This view presents data selected from the geochemical mapping of North Greenland that are relevant for an evaluation of the potential for zinc mineralisation: CaO, K2O, Ba, Cu, Sr, Zn. The data represent the most reliable analytical values from 2469 stream sediment and 204 soil samples collected and analysed over a period from 1978 to 1999 plus a large number of reanalyses in 2011. The compiled data have been quality controlled and calibrated to eliminate bias between methods and time of analysis as described in Thrane et al., 2011. In the present dataset, all values below lower detection limit are indicated by the digit 0. Sampling The regional geochemical surveys undertaken in North Greenland follows the procedure for stream sediment sampling given in Steenfelt, 1999. Thrane et al., 2011 give more information on sampling campaigns in the area. The sample consists of 500 g sediment collected into paper bags from stream bed and banks, alternatively soil from areas devoid of streams. The sampling density is not consistent throughout the covered area and varies from regular with 1 sample per 30 to 50 km2 to scarce and irregular in other areas. Analyses were made on screened < 0.1 mm or <0.075 mm grain size fractions.

This map is the first national map showing the depth in meters to the uppermost redox interface in sediments of Quaternary age. The redox interface indicates the transition from the oxidized to the reduced geochemical environment in sediments. The redox interface was identified according to the colors of the sediments in 11,999 wells and is shown for 1x1 km grid-cells. For grid-cells with multiple site information, the depth to the redox interface is indicated by an average value. For grid-cells without any field information, the depth of the redox interface was established based on information about 1) geological setting, 2) morphology, 3) depths to redox boundaries at nearby field sites, 4) GEUS surface geology map, 5) topography, and 6) the pre-quaternary surface. The method for this first national redox-map and the data used is described in GEUS report no. 93 (2006) entitled Beregning af nitrat-reduktionsfaktorer for zonen mellem rodzonen og frem til vandløbet. Data og metode for 1.generationskortet (in Danish). The Redox map is also described in Vand og Jord (2011) 18: 37-39 (in Danish).

Protected areas 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.

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:

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.

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.

Nationwide geophysical database for environmental and raw material data, also known as GERDA (GEophysical Relational DAtabase). The database contains various types of geophysics, including geoelectrics, electromagnetics, borehole logs and seismic. All data is freely available for download on the GEUS website. The database is updated continuously.

The Samba database contains information about geophysical investigations made in the Danish sector, acquired according to the Danish Act on the Use of the Subsoil. The data is acquired in relation to investigation for oil/gas, geothermal energy, the storage of gas or salt. That is: Seismic (2D & 3D) acquisitions, CSEM as well as other magnetic and gravity acquisitions shipborne as well as airborne. The dataset also contains geophysical measurement performed in the deep wells and meta data about the seismic surveys. The data has been submitted by the licensees. The database is updated on an ongoing basis.

The digital terrain model of Greenland is constructed on the basis of GEUS's topographic data set from the official geological maps of Greenland in scale ratios 1:100 000 and 1:500 000. The data base is primarily supported by contour lines, coastlines and support points. The terrain model is assembled as a mosaic in sub-areas based on the map sheet frames from the geological map of Greenland in 1:500 000. The terrain model is made in the coordinate system WGS 1984 Complex UTM Zone 24N with the dimensions in a 100 x 100 m grid. Based on the digital terrain model, a shadow map of the terrain has been constructed.

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.