 2048.5 m, where the oil and the water were not in communication.
No conventional cores were taken. A complex MDT tool string for combined formation pressure measurements, fluid sampling/scanning and minitest/VIT was run. Forty-three pretests were attempted, of which 31 were regarded as good, 7 were dry and 5 lost seal. At 2029.5 m in the Statfjord Formation, four good fluid samples (1x 2 3/4 gal sample chamber and 3x450cc bottles) were taken. Fluid sampling in the Heimdal Formation was abandoned due to bad weather.
The well was permanently abandoned on 29 March 2007 as an oil discovery.
Testing
No drill stem test was performed.
 
 
- Cuttings at the NPD
Cutting sample, top depth [m]
Cutting samples, bottom depth [m]
1110.00
2117.20
Cuttings available for sampling?
YES
 
 
- Palynological slides at the NPD
Sample depth
Depth unit
Sample type
Laboratory
1210.0
[m]
DC
HYDRO
1230.0
[m]
DC
HYDRO
1250.0
[m]
DC
HYDRO
1270.0
[m]
DC
HYDRO
1290.0
[m]
DC
HYDRO
1310.0
[m]
DC
HYDRO
1330.0
[m]
DC
HYDRO
1350.0
[m]
DC
HYDRO
1370.0
[m]
DC
HYDRO
1390.0
[m]
DC
HYDRO
1410.0
[m]
DC
HYDRO
1430.0
[m]
DC
HYDRO
1450.0
[m]
DC
HYDRO
1471.0
[m]
DC
HYDRO
1490.0
[m]
DC
HYDRO
1510.0
[m]
DC
HYDRO
1530.0
[m]
DC
HYDRO
1551.0
[m]
DC
HYDRO
1570.0
[m]
DC
HYDRO
1590.0
[m]
DC
HYDRO
1610.0
[m]
DC
HYDRO
1630.0
[m]
DC
HYDRO
1650.0
[m]
DC
HYDRO
1662.0
[m]
DC
HYDRO
1674.0
[m]
DC
HYDRO
1686.0
[m]
DC
HYDRO
1695.0
[m]
DC
HYDRO
1704.0
[m]
DC
HYDRO
1710.0
[m]
DC
HYDRO
1719.0
[m]
DC
HYDRO
1728.0
[m]
DC
HYDRO
1740.0
[m]
DC
HYDRO
1749.0
[m]
DC
HYDRO
1758.0
[m]
DC
HYDRO
1767.0
[m]
DC
HYDRO
1776.0
[m]
DC
HYDRO
1785.0
[m]
DC
HYDRO
1797.0
[m]
DC
HYDRO
1809.0
[m]
DC
HYDRO
1821.0
[m]
DC
HYDRO
1833.0
[m]
DC
HYDRO
1845.0
[m]
DC
HYDRO
1869.0
[m]
DC
HYDRO
1884.0
[m]
DC
HYDRO
1890.0
[m]
DC
HYDRO
1905.0
[m]
DC
HYDRO
1926.0
[m]
DC
HYDRO
1938.0
[m]
DC
HYDRO
1944.0
[m]
DC
HYDRO
1956.0
[m]
DC
HYDRO
1962.0
[m]
DC
HYDRO
2001.0
[m]
DC
HYDRO
2007.0
[m]
DC
HYDRO
2013.0
[m]
DC
HYDRO
2022.0
[m]
DC
HYDRO
2024.0
[m]
SWC
HYDRO
2029.0
[m]
SWC
HYDRO
2029.1
[m]
SWC
HYDRO
2031.0
[m]
DC
HYDRO
2034.0
[m]
DC
HYDRO
2037.0
[m]
DC
HYDRO
2038.5
[m]
SWC
HYDRO
2044.8
[m]
SWC
HYDRO
2047.0
[m]
SWC
HYDRO
2060.0
[m]
SWC
HYDRO
2062.0
[m]
SWC
HYDRO
2073.0
[m]
DC
HYDRO
2082.0
[m]
DC
HYDRO
2091.0
[m]
DC
HYDRO
2097.0
[m]
DC
HYDRO
2103.5
[m]
SWC
HYDRO
2109.0
[m]
DC
HYDRO
2117.2
[m]
DC
HYDRO
 
 
- Lithostratigraphy
 
 
- Composite logs
Document name
Document format
Document size [KB]
pdf
0.36
 
 
- Geochemical information
Document name
Document format
Document size [KB]
txt
0.00
txt
0.07
pdf
0.09
pdf
2.69
 
 
- Logs
Log type
Log top depth [m]
Log bottom depth [m]
CMR GR
1650
2110
MDT GR
1722
2103
MSCT GR
1888
2024
MSCT GR
2027
2103
MWD LWD - DIR
140
225
MWD LWD - DIR
225
1110
MWD LWD - DIR GR RES
225
880
MWD LWD - DIR GR RES
1110
2117
PEX HRLA ECS
760
1642
PEX HRLA SP ECS CMR
1523
2057
SON SCANNER FMI GR
295
1643
 
 
- 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
219.0
36
219.0
0.00
LOT
SURF.COND.
20
1101.0
26
1106.0
1.55
LOT
INTERM.
9 5/8
1642.0
12 1/4
1650.0
1.70
LOT
OPEN HOLE
2117.0
8 1/2
2117.0
0.00
LOT
 
 
 
- Drilling mud
Depth MD [m]
Mud weight [g/cm3]
Visc. [mPa.s]
Yield point [Pa]
Mud type
Date measured
1106
1.29
24.0
 
WATER BASED
 
1196
1.29
26.0
 
WATER BASED
 
1650
1.35
33.0
 
WATER BASED
 
1650
1.35
32.0
 
WATER BASED
 
1819
1.22
32.0
 
WATER BASED
 
2003
1.22
31.0
 
WATER BASED
 
2117
1.22
31.0
 
WATER BASED
 
2117
1.35
28.0
 
WATER BASED