The regional-scale gamma spectrometry data are associated with two collaboration projects involving the Geological Survey of Greenland (GGU) and the Danish Atomic Energy Commission’s Research Establishment. The projects' objectives were to outline areas with an elevated uranium potential in two regions of Greenland: The airborne radiometric surveys in southern and central West Greenland in 1975/76 and the SYDURAN project in South Greenland in 1979-1982. To acquire the data, four-channel gamma ray spectrometers were mounted upon an aircraft (1975/76 surveys) and a helicopter (SYDURAN project). The vehicles flew along shoreline and valley contour lines at low average terrain clearances of 100 and 50 m respectively. The data were recorded without GPS systems, and so positioning was estimated when known landmarks were passed. This means that the dataset is sparse and inhomogeneous, and the spatial accuracy remains low. The gamma-spectrometer had been calibrated at a pad facility at Risø, which enabled the conversion of recorded counts per second into simulated concentrations of radioactive components in the surface of the overflown terrain. Large parts of the data (surveys from 1975/76) were originally stored on magnetic tapes and data were transferred to datafiles in 2003 to make them digital accessible. Most data were retrieved and are now available as ASCII files.

Zircon age data as gathered from literature and GEUS samples

Exploration companies are obliged to report their activities to the Ministry of Minerals and Resources (MMR). Now reports are delivered in digital format, but were previously delivered in paper, to the Geological Survey of Denmark and Greenland (GEUS). They are scanned and released reports are available under Reports. Digital restoration The data that the reports hold is thus available, but stored as images in scanned pdf?s. The geochemical data of 4 reports (Allen & Harris, 1980; Coppard et al., 1992; Harris et al., 1992 and Pearson & Joudrie, 1995) have been digitized. I.e. the reports have be optically characterised and the sample locations georeferenced. The matching of the sample locations and geochemically referenced samples does not always match. Meaning that a sample that has coordinate may not have geochemical results, and a sample with geochemical measurements might not have coordinate. The reporting of the analytical facilities and precision is sparse. Detection limits, analytical uncertainty and reliability are generally not reported. Analytical methods and analysed grain fractions of sediment samples also not reported. When all these issues have been listed, it should be noted that errors may occur. From the digital restoration of scanned paper to optically characterisation of the scanned text and numbers errors may be introduced. The user is cautioned to these issues. Upload to data base To make the data available on the web, upload to GEUS sample data base is required. To fit into the sample data base, some adjustments had to be made. Sample names modified, collector created etc., resulting in modified sample names, relative to the ones used in the reports. The reports from which the samples occur in are not mentioned in the data base. Hence the four reports and links to them are listed below:

The geological maps of Denmark on a scale of 1:400,000 focus on the Danish basin and its geological structures. The map includes areas that extend from the geological age 'Basis Kalk' and the Kalk Gruppen. The 'Basis Kalk' map shows the depth in metres, where 'Basis Kalk' denotes the area that forms the basis for all layers younger than the Early Cretaceous. Over the majority of the mapped area, this surface is level with the base of the Kalk Group, but where the limestone is eroded away, the surface is equal to the base of the Quaternary. The depth to 'Basis Kalk' is calculated as the depth to the base of the deposits younger than Denmark plus the thickness of the Kalk group. The map is published in DGU Map Series no. 29 from 1991, where further information about the mapping can be obtained.

A series of Aster band ratios highlighting mineral distributions. Band ratio color composite images to distinguish variability of lithology in the area. Preprocessing of the Aster scenes encompasses atmospheric, radiometric and topographic corrections before masking non-outcrop pixels and generating the final mosaic. The calibrated radiance data is converted to apparent surface reflectance using a radiative transfer program, Atmospheric and Topographic Correction (ATCOR-3), in rugged terrain mode. The ATCOR rugged terrain mode utilizes a surface elevation model to adjust illumination levels. Calibration and adjusting the apparent surface reflectance values from the ATCOR-3 processing was not feasible due to lack of ground-based reflectance measurements.

The place names data set is from the book 'Northern East Greenland's research history and place names' by A.K. Higgins, which GEUS published in 2010, with associated maps which have now been converted to web GIS format. Via free text search, you can find the place names with their explanations and their location on the map.

The Raw stream sediment samples dataset is data as they have been delivered from the laboratories, i.e. values below detection limit often spelled as negative but zero may also apply. The data are not controlled by a geologist. In addition, they may not have been reported.

Historical mineral exploration and exploitation licences in Greenland. The data are converted from the WFS that the ministery of mineral resources (MMR) in Greenland provides. Links are provided in the online resources.

Ujarassiorit is a mineral hunt competition open to residents of Greenland. Participants can submit rock samples from Greenland to the Ministry of Minerals Ressources (MMR) for evaluation and may be selected for a prize.

This repository contains maps of the thickness of late glacial and Holocene deposits in the Danish sea area, prepared as a basis for planning offshore wind. These are unconsolidated sediments that have not been overrun by the ice sheets of the ice ages, and therefore may have low geotechnical strength parameters. This is a large-scale and very general mapping, and no detailed interpretation of the distribution of sand and clay/mud/silt, respectively, has been made. In relation to the foundations of offshore wind turbines, sandy deposits will typically not pose a challenge, while soft deposits of clay, mud and silt in large thicknesses are assumed to pose foundation challenges. In addition to separate maps of the thickness of late glacial and Holocene deposits, a map of the total thickness of these two units has also been prepared, which thus constitutes a map of the total thickness of potentially soft sediments. Finally, the thickness of potentially soft sediments is used to divide the Danish sea area into categories in relation to the probability of larger thicknesses of soft sediments that could give rise to foundation challenges. Other maps are the thickness of potentially soft glacial lake sediments in the North Sea, the depth to the Pre-Quaternary surface in the waters around Bornholm, as well as the depth to the base of the Holocene deposits and the depth to the base of the late glacial deposits/top of the glacial deposits in the Danish sea area. As a supplement to the maps, a number of themes show where the late glacial and Holocene deposits are primarily expected to consist of sandy sediments. In addition, a number of themes show the Danish exclusive economic zone (EEZ), the location of conceptual geological models that can be seen in the overall report, all interpreted seismic lines, areas with near-surface gas in the sediments, interpreted distribution of the Palaeo-Elbe Valley in the North Sea, distribution of the Weichsel ice and ice-affected sediments in the North Sea, buried valleys (Prins & Andresen 2019; van der Vegt et al. 2012; Ottesen et al. 2020; Kirkham et al. 2024; Sandersen & Jørgensen 2016), structural elements (Al Hseinat & Hübscher 2017; Jensen et al. 2002), ice margin lines (Lange 1984; Kjær et al. 2003; Pedersen 2005; Phillips et al. 2018, 2022; Kirkham et al. 2024; Szuman et al. 2024; Pedersen & Boldreel 2017). The data basis for the work has primarily been new and existing near-surface seismic data and vibrocore drilling. The mapping was carried out for the Danish Energy Agency by GEUS, and is intended to support the development of offshore wind. The results, together with a sensitivity mapping of natural and environmental parameters, initiated by the Danish Energy Agency, are to be included in an overall assessment of suitable areas for offshore wind in Denmark. The documentation includes appendices: Better geological data for developing offshore wind - Overall geological mapping of the Danish sea area for the Danish Energy Agency. Appendix report. Geological Survey of Denmark and Greenland Report 2025/29. Vangkilde-Pedersen, T., Christensen, N., Nørgaard-Pedersen, N., Allaart, L., Bennike, O., Leth, J.O., Winther, L.H., Sandersen, P.B.E., Prins, L.T., Singhroha, S. & Pérez, L.F. 2025. Better geological data for developing offshore wind. Overall geological mapping of the Danish sea area for the Danish Energy Agency. Geological Survey of Denmark and Greenland Report 2025/29. 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. https://doi.org/10.1016/j.quascirev.2019.105943 van der Vegt, P., Janszen, A. & Moscariello, A. 2012: Tunnel valleys: Current knowledge and future perspectives. In: Huuse, M., Redfern, J., Le Heron, D.P., Dixon, R., Moscariello, A. & Craig, J. (eds): Glaciogenic reservoirs and hydrocarbon systems. Geological Society, Special Publications, London 368, 75–97. https://doi.org/10.1144/sp368.13 Ottesen, D., Stewart, M., Brönner, M. & Batchelor, C.L. 2020: Tunnel valleys of the central and northern North Sea (56◦N to 62◦N): distribution and characteristics. Marine Geology 425, 106199. https://doi.org/10.1016/j.margeo.2020.106199 Kirkham, J.D., Hogan, K.A., Larter, R.D., Self, E., Games, K., Huuse, M., Stewart, M.A., Ottesen, D., Le Heron, D.P., Lawrence, A., Kane, I., Arnold, N.S. & Dowdeswell, J.A. 2024: The infill of tunnel valleys in the central North Sea: Implications for sedimentary processes, geohazards, and ice-sheet dynamics. Marine Geology 467, 107185. https://doi.org/10.1016/j.margeo.2023.107185 Sandersen, P.B.E. & Jørgensen, F. 2016: Kortlægning af begravede dale i Danmark. Opdatering 2015. GEUS Særudgave, december 2016, bind 1 og 2. https://www.begravededale.dk/PDF_2015/091116_Rapport_Begravede_dale_BIND_1_Endelig_udgave_Low_res.pdf Al Hseinat, M. & Hubscher, C. 2017: Late Cretaceous to recent tectonic evolution of the north German Basin and the transition zone to the Baltic Shield/Southwest Baltic Sea. Tectonophysics 708, 28–55. https://doi.org/10.1016/j.tecto.2017.04.021 Jensen, J.B. & Bennike, O. 2022: Geological Screening of Kriegers Flak North and South. Geological seabed screening in relation to possible location of windfarm areas. GEUS Rapport 2022/2. https://doi.org/10.22008/gpub/34637 Lange, D., 1984: Geologische Untersuchungen an spätglazialen und holozänen Sedimenten der Lübecker und Mecklenburger Bucht. Unveröffentlichte Dissertation (B), Institut für Meereskunde Warnemünde, 166 S. Kjær, K.H., Houmark-Nielsen, M., Richardt, N. 2003: Ice-flow patterns and dispersal of erratics at the southwestern margin of the last Scandinavian ice sheet: signature of palaeo-ice streams. Boreas 32: 130–148. https://doi.org/10.1111/j.1502-3885.2003.tb01434.x Pedersen, S.A.S. 2005: Structural analysis of the Rubjerg Knude Glaciotectonic Complex, Vendsyssel, northern Denmark. Geological Survey of Denmark and Greenland Bulletin 8, 192 pp. https://doi.org/10.34194/geusb.v8.5253 Phillips, E., Cotterill, C., Johnson, K., Crombie, K., James, L., Carr, S. & Ruiter, A. 2018: Large-scale glacitectonic deformation in response to active ice sheet retreat across Dogger Bank (southern central North Sea) during the Last Glacial Maximum. Quaternary Science Reviews 179, 24-47. https://doi.org/10.1016/j.quascirev.2017.11.001 Phillips, E., Johnson, K., Ellen, R., Plenderleith, G., Dove, D., Carter, G., Dakin, N. & Cotterill, C. 2022: Glacitectonic evidence of ice sheet interaction and retreat across the western part of Dogger Bank (North Sea) during the Last Glaciation. Proceedings of the Geologists' Association 133, 87-111. https://doi.org/10.1016/j.pgeola.2021.11.005 Szuman, I., Kalita, J. Z., Diemont, C. R., Livingstone, S. J., Clark, C. D., and Margold, M. 2024: Reconstructing dynamics of the Baltic Ice Stream Complex during deglaciation of the Last Scandinavian Ice Sheet, The Cryosphere, 18, 2407–2428. https://doi.org/10.5194/tc-18-2407-2024. 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. https://doi.org/10.1002/jqs.2887