
How to Cite
Share
Abstract
The renewable energy transition has increased the demand for offshore construction in the Danish North Sea energy sector. This development underpins the need for further investigation of potential geological hazards and associated risks to avoid accidents involving people, the environment or infrastructure. A scientific approach to de-risking requires an understanding of the seabed and the buried geosystems. Understanding geosystems is the first step in the de-risking process of offshore construction. In this study, we review three key geosystem elements in the Danish North Sea, represented by (1) shallow stratigraphy and geomorphology, (2) glacial tectonics and salt movement and (3) subsurface fluid migration. We summarise the current state of knowledge of these geosystem elements and identify multiple risks associated with each geosystem in the region. Such investigations are critical for understanding the geotechnical behaviour of the subsurface and identifying and de-risking of potential geohazards during the construction of future energy developments in the Danish North Sea region.
How to Cite
Share
Copyright (c) 2025 Lasse Tésik Prins, Katrine Juul Andresen, Matthew J Owen, Paul C Knutz

This work is licensed under a Creative Commons Attribution 4.0 International License.
Funding
This study was funded by the Danish Offshore Technology Centre, DTU, Denmark.Downloads
Guest editors: Kaskela Anu (Geological Survey of Finland), Margaret Dolan (Geological Survey of Norway) and Verner Brandbyge Ernstsen (Geological Survey of Denmark and Greenland).
This special issue highlights the application and development of the concepts of geodiversity and geosystem services in a marine context with a specific focus on the Scandinavian [...]
References
- Adegbamigbe, T., Biswas, A., Blaney, J. & Jagtap, A. 2022: The North Sea – a long and proud history. https://jpt.spe.org/twa/the-north-sea-a-long-and-proud-history (accessed Feb 2025).
- Andersen, L.T., Hansen, D.L. & Huuse, M. 2005: Numerical modelling of thrust structures in unconsolidated sediments: implications for glaciotectonic deformation. Journal of Structural Geology 27, 587–596.
- Andresen, K.J. 2012: Fluid flow features in hydrocarbon plumbing systems: what do they tell us about the basin evolution? Marine Geology 332–334, 89–108.
- Andresen, K.J., Dahlin, A., Kjeldsen, K.U., Røy, H., Bennike, O., Nørgaard-Pedersen, N. & Seidenkrantz, M.S. 2021: The longevity of pockmarks – a case study from a shallow water body in northern Denmark. Marine Geology 434, 106440.
- Andresen, K.J., Hepp, D.A., Keil, H. & Spiess, V. 2022: Seismic morphologies of submerged late glacial to Early Holocene landscapes at the eastern Dogger Bank, central North Sea Basin – implications for geo-archaeological potential. Geological Society of London, Special Publications 525, 13–42.
- Andresen, K.J., Huuse, M. & Clausen, O.R. 2008: Morphology and distribution of Oligocene and Miocene pockmarks in the Danish North Sea – implications for bottom current activity and fluid migration. Basin Research 20, 445–466.
- Anthony, D. & Leth, J.O. 2002: Large-scale bedforms, sediment distribution and sand mobility in the eastern North Sea off the Danish west coast. Marine Geology 182, 247–263.
- Batchelor, C.L., Margold, M., Krapp, M., Murton, D.K., Dalton, A.S., Gibbard, P.L., Stokes, C.R., Murton, J.B. & Manica, A. 2019: The configuration of Northern Hemisphere ice sheets through the Quaternary. Nature Communications 10, 1–10.
- Bellwald, B. et al. 2024: Geohazards and engineering challenges related to heterogeneous infill of tunnel calleys. In: Fifth EAGE Global Energy Transition Conference & Exhibition (GET 2024). European Association of Geoscientists & Engineers, 1–5.
- Bellwald, B., Forsberg, C.F. & Vanneste, M. 2023: Multi-disciplinary characterization of sedimentary environments on glaciated margins: implications for engineering of offshore windfarm sites. NSG2023 1st Conference on Sub-surface Characterisation for Offshore Wind 2023, 1–5.
- Bendixen, C., Lamb, R.M., Huuse, M., Boldreel, L.O., Jensen, J.B. & Clausen, O.R. 2017: Evidence for a grounded ice sheet in the central North Sea during the early middle pleistocene donian glaciation. Journal of the Geological Society of London 175, 291–307.
- Bennet, M.R. & Glasser, N.F., 2009. Glacial geology – ice sheets and landforms, Ch. 8.1 Direct glacial Sedimentation. 2nd ed., Wiley-Blackwell, Chichester, West Sussex.
- Benvenuti, A., Šegvić, B. & Moscariello, A. 2018: Tunnel valley deposits from the southern North Sea – material provenance and depositional processes. Boreas 47, 625–642.
- Bienen, B., Qiu, G. & Pucker, T. 2015: CPT correlation developed from numerical analysis to predict jack-up foundation penetration into sand overlying clay. Ocean Engineering 108, 216–226.
- Bogoyavlensky, V., Bogoyavlensky, I., Nikonov, R. & Kishankov, A. 2020: Complex of geophysical studies of the seyakha catastrophic gas blowout crater on the Yamal peninsula, Russian Arctic. Geosciences 10, 215.
- Cameron, T.D.J., Stoker, M.S. & Long, D. 1987: The history of Quaternary sedimentation in the UK sector of the North Sea Basin. Journal of the Geological Society 144, 43–58.
- Cartwright, J., Huuse, M. & Aplin, A. 2007: Seal bypass systems. AAPG Bulletin 91, 1141–1166. https://doi.org/10.1306/04090705181
- Chuvilin, E. et al. 2020: A gas-emission crater in the erkuta river valley, yamal peninsula: characteristics and potential formation model. Geosciences 10(5), 170.
- Cook, M. et al. 2014: Guidance notes for the planning and execution of geophysical and geotechnical ground investigations for offshore renewable energy developments. The Society for Underwater Technology. ISBN: 0906940540. Pp. 1–48, London.
- Copping, A.E., Freeman, M.C., Gorton, A.M. & Hemery, L.G. 2020: Risk retirement – decreasing uncertainty and informing consenting processes for marine renewable energy development. Toxics 8, 1–22.
- Cotterill, C., Phillips, E., James, L., Forsberg, C. & Tjelta, T.I. 2017a: How understanding past landscapes might inform present–day site investigations: a case study from Dogger Bank, southern central North Sea. Near Surface Geophysics 15, 403–414.
- Cotterill, C.J., Phillips, E., James, L., Forsberg, C.F., Tjelta, T.I., Carter, G. & Dove, D. 2017b: The evolution of the Dogger Bank, North Sea: a complex history of terrestrial, glacial and marine environmental change. Quaternary Science Reviews 171, 136–153.
- Coughlan, M., Fleischer, M., Wheeler, A.J., Hepp, D.A., Hebbeln, D. & Mörz, T. 2018: A revised stratigraphical framework for the Quaternary deposits of the German North Sea sector: a geological-geotechnical approach. Boreas 47, 80–105. https://doi.org/10.1111/bor.12253
- Coughlan, M., Long, M. & Doherty, P. 2020: Geological and geotechnical constraints in the Irish Sea for offshore renewable energy. Journal of Maps 16, 420–431.
- Coughlan, M., Roy, S., O’Sullivan, C., Clements, A., O’Toole, R. & Plets, R. 2021: Geological settings and controls of fluid migration and associated seafloor seepage features in the north Irish Sea. Marine and Petroleum Geology 123, 104762.
- Danish Maritime Authority 2023: Maritime spatial plan. https://www.dma.dk/growth-and-framework-conditions/maritime-spatial-plan (accessed Feb 2025).
- Degraer, S., Carey, D.A., Coolen, J.W., Hutchison, Z.L., Kerckhof, F., Rumes, B. & Vanaverbeke, J. 2020: Special issue on understanding the effects of offshore wind energy development on fisheries: offshore wind farm artificial reefs affect ecosystem structure and functioning – a synthesis. Oceanography 33, 10.
- Dove, D., Evans, D.J.A., Lee, J.R., Roberts, D.H., Tappin, D.R., Mellett, C.L., Long, D. & Callard, S.L. 2017: Phased occupation and retreat of the last British–Irish Ice Sheet in the southern North Sea; geomorphic and seismostratigraphic evidence of a dynamic ice lobe. Quaternary Science Reviews 163, 114–134.
- Emery, A.R., Hodgson, D.M., Barlow, N.L.M., Carrivick, J.L., Cotterill, C.J. & Phillips, E. 2019: Left high and dry: deglaciation of Dogger Bank, North Sea, recorded in proglacial lake evolution. Frontiers in Earth Science 7, 1–27.
- Emery, A.R., Hodgson, D.M., Barlow, N.L.M., Carrivick, J.L., Cotterill, C.J., Richardson, J.C., Ivanovic, R.F. & Mellett, C.L. 2020: Ice sheet and palaeoclimate controls on drainage network evolution: an example from Dogger Bank, North Sea. Earth Surface Dynamics 8, 869–891.
- Etiope, G. 2009: Natural emissions of methane from geological seepage in Europe. Atmospheric Environment 43, 1430–1443.
- Fleischer, M., Abegunrin, A., Hepp, D.A., Kreiter, S., Coughlan & M., Mörz, T. 2022: Stratigraphic and geotechnical characterization of regionally extensive and highly competent shallow sand units in the southern North Sea. Boreas 52, 78–98.
- Frisk, E.L. 2022: The geosystem services concept – what is it and can it support subsurface planning? Ecosystem Services 58, 101493.
- Geological Survey of Denmark and Greenland (GEUS) 2024: Marine raw material database. https://eng.geus.dk/products-services-facilities/data-and-maps/marine-raw-material-database-marta (accessed Feb 2025).
- Gołedowski, B., Nielsen, S.B. & Clausen, O.R. 2012: Patterns of Cenozoic sediment flux from western Scandinavia. Basin Research 24, 377–400.
- Guinan, J., McKeon, C., O’keeffe, E., Monteys, X., Sacchetti, F., Coughlan, M. & Aonghusa, C.N. 2020: Infomar data supports offshore energy development and marine spatial planning in the irish offshore via the emodnet geology portal. Quarterly Journal of Engineering Geology and Hydrogeology 54, qjegh2020-033.
- Hepp, D.A., Romero, O.E., Mörz, T., de Pol-Holz, R. & Hebbeln, D. 2019: How a river submerges into the sea: a geological record of changing a fluvial to a marine paleoenvironment during early Holocene sea level rise. Journal of Quaternary Science 34, 581–592.
- Hepp, D.A., Warnke, U., Hebbeln, D. & Mörz, T. 2017: Tributaries of the elbe palaeovalley: features of a hidden palaeolandscape in the German bight, North Sea. Coastal Research Library 20, 211–222.
- Hjelstuen, B.O., Sejrup, H.P., Valvik, E. & Becker, L.W.M. 2018: Evidence of an ice-dammed lake outburst in the North Sea during the last deglaciation. Marine Geology 402, 118–130.
- Hornafius, J.S., Quigley, D. & Luyendyk, B.P. 1999: The world’s most spectacular marine hydrocarbon seeps (Coal Oil Point, Santa Barbara Channel, California): quantification of emissions. Journal of Geophysical Research Oceans 104, 20703–20711.
- Hovland, M., Gardner, J.V. & Judd, A.G. 2002: The significance of pockmarks to understanding fluid flow processes and geohazards. Geofluids 2, 127–136.
- Hughes, A.L.C., Gyllencreutz, R., Lohne, Ø.S., Mangerud, J. & Svendsen, J.I. 2016: The last Eurasian ice sheets – a chronological database and time-slice reconstruction, DATED-1. Boreas 45, 1–45.
- Huuse, M. & Clausen, O.R. 2001: Morphology and origin of major Cenozoic sequence boundaries in the Eastern North Sea Basin: top eocene, near-top oligocene and the mid-miocene unconformity. Basin Research 13, 17–41.
- Huuse, M., Jackson, C.A.L., Van Rensbergen, P., Davies, R.J., Flemings, P.B. & Dixon, R.J. 2010: Subsurface sediment remobilization and fluid flow in sedimentary basins: an overview. Basin Research 22, 342–360.
- Huuse, M. & Lykke-Andersen, H. 2000: Overdeepened Quaternary valleys in the eastern Danish North Sea: morphology and origin. Quaternary Science Reviews 19, 1233–1253.
- Huuse, M., Lykke-Andersen, H. & Michelsen, O. 2001: Cenozoic evolution of the eastern Danish North Sea. Marine Geology 177, 243–269.
- Jensen, J.B. & Bennike, O. 2022: Geological screening of Kattegat Area A and B. Geological seabed screening in relation to possible location of windfarm areas. Client Danish Energy Agency. GEUS, Copenhagen. Danmarks og Grønlands Geologiske Undersøgelse Rapport 2021(64).
- Judd, A. & Hovland, M. 2009: Pockmarks, shallow gas, and seeps: an initial appraisal. In: Seabed fluid flow. The impact on geology, biology and the marine environment, 7–44. Cambridge University Press, Cambridge.
- Karkov, K.H. et al. 2022: Case study: avo inversion and processing of ultra-high resolution seismic for a windfarm application. In: 83rd EAGE Annual Conference & Exhibition. European Association of Geoscientists & Engineers 2022, 1–5.
- Kirkham, J.D. et al. 2022: Tunnel valley formation beneath deglaciating mid-latitude ice sheets: observations and modelling. Quaternary Science Reviews 323, 107680.
- Klint, K.E.S. & Pedersen, S.A.S. 1995: The Hanklit glaciotectonic thrust fault complex, Mors, Denmark. Danmarks Geologiske Undersøgelse, Serie A 35, 1–30.
- Knudsen, K.L. & Sejrup, H.P. 1993: Pleistocene stratigraphy in the Devils Hole Area, Central North Sea: foraminiferal and amino–acid evidence. Journal of Quaternary Science 8, 1–14.
- Knutz, P.C. 2010: Channel structures formed by contour currents and fluid expulsion: significance for late neogene development of the central north sea basin. Petroleum Geology Conference Proceedings 7, 77–94.
- Knutz, P.C., Rasmussen, E.S., Laghari, S. & Prins, L.T. 2022: A desk study of the geological succession below a proposed energy island. Danish North Sea Report prepared for EnergiNet.
- Larsen, B. & Andersen, L.T. 2005: Late quaternary stratigraphy and morphogenesis in the Danish eastern North Sea and its relation to onshore geology. Netherlands Journal of Geosciences 84, 113–128.
- Le, T.M.H., Eiksund, G.R., Strøm, P.J. & Saue, M. 2014: Geological and geotechnical characterisation for offshore wind turbine foundations: a case study of the Sheringham Shoal wind farm. Engineering Geology 177, 40–53.
- Le Bot, S., Van Lancker, V., Deleu, S., De Batist, M., Henriet, J.P. & Haegeman, W. 2005: Geological characteristics and geotechnical properties of Eocene and Quaternary deposits on the Belgian continental shelf: synthesis in the context of offshore wind farming. Netherlands Journal of Geosciences 84, 147–160.
- Leth, J.O. 1996: Late Quaternary geological development of the Jutland Bank and the initiation Jutland Current, NE North Sea. Geological Survey of Norway Bulletin 430, 25–34.
- Lohrberg, A., Schmale, O., Ostrovsky, I., Niemann, H., Held, P. & Schneider von Deimling, J. 2020: Discovery and quantification of a widespread methane ebullition event in a coastal inlet (Baltic Sea) using a novel sonar strategy. Scientific Reports 10, 1–14.
- Lonergan, L., Maidment, S.C.R. & Collier, J.S. 2006: Pleistocene subglacial tunnel valleys in the central North Sea basin: 3-D morphology and evolution. Journal of Quaternary Science 21, 891–903.
- Mellett, C.L., Phillips, E., Lee, J.R., Cotterill, C.J., Tjelta, T.I., James, L. & Duffy, C. 2020: Elsterian ice-sheet retreat in the southern North Sea: antecedent controls on large-scale glaciotectonics and subglacial bed conditions. Boreas 49, 129–151.
- Møllgaard, P., Halkier, B., Kristensen, N.B., Bye, B., Helselberg, P., Knudsen, M.T., Münster, M., Richardson, K. & Thorsen, B.J. 2024: Status Outlook 2024. The Danish Council on Climate Change, Copenhagen.
- Mooney, T.A., Andersson, M. & Stanley, J. 2020: Acoustic impacts of offshore wind energy on fishery resources: an evolving source and varied effects across a wind farm’s lifetime. Oceanography 33, 82–95.
- Moreau, J. & Huuse, M. 2014: Infill of tunnel valleys associated with landward-flowing ice sheets: the missing middle pleistocene record of the NW European rivers? Geochemistry, Geophysics, Geosystems 15, 1–9.
- Moss, J.L., Cartwright, J. & Moore, R. 2012: Evidence for fluid migration following pockmark formation: examples from the Nile Deep Sea Fan. Marine Geology 303–306, 1–13.
- Nielsen, T., Mathiesen, A. & Bryde-Auken, M. 2008: Base quaternary in the Danish parts of the North Sea and Skagerrak. Geological Survey of Denmark and Greenland Bulletin 15, 37–40.
- Noble-James, T., Judd, A., Diesing, M., Clare, D., Eggett, A., Silburn, B. & Duncan, G. 2020: Monitoring shallow methane-derived authigenic carbonate: insights from a UK Marine Protected Area. Aquatic Conservation Marine and Freshwater Ecosystems 30, 959–976.
- Nørgaard-Pedersen, N. & Rödel, L.G. 2021: Slutopmåling af auktionsområde 562-LD. Jyske Rev. Kortlægning og miljøvurdering for Thyborøn Nordsøral A/S. Danmarks og Grønlands Geologiske Undersøgelse Rapport 42, 59 pp.
- Ottesen, D., Dowdeswell, J.A. & Bugge, T. 2014: Morphology, sedimentary infill and depositional environments of the Early Quaternary North Sea Basin (56°–62°N). Marine and Petroleum Geology 56, 123–146.
- Owen, M., Bodin, S., Andresen, K.J. & Al-hamdani, Z. 2021: Investigating Pockmark Fields in the Danish Skagerrak. Danish Rnvironmental Agency Report 2190, pp 27.
- Owen, M., Knutz, P. & Prins, L.T. 2020: En geologisk screeningundersøgelse af potentielle energiøområder i Dansk Nordsø. Rapport udført for Energistyrelsen. Danmarks og Grønlands Geologiske Undersøgelse Rapport 24, 50 pp.
- Pedersen, S.A.S. & Boldreel, L.O. 2017: Glaciotectonic deformations in the Jammerbugt and glaciodynamic development in the eastern North Sea. Journal of Quaternary Science 32, 183–195.
- Petersen, H.I. & Smit, F.W.H. 2023: Application of mud gas data and leakage phenomena to evaluate seal integrity of potential CO2 storage sites: a study of chalk structures in the Danish Central Graben, North Sea. Journal of Petroleum Geology 46, 47–75.
- Petrie, H.E., Eide, C.H., Haflidason, H., Brendryen, J. & Watton, T. 2024: An integrated geological characterization of the Mid-Pleistocene to Holocene geology of the Sørlige Nordsjø II offshore wind site, southern North Sea. Boreas 53, 186–226.
- Petrie, H.E., Eide, C.H., Haflidason, H. & Watton, T. 2022: A conceptual geological model for offshore wind sites in former ice stream settings: the Utsira Nord site, North Sea. Journal of the Geological Society 179, jgs2021-163.
- Phillips, E., Hodgson, D.M. & Emery, A.R. 2017: The quaternary geology of the North Sea basin. Journal of Quaternary Science 32, 117–126.
- Prins, L.T. & Andresen, K.J. 2019: Buried late Quaternary channel systems in the Danish North Sea – Genesis and geological evolution. Quaternary Science Reviews 223, 105943.
- Prins, L.T. & Andresen, K.J. 2021: A geotechnical stratigraphy for the shallow subsurface in the Southern Central Graben, North Sea. Engineering Geology 286, 106089.
- Prins, L.T., Andresen, K.J., Clausen, O.R. & Piotrowski, J.A. 2020: Formation and widening of a North Sea tunnel valley – the impact of slope processes on valley morphology. Geomorphology 368, 107347.
- Rank-Friend, M. & Elders, C.F. 2004: The evolution and growth of Central Graben salt structures, Salt Dome Province, Danish North Sea. Geological Society, London, Memoirs 29, 149–164.
- Rea, B.R. et al. 2018: Extensive marine-terminating ice sheets in Europe from 2.5 million years ago. Science Advances 4, eaar8327.
- Reusch, A. et al. 2015: Giant lacustrine pockmarks with subaqueous groundwater discharge and subsurface sediment mobilization. Geophysical Research Letters 42, 3465–3473.
- Rijsdijk, K.F., Passchier, S., Weerts, H.J.T., Laban, C., van Leeuwen, R.J.W. & Ebbing, J.H.J. 2005: Revised Upper Cenozoic stratigraphy of the Dutch sector of the North Sea Basin: towards an integrated lithostratigraphic, seismostratigraphic and allostratigraphic approach. Netherlands Journal of Geosciences 84, 129–146.
- Stewart, M.A., Lonergan, L. & Hampson, G. 2013: 3D seismic analysis of buried tunnel valleys in the central North Sea: morphology, cross-cutting generations and glacial history. Quaternary Science Reviews 72, 1–17.
- Van der Vegt, P., Janszen, A. & Moscariello, A. 2012: Tunnel valleys: current knowledge and future perspectives. Geological Society, London, Special Publications 368, 75–97.
- Velenturf, A.P.M., Emery, A.R., Hodgson, D.M., Barlow, N.L.M., Mohtaj Khorasani, A.M., Van Alstine, J., Peterson, E.L., Piazolo, S. & Thorp, M. 2021: Geoscience solutions for sustainable offshore wind development. Earth Science Systems and Society 1, 1–23.
- Vielstädte, L., Karstens, J., Haeckel, M., Schmidt, M., Linke, P., Reimann, S., Liebetrau, V., McGinnis, D.F. & Wallmann, K. 2015: Quantification of methane emissions at abandoned gas wells in the Central North Sea. Marine and Petroleum Geology 68, 848–860.
- Walter Anthony, K.M., Anthony, P., Grosse, G. & Chanton, J. 2012: Geologic methane seeps along boundaries of Arctic permafrost thaw and melting glaciers. Nature Geoscience 5, 419–426.
- Watts, R., Lee, A. & Snieckus, D. 2021: Saipem woe as ‘soil and foundations’ issues hit work on North Sea wind farm installation. UpStream. https://www.upstreamonline.com/energy-transition/saipem-woe-as-soil-and-foundations-issues-hit-work-on-north-sea-wind-farm-installation/2-1-971065 (accessed Feb 2025).
- Winsemann, J., Koopmann, H., Tanner, D.C., Lutz, R., Lang, J., Brandes, C. & Gaedicke, C. 2020: Seismic interpretation and structural restoration of the Heligoland glaciotectonic thrust-fault complex: implications for multiple deformation during (pre-)Elsterian to Warthian ice advances into the southern North Sea Basin. Quaternary Science Reviews 227, 106068.
- Ziegler, P.A. 1992: North Sea rift system. In: Ziegler, P.A. (ed.): Geodynamics of rifting, volume I. Case history studies on rifts: Europe and Asia. Tectonophysics 208, 55–75.