Evaluation of CO2 Storage Possibilities on the Norwegian Continental Shelf

Available online at www.sciencedirect.com ScienceDirect

Energy Procedia 63 ( 2014 ) 5192 – 5199

GHGT-12

Evaluation of CO2 Storage possibilities on The Norwegian Continental Shelf

Eva K.Halland1, Fridtjof Riis1*

1 Norwegian Petroleum Directorate (NPD), Pb600, 4003 Stavanger, Norway

Abstract

To get an overview of the possibility to inject and store CO2 in a safe and effective way offshore Norway, possible storage sites has been mapped and evaluated. A total of 27 geological formations have been individually assessed, and grouped into saline aquifers together with several

mapped and dry-drilled structures. The evaluation of geological volumes suitable for injecting and storing CO2 can be viewed as a step-wise approximation which is presented with a pyramid representing the maturity of the storage sites. The assessed aquifers have been characterized according to the guidelines, which have been developed for this study.

© 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license ©(http://creativecommons.org/licenses/by-nc-nd/3.0/ 2013 The Authors. Published by Elsevier Ltd.). SelectionPeer-review and under peer-review responsibility under of theresponsibility Organizing Committee of GHGT. of GHGT-12

Keywords: CO2, Storage Atlas, geological formations, saline aquifers, capacity

1. Introduction

The CO2 Storage Atlas of the Norwegian Continental Shelf [1] has been prepared by the Norwegian Petroleum Directorate (NPD), at the request of the Ministry of Petroleum and Energy. The studied areas are located in parts of the Norwegian Continental Shelf (NCS) which are opened for petroleum activity. The main objectives have been to identify safe and effective areas for long-term storage of CO2 and to avoid possible negative interference with ongoing and future petroleum activity. This atlas is also to form the basis for any terms and conditions to be set for future development of a storage site offshore Norway. This work is based on knowledge from more than 40 years of petroleum activity and from the ongoing CO2 storage projects with 17 years of experience with CO2 storage from the

* Corresponding author. Tel.: . E-mail address: HYDKDOODQG#QSGQR

1876-6102 © 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the Organizing Committee of GHGT-12 doi: 10.1016/j.egypro.2014.11.550 Eva K. Halland and Fridtjof Riis / Energy Procedia 63 ( 2014 ) 5192 – 5199 5193

Sleipner Vest Field into the Utsira formation and from the Snøhvit Field (Barents Sea) from 2008. Valuable knowledge has also been gained through the Norwegian R&D and Demo project Climit, UNIS CO2 Lab and several large EU projects on storage and monitoring. This work is based on the three previous Atlas from The North Sea (2011), The Norwegian Sea (2012) and The Barents Sea (2013) (Fig.1).

Fig.1 CO2 Storage Atlas of the Norwegian Continental Shelf

2. Access to Data

The study presented here is based on detailed work on all relevant geological formations and hydrocarbon fields in the NCS. NPD has access to all data collected from the petroleum activity and has a national responsibility for the data [2]. The authority’s access to collected and analysed data is stipulated in law. These data, together with many years of dedicated work to establish geological play models for the NCS have given us a good basis for the work presented. Seismic data (fig.2) and results from exploration and production wells form an extensive database . 27 geological formations have been individually assessed in this study (fig.7). Studies have shown that it may be possible to store large amount of CO2 on the NCS. Several saline aquifers are present and many dry-drilled structures proven.

63°

Data availability Wells 3D seismic 2D seismic

62° Approximate limit for significant hydrocarbon migration

61°

60°

Brønnøysund

59°

Namsos

58°

TrondheimStjørdal

Kristiansund 57°

Molde

Ålesund Hammerfest # Data availability

3D seismic

Måløy 2D Seismic 56° 2° 3° 4° 5° 6° 7° 8° 9° 10°

Fig. 2 Seismic coverage in The North Sea (a) The Norwegian Sea (b) and The Barents Sea (c)

3. Methodology

Depending on their specific geological properties, several types of geological formations can be used to store CO2. Offshore Norway, the greatest potential capacity will be in deep saline-water saturated formations or in depleted oil and gas fields. Injected and stored as a supercritical fluid CO2 will migrate through the interconnected pore spaces in the rock, just like other fluids (water, oil, gas). To be suitable for CO2 storage, saline formations need to have sufficient porosity and permeability to allow large volumes of CO2 to be injected in a supercritical state at the rate it is supplied at. It must further be overlain by an impermeable cap rock, acting as a seal, to prevent CO2 migration 5194 Eva K. Halland and Fridtjof Riis / Energy Procedia 63 ( 2014 ) 5192 – 5199

into other formations or to sea.CO2 is held in-place in a storage reservoir through one or more of five basic trapping mechanisms: stratigraphic, structural, residual, solubility, and mineral trapping. Generally, the initial dominant trapping mechanisms are stratigraphic trapping or structural trapping (fig.3) or a combination of the two. An aquifer is a body of porous and permeable sedimentary rocks where the water in the pore space is in communication throughout (fig.4). Aquifers may consist of several sedimentary formations and cover large areas. They may be somewhat segmented by faults and by low permeable layers acting as baffles to fluid flow.

Formation

Formation Formation Formation Group

Formation Aquifer Formation Formation

Permeable formations

Fig.3 Trapping mechanism (Structural traps and Stratigraphic traps) Fig.4 Relation between geological formations and aquifers

4. Characterization of the saline aquifers

Aquifers and structures have been characterized in terms of capacity, injectivity and safe storage of CO2. To complete the characterization, the aquifers are also evaluated according to the data coverage and their technical maturity. Some guidelines (a check list) were developed to facilitate characterization (fig.5). The scores for capacity, injectivity and seal quality are based on evaluation of each aquifer/structure. The checklist for reservoir properties gives a more detailed overview of the important parameters regarding the quality of the reservoir. A corresponding checklist has been developed for the sealing properties. Evaluation of faults and fractures through the seal, in addition to old wells penetrating the seal, provides important information on the sealing quality. The data coverage is colour-coded to illustrate the data available for each aquifer/structure. Characterization and capacity estimates will obviously be more uncertain when data coverage is poor. The scores for capacity, injectivity and seal were determined from the individual parameters established in the guidelines. The methods used for characterization of reservoir properties are similar to well-established methods used in petroleum exploration. Characterization of cap rock and injectivity is typically conducted in studies of field development and to some extent in basin modelling. For evaluation of regional aquifers in CO2 storage studies, the mineralogical composition and the petrophysical properties of the cap rocks are rarely well known. In order to characterize the sealing capacity in this study, we have mainly relied on regional pore pressure distributions and data from leak-off tests combined with observations of natural gas seeps. In exploration wells on the Norwegian shelf, pressure differences across faults and between reservoir formations and reservoir segments are commonly observed. Pressure differences give indications of the sealing properties of cap rocks and faults. Based on observations in the hydrocarbon provinces, combined with a general geological understanding, one can use the sealing properties in explored areas to predict the properties in less explored or undrilled areas. Natural seepage of gas is commonly observed in the hydrocarbon provinces in the Norwegian continental shelf and is expected from structures and hydrocarbon source rocks where the pore pressure is close to or exceeds the fracture gradient (fig6). Seepage at the sea floor can be recognized by biological activity and by free gas bubbles. Seismically, seepage is indicated by gas chimneys or pipe structures. The seepage rates at the surface show that the volumes of escaped gas through a shale or clay dominated overburden are small in a time scale of a few thousand years. Rapid leakage can only take place if open conduits are established to the sea floor. These could be created along wellbores or by reactivation of faults or fractures. Established natural seepage systems are also regarded as a risk factor for CO2 injection. Eva K. Halland and Fridtjof Riis / Energy Procedia 63 ( 2014 ) 5192 – 5199 5195

In summary, the capacity of each aquifer is given in the tables as a deterministic volume. The injectivity and sealing properties are indicated by scores 1 to 3. The characterization is based on a best estimate of each parameter. Uncertainty is not quantified, but is indicated by the colour coding for data availability and maturity.

CHARACTERIZATION OF AQUIFERS AND STRUCTURES

Criteria Definitions, comments

Reservoir quality Capacity, communicating volumes 3 Large calculated volume, dominant high scores in checklist 2 Medium - low estimated volume, or low score in some factors

1 Dominant low values, or at least one score close to unacceptable Injectivity 3 High value for permeability * thickness (k*h) 2 Medium k*h 1 Low k*h Sealing quality Seal 3 Good sealing shale, dominant high scores in checklist 2 At least one sealing layer with acceptable properties 1 Sealing layer with uncertain properties, low scores in checklist Fracture of seal 3 Dominant high scores in checklist 2 Insignificant fractures (natural / wells) 1 Low scores in checklist Other leak risk Wells 3 No previous drilling in the reservoir / safe plugging of wells 2 Wells penetrating seal, no leakage documented 1 Possible leaking wells / needs evaluation

Data coverage Good data coverage Limited data coverage Poor data coverage

Other factors: How easy / difficult to prepare for monitoring and intervention. The need for pressure relief. Possible support for EOR projects. Potential for conflicts with future petroleum activity. Fig. 5 Characterization of aquifers and structures, with regard to reservoir and seal

5. Estimation of storage capacity

CO2 can be stored in produced oil and gas fields, or in saline aquifers. In a producing oil field, CO2 can be used to combine storage with enhanced recovery. In saline aquifers, CO2 can be stored as dissolved CO2 in the water phase, free CO2 or residual (trapped) CO2 in the pores. When fluid is injected into a closed or half-open aquifer, pressure will increase. The relation between pressure and injected volume depends on the compressibility of the rock and the fluids in the reservoir. The solubility of CO2 in the different phases will also play a part. Safe injection of CO2 or any other fluid requires that the injection pressure in the reservoir is less than the fracturing pressure. Pressure increase can however be mitigated by production of formation water. The fracturing pressure depends on the state of stress in the bedrock and is typically 10-30 % lower than the lithostatic pressure. Fracturing gradients were estimated by comparing pore pressures in overpressured reservoirs with data from leak-off tests. Storage capacity depends on several factors, primarily the reservoir pore volume and the fracturing pressure. It is important to know if there is communication between multiple reservoirs, or if the reservoirs are in communication with larger aquifers.

6. Geological development of the Norwegian Continental Shelf

North Sea The basic structural framework of the North Sea is mainly the result of Upper Jurassic/ Lower Cretaceous rifting, partly controlled by older structural elements (fig.8a). In the southern part, thick Permian evaporate sequences were deposited (Zechstein). Salt tectonics (halokinesis) is important for generation of closed structures, including hydrocarbon traps and also as a control on local topography and further sedimentation [3]. Due to their deep burial, Pre-Jurassic strata have not been evaluated for CO2 storage potential [4]. Large deltaic systems containing sand, shale and coal were developed in the northern part and the Horda Platform (Brent group). In the Norwegian- Danish Basin and the Stord Basin, the Vestland group contains deltaic sequences overlain by shallow marine/ marginal marine sandstones. The most important Jurassic rifting phase took place during the Late Jurassic the earliest Cretaceous. During this tectonic episode, major block faulting caused uplift and tilting and created considerable local topography with erosion and sediment supply. In the Paleocene/Eocene a series of submarine fans sourced from the Shetland Platform area towards the east into the study area. 5196 Eva K. Halland and Fridtjof Riis / Energy Procedia 63 ( 2014 ) 5192 – 5199

&Û m 0 50 Û í

40 í

í 30 í Bathymetry Temp. Gradient Û 20 í Û Û Û Û Û Fig.6Temperature gradients obtained from drill stem tests in the NCS Fig.7 Mapped aquifers on NCS

These sands interfinger with marine shales in both the Rogaland and the Hordaland groups [5]. In the Miocene a deltaic system had developed from the Shetland Platform into the Norwegian sector of NS, and is represented by the Skade and Utsira Formations. Due to uplift and quaternary glacial erosion of the Norwegian mainland, thick Neogene sequences were deposited into the NS. This led to burial of the Jurassic source rocks to depths where hydrocarbons could be generated and the seals were effective. In the western provinces, Paleogene and older aquifers contain hydrocarbons. In the eastern part, hydrocarbon discoveries have only been made in local basins. In the eastern area, all the large aquifers have been evalueted based on the established methodology (fig.8 b). In the petroleum provinces, it is considered that exploration and production activities will continue for many years to come. The most realistic sites of CO2 storage will be some of the abandoned fields, in particular the gas fields. Consequently, an indication of the storage capacity of the fields has been given, but no aquifer volumes have been calculated. Some of the oil fields are considered to have a potential for use of CO2 to enhance oil recovery (EOR). Some of the CO2 used for EOR will remain trapped. The capacity for this type of CO2 trapping has not been calculated.

Norwegian Sea The Norwegian Sea covers most of the continental margin between approximately 62o and 69o30’ N. The tectonic history can be divided into three major episodes: Final closure of the Iapetus Ocean during the Caledonian Orogeny (Late Silurian/ Early Devonian), a series of mainly extensional deformation episodes (Late Devonian to Paleocene), culminating with the continental separation between Greenland and Eurasia, active seafloor spreading in the North Atlantic between Eurasia and Greenland (Earliest Eocene to present) [6] (fig.9a). The area with the best potential for o o storage of CO2 is the Trøndelag Platform (63 to 67 N), one of the main structural elements of the Norwegian Sea. The areas further west and south are considered less suitable for storage of CO2 due to the active production of hydrocarbons, high temperature and high pressure and the depth of the relevant reservoirs. In the Norwegian Sea, the general conditions are met in the Trøndelag Platform including the Nordland Ridge and in the Møre Basin (fig.9b). Potential CO2 storage in the shelf slope and deep sea provinces of the Norwegian Sea has not been evaluated. The aquifers in the Froan Basin have a consistent dip of 1-2 degrees from the Norwegian coast to the basinal areas. In the case of permeable beds occurring along the dip slope there is a risk that CO2 injected down dip can migrate up to where the aquifer is truncated by the Quaternary glacial sediments. This setting is similar to several other aquifers in the NCS [7]. The main objective of our study has been to estimate the amount of Eva K. Halland and Fridtjof Riis / Energy Procedia 63 ( 2014 ) 5192 – 5199 5197

CO2 that can be safely stored, mainly based on reservoir simulation. Of particular interest is the understanding of the timing and extent of long distance CO2 migration.

Age Formations & Groups Evaluated Aquifers 3 Pliocene Piacenzian Zanclean 6 Møre Messinian Utsira Fm. 9 To r t o n i a n 11 Miocene Serravallian Ve Mb. Utsira and Skade Formations Basin 13 Langhian 15 Burdigalian 17 Skade Fm. 19 Aquitanian 22 Chattian 62° 24 26 Oligocene 28 Rupelian 30 33 Priabonian 35 Bartonian Grid Fm. 37 39 42 Eocene Lutetian 44 46 48 Ypresian Tampen Spur 50 Paleogene Neogene Frigg Fm. Frigg Field Abandoned Gas Field 53 Balder Fm. Thanetian Sogn GrabenHorda 55 Fiskebank Fm. Fiskebank Fm. 57 Paleocene Selandian 59 Basin Danian Platform 62 64 Maastrichtian 66 Tor Fm. East Shetland East 68 70 73 Campanian 75 Bergen 77 Hod Fm. 79 Late 82 Santonian 84 Coniacian Oslo 86

Platform 88 Turonian Stord 91 East Shetland East 93 Cenomanian 95 Basin 97 99 102 Albian 105 108

Viking Graben 112 Cretaceous Øygarden Fault complex Fault Øygarden 115 Aptian 118 Early 122 Utsira Stavanger 125 Barremian 128 Hauterivian 132 High Valanginian 135 138 Berriasian Sele Stavanger 142 145 Tithonian Draupne Fm. Stord Basin Jurassic Model Åsta Graben 148 High Platform Late Kimmeridgian 152 Ula Fm. Stord Basin Mounds * Sørvestlandet High Central Graben 155 Oxfordian 158 Egersund Callovian 162 Hugin Fm. Hugin East Bathonian Sandnes Fm. Basin 165 Middle Farsund Basin Bajocian Sleipner Fm. Bryne / Sandnes Formations South * 168 Brent Gp. Bryne Fm. Aalenian Bryne / Sandnes Formations Farsund Basin Fjerritslev Fault complex 172 175 Jurassic Toarcian 178 Johansen Fm. 182 Johansen and Cook Formations * Pliensbachian Cook Fm. Norwegian-Danish Basin 185 Early 57° 188 Sinemurian 192 195 Hettangian Statfjord Gp. Nansen Eiriksson Raude Gassum Fm. 198 Rhaetian Gassum Fm. 202 205 Skagerrak Fm. Norian 208 212 Late 215

218 Carnian Formations not 222 Triassic evaluated 225 228 Middle Ladinian 232 * Evaluated prospects Fig.8. Structural elements in the Norwegian part of the North Sea (a), evaluated geological formations and aquifers (b)

Barents Sea The Barents Sea is located in an intracratonic setting between the Norwegian mainland and Svalbard. It has been affected by several tectonic episodes after the Caledonian orogeny ended in Late Silurian/Early Devonian [8]. The area evaluated for CO2 storage is defined to the west by the N-S to NNE-SSW trending Ringvassøy- Loppa and Bjørnøyrenna Fault Complexes, to the south/southeast by the Troms-Finnmark Fault Complex and the Finnmark Platform, to the north by an eastwest line approximately along the 73o N parallel, and to the east by a north-south line running approximately along the 28oE meridian. The southern Barents Sea shelf is divided into several main structural elements. The most important ones are: The Hammerfest and Nordkapp Basins, the Finnmark and Bjarmeland Platforms and the Loppa High (fig.10a). Cenozoic tectonism and Quaternary glacial erosion has caused the maximum burial of these source rocks in the evaluated area occurred in the past [9]. The reservoir porosity and permeability are related to the temperature and pressure at maximum burial. Due to extensive erosion, good reservoir quality is encountered only at shallower depth than what is found in the North Sea and Norwegian Sea. Hydrocarbons and traces of hydrocarbons have been found in several aquifers, and at the present stage in exploration, it is thought that most of the area selected for evaluation of CO2 storage will also be subject to further exploration and exploitation by the petroleum industry. Consequently, storage of CO2 in the southern Barents Sea must take place in accordance with the interests of the petroleum industry. The main storage options considered in this study are limited to structurally defined traps, and to depleted and abandoned gas fields. In areas where the pressure exceeds the miscibility pressure of CO2 and oil, one might consider using CO2 injection to recover some of these oil resources (CCUS). The main aquifer system in the study area consists of Lower and Middle Jurassic sandstones belonging to the Realgrunnen Subgroup (fig.10b). This aquifer system can be defined in three distinct geographical areas which are described in the following section [10]. The Bjarmeland Platform is located north of 72°N and extends beyond 74°N, north of the Nordkapp Basin. The boundary between the Hammerfest Basin aquifer and the Bjarmeland Platform aquifer is transitional. According to well data, the best quality aquifer in the Bjarmeland Platform is found in the saddle area between the Nordkapp and Hammerfest Basins. The structuring of the Bjarmeland Platform is mainly related to salt tectonics which has resulted in domes, 5198 Eva K. Halland and Fridtjof Riis / Energy Procedia 63 ( 2014 ) 5192 – 5199

rim synclines and normal faults. The pore pressure is hydrostatic. It is likely that the degree of communication within the regional Bjarmeland Platform aquifer is not as good as within the upper part of the Hammerfest Basin aquifer (Stø Formation), due to reduced thickness and more heterolithicfacies.

5°0'0"E 10°0'0"E 15°0'0"E Age Formations & Groups Evaluated Aquifers 3 Pliocene Piacenzian Zanclean 6 Messinian 9 Tortonian Jennegga High Utrøst Ridge 11 Miocene Serravallian 13 Langhian 15 Burdigalian 17 Aquitanian Lofoten Basin 19 22 Chattian Havbåen Sub-basin 24 26 Oligocene 28 Rupelian Vøring Marginal High Ribban Basin 30 68°0'0"N Lofoten Ridge 33 Priabonian Røst High 68°0'0"N 35 Bartonian 37 39 Lutetian Marmæle Spur 42 Eocene Skomvær Sub-basin 44 46 Hel Graben 48 Ypresian 50 Paleogene Neogene Kvalnesdjup Graben 53 Thanetian 55 Fenris Graben Ribban Basin 57 Paleocene Selandian 59 Vestfjorden Basin Danian Egga Fm. Egga Fm. Nyk High Någrind Syncline 62 64 Maastrichtian 66 68 70 73 Campanian 75 77 Utgard High Træna Basin Grønøy High 79 Late 82 Santonian Gjallar Ridge 84 Coniacian Lysing Fm. Nordland Ridge 86 88 Turonian Vigrid Syncline Ytreholmen Fault Zone 91 Lange Fm. Fles Fault Complex Rødøy High A 93 Cenomanian 95 66°0'0"N 97 99 Helgeland Basin 66°0'0"N 102 Albian Dønna Terrace 105 108 Revfallet Fault Complex B' Vøring Marginal High Ytreholmen Fault Zone Sør High Ylvingen Fault Zone 112 Cretaceous Revfallet Fault Complex Vega High 115 Aptian Lange Fm. Fles Fault Complex 118 Early 122 125 Barremian Trøndelag Platform Halten Terrace 128 Hauterivian Møre Marginal High Ellingråsa Graben 132 Valanginian Grinda Graben 135 Lange Fm. 138 Slettringen RidgeRås Basin Berriasian Sklinna Ridge B 142 145 Tithonian Gimsan Basin 148 Late Kimmeridgian 152 Rogn Fm. Rogn Fm. 155 Oxfordian Grip High Froan Basin Møre Basin 158 Callovian A' 162 64°0'0"N Bathonian 64°0'0"N 165 Middle Bajocian Garn Fm. *Garn Fm. 168 Fangst Gp. Aalenian 172 Ile Fm. *Ile Fm. 175 Jurassic Toarcian Structural elements 178 182 Vigra High Pliensbachian Cretaceous High 185 Early Frøya High Tilje Fm. *Tilje Fm. 188 Deep Cretaceous Basin Sinemurian 192 Åre Fm. Ona HighMøre-Trøndelag Fault Complex Marginal Volcanic High 195 Hettangian *Åre Fm. Gossa High 198 Rhaetian Palaeozoic High in Platform Giske High 202 205 Platform Norian Møre-Trøndelag Fault Complex 208 Gnausen HighMøre-Trøndelag Fault Complex Pre-Jurassic Basin in Platform 212 Late Slørebotn Sub-basin Shallow Cretaceous Basin in Platform 215 218 Carnian

Terraces and Intra-Basinal Elevations 222 Triassic Ta mp en Sp ur 225 Volcanics 62°0'0"N Selje HorstØygarden Fault Complex 228 62°0'0"N Middle Ladinian Måløy Slope 232

5°0'0"E 10°0'0"E * Ev aluated prospects Fig.9 Structural elements in The Norwegian Sea (a), evaluated geological formations and aquifers (b)

7. Storage Capacity on Norwegian Continental Shelf

An overview of the results of this study is illustrated by maturation pyramids for the North Sea, Norwegian Sea and southern Barents Sea. All areas have a significant potential for CO2 storage. The total storage capacity of the North Sea aquifers is much larger than for the other regions. One reason for this is that in the North Sea there are important aquifers at several stratigraphic levels, while in the Norwegian Sea and Barents Sea, Jurassic formations will be the main target for CO2 injection. The injectivity of the studied aquifers and the sealing properties of their cap rocks are considered to be acceptable or good, mainly because poor quality reservoir formations were excluded from the evaluation. Sealing properties are typically characterized as slightly lower in the Barents Sea than in the other regions. This is due to the Cenozoic and Quaternary uplift history and widespread evidence of hydrocarbon seepage. In the North Sea and Norwegian Sea the studied aquifers belong to areas where conflicts of interests with petroleum industry are not very likely. Most of them were characterized to the green level in the maturation pyramid. Due to a geological setting with source rocks at several stratigraphic levels and a complex burial history, most parts of the southern Barents Sea were considered to be of interest for future petroleum exploration, consequently the studied aquifers were classified to belong to the blue level.

Acknowledgements

The CO2 Storage Atlas has been developed by a team at the Norwegian Petroleum Directorate. The support from colleagues through discussions, and the support from the Ministry of Petroleum and Energy have been of great importance. Sincere thanks to Christian Magnus, Jasminka Mujezinovic, Rita Sande Rød, Andreas Bjørnestad, Maren Bjørheim, Inge M.Tappel, Van T H Pham, Ine Gjeldvik, Wenche T.Johansen, Ida M. Meling, Arne Bjørøen, Rune Goa and Asbjørn Thon for constructive contributions. The Norwegian CO2 Storage Forum has contributed with its expertise in our meetings over the last two years. Eva K. Halland and Fridtjof Riis / Energy Procedia 63 ( 2014 ) 5192 – 5199 5199

Age Formations Evaluated Aquifers

Norwegian North Sea Aquifers Piacenzian 5 Pliocene Zanclean Messinian Tortonian Miocene Serravallian Langhian Burdigalian Neogene Aquitanian 23 Chattian Oligocene Rupelian 34 Priabonian Bartonian

Eocene Lutetian

Ypresian Paleogene 56 Thanetian Paleocene Selandian Danian 66 Maastrichtian 72

Campanian

Late 84 Santonian 86 Coniacian 90 Turonian 94 Cenomanian 100

Albian

113 Cretaceous Aptian Early 125 Barremian 129 Hauterivian 133 Valanginian Knurr Fm. 140 Berriasian 145 Tithonian Hekkingen sand 152 Late Kimmeridgian 157 Oxfordian

164 166 Callovian Bathonian 168 Middle Bajocian 170 Aalenian 174

Toarcian Jurassic Stø Fm. Stø Fm. 183

Early Pliensbachian 191

Sinemurian Nordmela Fm. Nordmela Fm.

199 201 Hettangian Tubåen Fm. Tubåen Fm. Rhaetian

209

Late Norian Fruholmen Fm. Fruholmen Fm.

227

Carnian Snadd Fm. Snadd Fm. Triassic

237 Ladinian 242 Middle Kobbe Fm. Kobbe Fm. Anisian 247 Olenekian Klappmys Fm. Klappmys Fm. Lower Havert Fm. 252 Induan Havert Fm. Fig.10 Structural elements in The Barents Sea (a), evaluated geological formations and aquifers (b)

The North Sea Based on injection history The Norwegian Sea Based on injection history The Barents Sea Based on injection history

Development of injection site Development of injection site Development of injection site

Injection Suitable for long term storage Injection Suitable for long term storage Injection Suitable for long term storage

Exploration Exploration Exploration

Effecti Gt Effecti GGt Effecti GGt vve and 1 G vve and 5 vve and 2 saf 1.1 G saf saf e storage Theoretical volume e storage 0.15 Theoretical volume e storage 0.02 Theoretical volume Cut off criteria on volume/conflict of interest Cut off criteria on volume/conflict of interest Cut off criteria on volume/conflict of interest

Volume calculated on average porosity and thickness 43 Gt + 24 Gt (fields) Volume calculated on average porosity and thickness4.4 Gt + 1.1 Gt (fields) Volume calculated on average porosity and thickness0.07 Gt + 0.2 Gt (fields) 4 Gt Increased technical Increased technical 7.24 Gt Gt Increased technical maturity maturity maturity

References and Web resources [1] Halland et al, 2014: NPD publications CO2 Storage Atlas- Norwegian Continental Shelf [2] NPD fact pages http://factpages.npd.no/factpages/Default.aspx?culture=en [3] Isaksen, D, and Tonstad, K. 1989. NPD Bulletin no.5. A revised Cretaceous and Tertiary lithostratigraphic nomenclature for the Norwegian North Sea. 65 pp. English text. IS BN 82-7257-241-9. http://www.npd.no/en/Publications/NPDbulletins/ 255-Bulletin-5/. [4] Vollset, J, and Doré, A G (editors). 1984. NPD Bulletin no.3. A revised Triassic and Jurassic lithostratigraphic nomenclature for the Norwegian North Sea.53 pp., English text. IS BN 82-7257-155-2. http://www.npd.no/en/Publications/NPDbulletins/ 253-Bulletin-3/ [5] Deegan, C E, and Skull, B J. 1977. NPD Bulletin no.1.A standard lithostratigraphic nomenclature for the central and northern North Sea. 36 pp., 27 maps, English text (Also published as Institute of Geological Sciences Report 77/25.) http:// www.npd.no/en/Publications/NPD- bulletins/251-Bulletin-1/ [6] NPD Bulletin No 8 (1995) Structural elements of the Norwegian continental shelf. Part II: The Norwegian Sea Region. http://www.npd.no/no/Publikasjoner/NPD-bulletin/258-Bulletin8/ [7] NPD Bulletin No 4 (1988) A lithostratigraphic scheme for the Mesozoic and Cenozoic succession offshore mid- and northern Norway http://www.npd.no/no/Publikasjoner/NPD-bulletin/254-Bulletin-4/ [8] Gabrielsen,R.H., Færseth,R.B., Jensen,L.N., Kalheim,J.E. and Riis,F. 1990: Structural elements of the Norwegian continental shelf. Part I: The Barents Sea Region. NPD Bulletin No 6, 33 p. [9] Henriksen, E., Bjørnseth, H. M., Hals, K. T., Heide, T., Kiryukhina,T., Kløvjan, O. S., Larssen, G. B., Ryseth, A. E., Rønning, K., Sollid, K. and Stoupakova, A. 2011. Uplift and erosion of the greater Barents Sea: impact on prospectivity and petroleum systems, Geological Society, London, Memoirs 2011, v.35; p217-281. doi: 10.1144/M35.17 [10] Riis, F., Lundschien, B. A., Høy, T., Mørk, A. and Mørk, M. B. E. 2008. Evolution of the Triassic shelf in the northern Barents Sea region. Polar Research 27, 2008, pp. 318–338.