This data set contains a bed topography and bathymetry map of Greenland based on mass conservation, multi-beam data, and other techniques. It also includes surface elevation and ice thickness data, as well as an ice/ocean/land mask.

Geology is based on field work by Peter R. Dawes in 1971, 1975 and 1978, the latter year with Allen P. Nutman. Compiled with photointerpretation 1988–89, with local revision based on field work in 2001. Apart from northernmost Kangerlussuaq (Inglefield Bredning), the coast was surveyed by boat with sporadic foot traverses, aided by helicopter in 1978 and 2001. Geology of Qaqujaarsuaq (Smithson Bjerge) is based on simplification of the 1:50 000 map by Allen P. Nutman (1984). GIS compilation: Katja T. Walentin, Samuel P. Jackson, Eva Willerslev and Mette S. Jørgensen. Cross sections: Martin Sønderholm; Smithson Bjerge section is based on Nutman (1984). Editorial handling: Thomas F. Kokfelt and Martin Sønderholm. Reviewed by John Grocott (Durham University, United Kingdom) and Marc R. St-Onge (Geological Survey of Canada). Detailed information on the map units is available in the GEUS Greenland Intrusive and Stratigraphic Database using the GU-codes shown in brackets in the legend (https://doi.org/10.22008/FK2/F9MBNJ). Information on mineral occurrences is available in the Greenland Mineral Resources Portal (https://www.greenmin.gl). Topographic base: Geodetic Institute maps at 1:200 000 from 1954 with major revision of the ice margin and glaciers based on 1:150 000 aerial photographs from 1985–1987 and Sentinel 2 satellite scenes from 2019. All heights are in metres. Additional lake heights are from the Danish Agency for Data Supply and Infrastructure (now the Danish Agency for Climate Data): Højdemodel Grønland (https://dataforsyningen.dk/data/4780, accessed September 2023). Ground exposed by ice retreat since initial compilation in 1988–1989 is identified in the legend. 1949 ice margins are from Geodetic Institute maps. Ice margins recorded during expeditions by Robert E. Peary in 1892 and Lauge Koch in 1922 are approximate. Ice altimetry and thickness are based on data from Morlighem et al. (2017), bathymetry is from Morlighem et al. (2022). Authorised place names are from Oqaasileriffik (The Language Secretariat of Greenland), with supplementary names from Laursen (1972). Projection: WGS 84 UTM Zone 20N. Copyright © Geological Survey of Denmark and Greenland. References: Dawes, P.R. 1997: The Proterozoic Thule Supergroup, Greenland and Canada: history, lithostratigraphy and development. Geology of Greenland Survey Bulletin 174, 150 pp. https://doi.org/10.34194/ggub.v174.5025 Dawes, P.R. 2006: Explanatory notes to the Geological map of Greenland, 1:500 000, Thule, Sheet 5. Geological Survey of Denmark and Greenland Map Series 2, 97 pp. + map sheet. https://doi.org/10.34194/geusm.v2.4614 Laursen, D. 1972: The place names of North Greenland. Meddelelser om Grønland 180(2), 443 pp. + 18 plates. Morlighem, M. et al. 2017: BedMachine v3 [Surface; Thickness]: Complete bed topography and ocean bathymetry mapping of Greenland from multibeam echo sounding combined with mass conservation. Geophysical Research Letters 44, 11051–11061. https://doi.org10.1002/2017GL074954 Morlighem, M. et al. 2022: IceBridge BedMachine Greenland, Version 5 [Bed]. NASA National Snow and Ice Data Center Distributed Active Archive Center. https://doi.org/10.5067/GMEVBWFLWA7X (accessed January 2024). Nutman, A.P. 1984: Precambrian gneisses and intrusive anorthosite of Smithson Bjerge, Thule district, North-West Greenland. Rapport Grønlands Geologiske Undersøgelse 119, 31 pp. + plate. https://doi:10.34194/rapggu.v119.7849 Thomassen, B. & Krebs, J.D. 2004: Mineral exploration of selected targets in the Qaanaaq region, North-West Greenland: follow-up on Qaanaaq 2001. Danmarks og Grønlands Geologiske Undersøgelse Rapport 2004/42, 64 pp. https://doi.org/10.22008/gpub/25622 Thomassen, B., Krebs, J.D. & Dawes, P.R. 2002: Qaanaaq 2001: mineral exploration in the Olrik Fjord – Kap Alexander region, North-West Greenland. Danmarks og Grønlands Geologiske Undersøgelse Rapport 2002/86, 72 pp. + map. https://doi.org/10.22008/gpub/18491

Geology is based on field work by Peter R. Dawes in 1971, 1975 and 1978. Compiled with photointerpretation 1988–89, with local revision based on field work in 2001. The coast was surveyed by boat with sporadic foot traverses, aided by helicopter in 1978 and 2001. GIS compilation: Katja T. Walentin, Samuel P. Jackson, Eva Willerslev and Mette S. Jørgensen. Cross section: Martin Sønderholm. Editorial handling: Thomas F. Kokfelt and Martin Sønderholm. Reviewed by John Grocott (Durham University, United Kingdom) and Marc R. St-Onge (Geological Survey of Canada). Detailed information on the map units is available in the GEUS Greenland Intrusive and Stratigraphic Database using the GU-codes shown in brackets in the legend (https://doi.org/10.22008/FK2/F9MBNJ). Information on mineral occurrences is available in the Greenland Mineral Resources Portal (https://www.greenmin.gl). Topographic base: Geodetic Institute maps at 1:200 000 from 1954 with major revision of the ice margin and glaciers based on 1:150 000 aerial photographs from 1985–1987 and Sentinel 2 satellite scenes from 2019. All heights are in metres. Additional lake heights are from the Danish Agency for Data Supply and Infrastructure (now the Danish Agency for Climate Data): Højdemodel Grønland (https://dataforsyningen.dk/data/4780, accessed September 2023). Ground exposed by ice retreat since initial compilation in 1988–1989 is identified in the legend. 1949 ice margins are from Geodetic Institute maps. Ice margins recorded during expeditions by Robert E. Peary in 1892 and Lauge Koch in 1922 are approximate. Ice altimetry and thickness are based on data from Morlighem et al. (2017), bathymetry is from Morlighem et al. (2022). Landslides are modified from GEUS internal data, for methodology see Svennevig (2019). Authorised place names are from Oqaasileriffik (The Language Secretariat of Greenland), with supplementary names from Laursen (1972). Projection: WGS 84 UTM Zone 20N. Copyright © Geological Survey of Denmark and Greenland. References: Dawes, P.R. 1997: The Proterozoic Thule Supergroup, Greenland and Canada: history, lithostratigraphy and development. Geology of Greenland Survey Bulletin 174, 150 pp. https://doi.org/10.34194/ggub.v174.5025 Dawes, P.R. 2006: Explanatory notes to the Geological map of Greenland, 1:500 000, Thule, Sheet 5. Geological Survey of Denmark and Greenland Map Series 2, 97 pp. + map sheet. https://doi.org/10.34194/geusm.v2.4614 Laursen, D. 1972: The place names of North Greenland. Meddelelser om Grønland 180(2), 443 pp. + 18 plates. Morlighem, M. et al. 2017: BedMachine v3 [Surface; Thickness]: Complete bed topography and ocean bathymetry mapping of Greenlandfrom multibeam echo sounding combined with mass conservation. Geophysical Research Letters 44, 11051–11061. https://doi.org/10.1002/2017GL074954 Morlighem, M. et al. 2022: IceBridge BedMachine Greenland, Version 5 [Bed]. NASA National Snow and Ice Data Center Distributed Active Archive Center. https://doi.org/10.5067/GMEVBWFLWA7X (accessed January 2024). Svennevig, K. 2019: Preliminary landslide mapping in Greenland. Geological Survey of Denmark and Greenland Bulletin 43,e2019430207. https://doi.org/10.34194/GEUSB-201943-02-07 Thomassen, B., Krebs, J.D. & Dawes, P.R. 2002: Qaanaaq 2001: mineral exploration in the Olrik Fjord – Kap Alexander region, North-West Greenland. Danmarks og Grønlands Geologiske Undersøgelse Rapport 2002/86, 72 pp. + map. https://doi.org/10.22008/gpub/18491

The Nippon Foundation-GEBCO Seabed 2030 project has produced a global terrain model for ocean and land. The GEBCO_2023 grid was published in April 2023 and is the fifth GEBCO grid developed through The Nippon Foundation-GEBCO Seabed 2030 Project. This is a collaborative project between the Nippon Foundation of Japan and GEBCO. The Seabed 2030 Project aims to bring together all available bathymetric data to produce the definitive map of the world ocean floor and make it available to all.

The GEBCO_2023 Grid is a continuous, global terrain model for ocean and land with a spatial resolution of 15 arc seconds. Between latitudes of 50° South and 60° North it uses version 2.5.5 of the SRTM15+ dataset as a \"base\". This data set is a fusion of land topography with measured and estimated seafloor topography. This version of SRTM15+ is similar to version 2.1 [Tozer et al., 2019] but includes additional data sets. It uses predicted depths based on the V32 gravity model [Sandwell et al., 2019]. The SRTM15+ base grid has been augmented with the gridded bathymetric data sets developed by the four Seabed 2030 Regional Centers to produce the GEBCO_2023 Grid. Note: SRTM15+ V2.5.5 is also available through OpenTopography here.

The information for ice-surface elevation and under-ice topography/bathymetry is taken from IceBridge BedMachine Greenland, Version 4.6 (Morlighem, M. et al. 2017) and data based on MEaSUREs BedMachine Antarctica, Version 2 (Morlighem, M. et al 2020).

NOTE: This dataset includes under-ice sheet topography. For a version of the dataset with ice surface topography see \"GEBCO IceTopo\" below under \"Other Available Data Products\".