OD 1304015
Age(Ma)
Pleistoc.
Epoch Viking Graben Frigg AreaCentral Graben/Norwe-
gian Danish Basin
NO
RDLA
ND
GRO
UP
HO
RDA
LAN
D G
ROU
P
Viking GrabenGr.58°56°30’
57°
S62°N
Pliocene
LateMiocene
MiddleMiocene
EarlyMiocene
LateOligocene
EarlyOligocene
Eocene/Hiatus
Utsira Fm
Skade Fm
Hiatus
UnnamedVade Fm
Utsira FmGlauconiticUtsira Fm
(5,7-4,2 Ma)
5
10
15
20
25
3029,2-30,3 Ma
26-26,3 Ma
27,2-26,4 Ma
32,7-31,5 Ma
27,2-25,7 Ma
24-23,9 Ma
15,9-15,5 Ma
19-16,4 Ma
13,4-12,9 Ma 14,1-13,0 Ma
13,3-10,9 Ma 12,2-10,4 Ma
8,7 Ma
5,5-5,2 Ma5,2-4,5 Ma5,0-4,1 Ma 5,3 Ma
11,3 Ma11,8-11,5 Ma10,9-10,7 Ma
14,7 Ma16,7-14,7 Ma
27,9 Ma
25,3 Ma
20,7 Ma
16,7 Ma15,5 Ma
7,4 Ma
6,6 Ma
5,6-5,2 Ma5,7-3,7 Ma
24,1-23,4 Ma
Hiatus
Hiatus
Fig. 5
Ine T. Gjeldvik, Van Pham, Fridtjof Riis, Tor EidvinNorwegian Petroleum Directorate (NPD),PO box 600, N 4003 Stavanger Norway
Drawings:Arne Bjørøen, Rune Goa
Storing of CO2 in the Utsira Formation is well document-ed, and since 1996, one megaton of CO2 has been injected at the Sleipner Field in the Norwegian sector block 15/9. The Utsira Formation (Upper Miocene to Lower Pliocene) is a shallow marine, sandy deposit which underlies Up-per Pliocene-Pleistocene sandy deposits of the Nordland Group and overlies Middle Miocene sandy deposits (sug-gested called Eir Formation by Eidvin et al., 2013) and the Skade Formation (Lower Miocene). The proximal part of this sandy system lies in the UK sector. In that areas the deposits are deltaic and are called Hutton sand (informal).
The Utsira Formation and the Skade Formation constitute the main part of this sandy system and are considered as a single aquifer. The Utsira Formation covers an area which is 450 km in North-South direction and 90 km in East-West direction. The Norwegian Petroleum Directo-rate (NPD) has remapped and calculated the total storage potential in a southern depo-center of this aquifer system. A reservoir simulation model covers an area of 1600 km2 of the southern Skade-Utsira depo-center, and the model estimates a capacity of one gigaton.
The Utsira Formation extends from quadrant 34 in the north, to quadrant 15 in the
south. It is deposited in a shallow marine environment and is reworked by tidal
currents. The red polygon to the south defines the southern depocenter.
Underlying the Utsira Formation, the Skade Formation extends from quadrant 30 to quadrant 16 and is deposited mainly as turbidites. The red rectangle shows the 1600 km2 area covered by the reservoir
simulation model.
A general observation is that the CO2 plume will migrate upwards and follow the
topography. Local highs are created as a response to differential compaction where
sand is deposited on shale. These highs will trap the CO2 as it moves up towards
the NW. Red line indicates area shallower than 700 m depth. Here the CO2 behaves
as a gas, hence not suitable for storing. Note that in case a and b (4 versus 5 wells)
it’s relative little difference, as seen in the curve to the right. Approximately 170 Mt
can be injected in the Utsira-Skade aquifer within the segment model.
Post Eocene lithostratigraphy of the Norwegian North Sea (after Eidvin et al. 2013)
This geosection illustrates how four different delta sands, which constitute the outer delta front of the Hutton sand system (informal name used in UK waters only) are deposited. In Norwegian waters the lower Miocene Skade Formation is turbiditic in origin and overlays Oligocene mudstones. The Utsira Formation overlays a mud prone distal Middle Miocene unit and thins out west from the delta front towards the 25/1-8S area (overlaying sandy Middle Miocene deposits). An Upper Pliocene delta builds on top of the Utsira Formation in the 25/2-10S area.
(Eidvin, T., Riis,F. & Gjeldvik I.T.; NGF Winter Conference 2013
“ The Upper Miocene-Lower Pliocene Utsira Formation in the northern North Sea”)
The Skade Fm, Lower Miocene, consists of marine sandstones (mainly turbidites) deposited over a large area of the Viking Graben (From 30/5-2 in the north, to 15/6-7 in the south ). The maximum thickness exceeds 300 m and decreases rapidly towards the south and east, where the sands terminate towards large shale diapirs.
a b c d
abc
6°5°4°3°2°1°
62°
61°
60°
59°
58°
Depth to the Utsira Fm262 m
1459 m
Contour interval 100 m
b b’15/6-7
15/6-9 S
15/9-1 S
a a’25/1-8 S
25/2-10 S
40 km
Upper Pliocene andPleistocene Delta
UTSIRA FORMATION
SKADE FORMATION
25/2-10S25/1-8S
370 md455 md
TWT(ms)200
1000
735 md
475 md520 md
1090 md
md = Measured depth
Basal Nordland Group (clay)
Lower Miocene
Oligocene diapirsNanna(informal, basalLower Miocene)
Upper Oligocene sand
Upper Pleistocene
Upper Oligocene mudstones
Middle Mioceneunconformity/re�ector
Upper Pliocene wedge(glacial diamicton)
Middle Miocene
Hutton sand (informal) according to Gregersen & Johannessen (2007)
Upper Miocene-Lower Pliocene
Basal Nordland Group (sand)
Seabed
W E
OD 1304030
Fig. 22
a’
a
W E15/6-9S 15/6-7
Oligocene
Quarternary
Utsira Formation SB
Skade Formation
Pliocene wedge
Seabed
Glacial channels
0
250
500
750
1000
1250
1500
55 km
Middle Miocene shale
b’b
700m
ReferencesEidvin, T., Riis, F., Rasmussen, E. S. and Rundberg, Y., 2013. Investigation of Oligocene to Lower Pliocene depos-its in the Nordic area. NPD Bulletin No 10. Available from the internet: http://www.npd.no/engelsk/cwi/pbl/NPD_papers/Hyperlink-NPD-Bulletin-10.pdf. Accessed April 28, 2014.
Eidvin, T., Riis,F. & Gjeldvik I.T.; NGF Winter Conference 2013The Lower Oligocene-Lower Pliocene Molo Formation on the inner Norwegian Sea continental shelf
Suggested further reading:Eidvin, T. & Rundberg, Y., 2007: Post-Eocene sstrata of the southern Viking Graben, northern North Sea; integrated biostratigraphic, strontium isotopic and lithostratigraphic study. Norwegian Journal of Geology 87. 391-450.
Eidvin.T., Dybkjær, K., Piasecki, S & Rasmussen, E.S in prep: Strontium isotope stratigraphy based on analyses of mollusk tests from the upper Oligocene –Miocene succession in Denmark with correlation to the Norwegian continental shelf.
Gregersen, U. & Johannessen, P.N., 2007: Distribution of the Neogene Utsira Sand and Hutton Sand, and the succeeding deposits in the Viking Graben area, North Sea. Marine and Petroleum Geology 24 p 591-606.
Halland et al, 2014: NPD publication, CO2 Storage Atlas Norwegian Continental Shelf.
Pham, V.T.H., Riis, F., Gjeldvik, I.T., Halland, E.K., Tappel, I.M., Aagaard, P., 2013: Assessment of CO2 injection into the south Utsira-Skade aquifer, the North Sea, Norway, Energy, Volume 55, p 529-540.
www.npd.no
Norway
co2 storage atLas norwegian continentaL sHeLF
norwegian continentaL sHeLFco2 storage atLas
norwegian continental shelf
co2storage atLas
CO2 storage in the Utsira-Skade aquifer
