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    The dataset contains outlines of archived historical unpublished geological maps and sections of Greenland mostly created by GGU and GEUS but also some other institutes from 1916 onwards at various scales.

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    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.

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    Intrusions and magmatic complexes are central, when it comes to an assessment of the economic geological potential of a region. There are many of these in Greenland, and only a few of them have been examined in detail for their economic potential. In Nielsen (2002), tertiary intrusions and complexes in East Greenland were described, and later on information on intrusions and magmatic complexes in all of Greenland, were modelled based on the same methodology. The information has been compiled by GEUS geologists.

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    The digital terrain model of Greenland is constructed on the basis of GEUS's topographic datasets from the official geological maps of Greenland in scale ratio 1:100.000 and 1:500.000. The DEM is created using an interpolation method called Topo to Raster function in ArcGIS Desktop which is primarily supported by contour lines, coastlines and elevation points. The creation of the DEM was divided into in sub-areas based on the map sheet frames from the geological map of Greenland in 1:500.000 scale and assembled as a raster mosaic. The DEM was created with the spatial coordinate reference system WGS 1984 / UTM Zone 24N Complex with a resolution of a 100x100 meter grid. Based on the final DEM, a hillshade efect of the terrain has been constructed.

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    Greenland mineral assessment workshops have been held on Sedimentary-hosted Copper, type: redbed-, revett- and reduced-facies type in 2009, Various Rare Earth Elements deposit types in 2010 (this workshop was not carried out according to the 'three-part quantitative assessment' method), Sedimentary-hosted zinc SEDEX- and MVT-type in 2011, Magmatic nickel; komatiite-hosted, contact- and conduit-type in 2012 and Vein- and skarn type Tungsten in 2013 and Orogenic gold type in 2014. Most of the workshops, besides the one on rare earth elements, have been following the processes and methodologies used in the 'three-part quantitative assessment' method of the U.S. Geological Survey described by Singer (1993). The method does not define deposits or provide mineral resource or reserve estimates according to industrial or international recognised certified standards. The objective is to produce a probabilistic estimate of unknown/undiscovered deposits and corresponding probabilistic estimates of the total amount of metals down to one kilometre depth. The estimates do not take into account economic, technical, social or environmental factors. In the 'three-part quantitative assessment' method, an expert panel reviewed and discussed all available knowledge and data for a specific region (Tract) to assess the possibility of finding new undiscovered deposits within this Tract. The expert panels consisted of geologists from universities, research institutions, Surveys as well as private exploration and mining companies. The experts have either expertise in/worked with the deposit type in focus, with the regional and/or local geology relevant for the tracts being assessed or have expertise from exploration/mining projects for the deposit type in focus elsewhere in the world. One or two international top-experts on the mineral deposit type in focus for the different workshops have also participated in the workshop. After reviewing the available knowledge and data the members of the panel made their individual estimates (bids) of the number of undiscovered deposits they believed could be found under the best circumstances in a tract. The bids are based on the characteristics derived from descriptive mineral deposit models and a number of key-literature on the mineralisation type. In several of the workshops, critical elements have also been considered in the mineralising system (e.g. McCuaig & Hronsky 2014) associated with the deposit type in focus, when carrying out the bids. A panel discussion of the bids led to a consensus bid, which was used as input to a statistical Monte Carlo simulation. Based on established grade-/tonnage models of e.g. known tungsten deposits worldwide, this simulation can provide a prediction on how much undiscovered metals could be found within a Tract. The 'Tracts' are spatial polygons that define a certain area that was found to be permissive for the concerned mineral deposit type and which constitutes the same level of geology, knowledge and data coverage. Tracts are named with a unique name, tract area is given in square kilometre and consensus bids from team under N90, N50, N10, N05 and N01 headings of undiscovered metals deposits at different confidence levels. The statistics from the Monte Carlo simulation is shown under the headings Numbers of unknown deposits and Deposit density.

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    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.

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    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.

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    The Atlas samples of N Greenland package are described in Thrane et al 2011. This package builds on samples collected over a period from 1978 to 1999, holding old and newly acquired data. Some of the old samples have been reanalysed and together they have been quality controlled and compared. There are 2,644 unique samples in this package (65 of these samples are located under Soil samples). The geochemical analyses that are presented are above detection limit and readings below have been filtered out. Sampling The sampling density is not consistent throughout the covered area, and varies from 1 sample per 30 to 50 km2 to scarce and irregular in other areas. The regional geochemical surveys undertaken in North Greenland, follows the procedure for stream sediment sampling in Steenfelt, 1999. Thrane et al 2011, give more information sampling campaigns in the area. The sample consists of 500 g sediment collected from stream bed and banks into paper bags. In the filed the samples were dried and sent to Copenhagen for further drying and screening. Analyses was made on a split fraction < 0.1 mm size fraction.

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    The Greenland Geochronology database compiles published U-Pb geochronology from a wide range of literature sources and normalizes and recasts the data into consistent ratios and uncertainty levels; specifically all errors are given at the 1 sigma level. Importantly, this normalization provides coherence across the dataset. Additionally, ratios are verified against ages and have, if necessary, been corrected to ensure an internally consistent dataset. Systematic collation and assessment of geochronological data can be best achieved by means of a database which holds information within a structured and consistent framework which permits querying to extract relevant data and minimises difficulty in cross comparison of age information where different standards have been used.

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    The gravity compilation is based on data stored in the national/Nordic gravity data base at the DTU Space. This data base contains for Greenland data surveyed by DTU Space on behalf of the geodetic survey authorities “Danish Agency for Data Supply and Efficiency” (SDFE) and its predecessor agencies “National Survey and Cadastre” (KMS) and the Geodetic Institute (GI), with some data dating back to the 1950’s. Older data have been rectified into modern gravity datums (absolute gravimetry and IGSN71). The national data contains both surface, airborne and marine data, mainly in the coastal ice-free regions and offshore (Forsberg et al, 2001, Kenyon et al, 2008). Airborne, marine and land data from a number of external data sources are also included in the data base after a QC process, including high-level airborne data from the GAP91/92 campaigns (Brozena et al, 1993) and recent data from NASA OIB (MacGregor et al., 2021) and OMG projects (Fenty et al., 2016). Marine data in the Baffin Bay and Davis Strait and land data from the Geodetic Survey Division, Canada (Veronneau 2010, pers.comm.), and a number of other marine and land data from a large set of contributors have also been included in the compilation, including marine data from Alfred Wegener Institute (Germany), land and marine data from Orkustofnun (Iceland), and a number of released commercial data sources. In areas void of gravity data, satellite-derived altimetry data have been used as fill-in (DTU 15, Andersen et al. 2017). The compiled grids have been based on public domain and some proprietary data sources, and has been computed for the area 58-85°N, 78-7°W on a 0.02°x 0.05° grid, using rigorous downward continuation of airborne data to the terrain surface, with terrain corrections from a detailed digital terrain and ice sheet surface model, and long-wavelength satellite gravity data from GRACE and GOCE satellites (Forsberg and Olesen, 2010). The data are available as a free-air (Faye) anomaly grid as well as a derived terrain-corrected Bouguer anomaly grid (land and ice sheet areas only), computed in GRS80 with density 2.67 g/cm3. The ice sheet Bouguer anomaly data are derived using the ice sheet thickness model of Bamber et al., 2013. The free-air gravity grid (v1) have also have been used as the primary background data also for the latest geoid models of Greenland (GGEOID16).