Wellbore: 30/5-2 - Factpages - Norwegian Offshore Directorate

General information

General information
Attribute	Value
Wellbore name Official name of wellbore based on Norwegian Offshore Directorate guidelines for designation of wells and wellbores.	30/5-2
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.	P&A
Factmaps in new window	link to map
Main area Name of the area on the Norwegian Continental Shelf where the wellbore is located. Legal values: BARENTS SEA, NORWEGIAN SEA, NORTH SEA.	NORTH SEA
Field Name of the field the wellbore is related to.	TUNE
Discovery Name of the discovery the wellbore is related to.	30/8-1 S Tune
Well name Official name of the parent well for the wellbore based on Norwegian Offshore Directorate guidelines for designation of wells and wellbores.	30/5-2
Seismic location Position of spud location on seismic survey lines. SP: shotpoint.	SH 9106- INLINE 445 & CROSSLINE 177
Production licence Official designation of the production licence the wellbore was drilled or planned to be drilled from ( well head posistion).	034
Drilling operator 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.	Norsk Hydro Produksjon AS
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.	861-L
Drilling facility Norwegian Offshore Directorate's name of the facility which the wellbore was drilled from.	TREASURE SAGA
Drilling days Number of days from wellbore entry to wellbore completion.	79
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,	04.10.1996
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.	21.12.1996
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.	21.12.1998
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.	18.12.2008
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.	NO
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/GAS
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.	MIDDLE JURASSIC
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.	BRENT GP
Kelly bushing elevation [m] Elevation of the rotary kelly bushing (RKB) above mean sea level.	26.0
Water depth [m] Depth in metres betweem mean sea level and sea floor.	92.0
Total depth (MD) [m RKB] Total measured length of wellbore from kelly bushing to total depth (driller's depth).	4076.0
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).	4075.0
Maximum inclination [°] Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.	3
Bottom hole temperature [°C] Estimated temperature at final total depth of the wellbore. Shown only for released wells. See discription.	139
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.	EARLY JURASSIC
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.	DRAKE FM
Geodetic datum Reference system for coordinates. Example of legal values: ED50.	ED50
NS degrees Geographic coordinate of the wellhead, north-south degrees.	60° 30' 16.3'' N
EW degrees Geographic coordinate of the wellhead, east-west degrees.	2° 38' 12.71'' E
NS UTM [m] Universal Transverse Mercator coordinate of the wellhead, north-south.	6707814.40
EW UTM [m] Universal Transverse Mercator coordinate of the wellhead, east-west.	480053.38
UTM zone Universal Transverse Mercator zone. Examples of legal values: 31, 32, 33, 34.	31
NPDID wellbore Norwegian Offshore Directorate's unique id for the wellbore.	2886

Well 30/5-2 is located a few km west of the Oseberg Field in the Northern North Sea. It was drilled on the northern and down dip extension of the hydrocarbon accumulation discovered by well 30/8-1 S. The main target was the Brent deltaic sands of the Tarbert Formations. The primary objectives were to prove filling level and hydrocarbon types in a down dip (northern) direction, and to prove pressure communication and continuity with the reservoirs in 30/8-1 S. Planned TD was 50 m into the Dunlin Group.

Operations and results

Appraisal well 30/5-2 was spudded with the semi-submersible installation Treasure Saga on 4 October 1996 and drilled to TD at 4076 m in the Early Jurassic Drake Formation. The total duration of the well was some 20 days behind schedule. The main contribution to this was time spent to cure a shallow gas source, corrective measures in conjunction with a 13 3/8" casing hanger sitting high and a stuck MDT tool. The well was drilled with spud mud and bentonite down to 1558 m, with KCl/polymer mud from 1558 m to TD.

The main reservoir interval consisted of the Tarbert Formation, but the Ness and ORE Formations were also encountered. Gas and oil pay was interpreted below 3528.5 m in the "Tarbert 2" reservoir, approximately 58 m and 10 m respectively. The well interpretation concludes with a GDT (gas down to) situation at 3591.5 m in the Tarbert 2 reservoir and with an OUT (oil up to) at 3602 m. An OWC is indicated at 3614 m with a FWL (free water level) at about 3616.5 m. In the Ness Formation a total of 16 m pay was interpreted in channel sands. The assumed fluid in these sands is gas, but this was not conclusively proven. The ORE (Oseberg - Rannoch - Etive) Formation had 1.4 m pay interpreted, but this may be an optimistic result as it was equally likely that this could represent so-called residual hydrocarbons. The reservoir properties are considered fairly modest with porosities generally below 20 % and with core permeabilities generally in the range 1 to 100 mD. The best properties, based on MDT mobility, were found in the Tarbert 2 gas reservoir and in the water bearing Ness sand at 3720 - 3740 m.

Three cores were cut in the Tarbert Formation from 3531 to 3632.35 m.

The well was permanently abandoned on 21 December 1996 as an oil and gas appraisal well.

Testing

Three drill stem tests were performed. DST IA tested the water zone in the interval 3623.3 - 3627.8 m. It produced water at a rate of 30 m3 /day. DST IB tested the intervals 3623.3 - 3627.8 m + 3601.3 - 3621.3 m. In the main flow, using a 32/64" choke, it produced 250 m3 water, 135 Sm3 oil, and 63000 Sm3 gas /day. The GOR was 470 Sm3/Sm3, the oil density was 0.88 g/cm3 and the gas gravity was 0.79 - 0.82 (air = 1). The initial reservoir temperature measured in this flow was 131.1 deg C. DST II tested the gas zone in the interval 3529.1 - 3591.1 m. At maximum rates in the main flow, using a 72/64" choke, this test produced 980000 Sm3 gas and 510 Sm3 oil /day. No water was produced. The GOR was 1920 Sm3/Sm3, the oil density was 0.83 g/cm3, and the gas gravity was 0.69 (air = 1). The initial reservoir temperature measured in this flow was 127.4 deg C.

Cuttings at the Norwegian Offshore Directorate

Cuttings at the Norwegian Offshore Directorate
Cuttings available for sampling?	YES

Cuttings at the Norwegian Offshore Directorate
Cutting sample, top depth [m]	Cutting samples, bottom depth [m]
350.00	4075.00

Cores at the Norwegian Offshore Directorate

Cores at the Norwegian Offshore Directorate
Core sample number	Core sample - top depth	Core sample - bottom depth	Core sample depth - uom
1	3531.0	3558.3	[m ]
2	3558.5	3595.4	[m ]
3	3595.5	3632.4	[m ]

Cores at the Norwegian Offshore Directorate
Total core sample length [m]	101.0

Cores at the Norwegian Offshore Directorate
Cores available for sampling?	YES

Core photos

Core photos

3531-3536m	3536-3541m	3541-3546m	3546-3551m	3551-3556m

3556-3558m	3558-3563m	3563-3568m	3568-3573m	3573-3578m

3578-3583m	3583-3588m	3588-3593m	3593-3595m	3595-3600m

3600-3605m	3605-3610m	3610-3615m	3615-3620m	3620-3625m

3625-3620m	3630-3632m

Oil samples at the Norwegian Offshore Directorate

Oil samples at the Norwegian Offshore Directorate
Test type	Bottle number	Top depth MD [m]	Bottom depth MD [m]	Fluid type	Test time	Samples available
DST	DST1B	3601.30	3627.80		04.12.1996 - 04:00	YES
DST	DST2	3529.00	3591.00		10.12.1996 - 22:12	YES

Lithostratigraphy

Lithostratigraphy
Top depth [mMD RKB]	Lithostrat. unit
118	NORDLAND GP
680	UTSIRA FM
760	UNDIFFERENTIATED
917	HORDALAND GP
993	SKADE FM
1045	NO FORMAL NAME
1487	GRID FM
1632	NO FORMAL NAME
2091	ROGALAND GP
2091	BALDER FM
2169	SELE FM
2271	LISTA FM
2430	VÅLE FM
2449	SHETLAND GP
2449	HARDRÅDE FM
2470	JORSALFARE FM
2702	KYRRE FM
3167	TRYGGVASON FM
3288	BLODØKS FM
3292	SVARTE FM
3468	VIKING GP
3468	HEATHER FM
3472	BRENT GP
3472	TARBERT FM
3710	NESS FM
4005	UNDIFFERENTIATED
4041	DUNLIN GP
4041	DRAKE FM

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 name	Document format	Document size [MB]
2886_30_5_2_COMPLETION_REPORT_AND_COMPLETION_LOG	pdf	17.61

Drill stem tests (DST)

Drill stem tests (DST)
Test number	From depth MD [m]	To depth MD [m]	Choke size [mm]
1.0	3611	3624	12.5
2.0	3566	3590	11.0

Drill stem tests (DST)
Test number	Final shut-in pressure [MPa]	Final flow pressure [MPa]	Bottom hole pressure [MPa]	Downhole temperature [°C]
1.0	7.000		24.000	130
2.0	36.000			127

Drill stem tests (DST)
Test number	Oil [Sm3/day]	Gas [Sm3/day]	Oil density [g/cm3]	Gas grav. rel.air	GOR [m3/m3]
1.0	135	63000	0.880	0.710	470
2.0	140	300000	0.830	0.690	2140

Logs

Logs
Log type	Log top depth [m]	Log bottom depth [m]
DLL MSFL DSI GR SP ACTS	3676	4075
FMI GR ACTS	3476	4063
LDL CNL CMR NGT ACTS	3476	4075
MDT GR ACTS	3529	3766
MDT GR AMS	3566	3621
MRIL GR	3510	3660
MWD - GR RES DIR	118	4076
VSP GR	3000	4010

Casing and leak–off tests

Casing and leak–off tests
Casing type	Casing diam. [inch]	Casing depth [m]	Hole diam. [inch]	Hole depth [m]	Formation test type
CONDUCTOR	30	190.0	36	192.0	LOT
SURF.COND.	13 3/8	1544.0	17 1/2	1558.0	LOT
INTERM.	9 5/8	3476.0	12 1/4	3477.0	LOT
LINER	7	4070.0	8 1/2	4076.0	LOT

Drilling mud

Drilling mud
Depth MD [m]	Mud weight [g/cm3]	Visc. [mPa.s]	Mud type
150	1.14		WATER BASED
250	1.20		WATER BASED
263	1.64	40.0	WATER BASED
300	1.20	11.0	WATER BASED
1558	1.20	18.0	WATER BASED
2513	1.41	24.0	WATER BASED
3478	1.41	23.0	WATER BASED
3828	1.64	34.0	WATER BASED
4076	1.64	39.0	WATER BASED
4078	1.64	37.0	WATER BASED

Pressure plots

Pressure plots
The pore pressure data is sourced from well logs if no other source is specified. In some wells where pore pressure logs do not exist, information from Drill stem tests and kicks have been used. The data has been reported to the NPD, and further processed and quality controlled by IHS Markit.

Pressure plots
Document name	Document format	Document size [MB]
2886_Formation_pressure_(Formasjonstrykk)	pdf	0.23

30/5-2