The map is based on selected seismic data up to 2001. The map shows the structural conditions at depth for the 'Top Kalk' surface, from the central to the eastern part of the Danish North Sea. 'Top Kalk' denotes the surface which forms the basis of the Tertiary deposits (except Denmark). The map is described in GEUS Bulletin No. 13. 2007.

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.

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 geologist and will be augmented through more information forthcoming through GEUS and company activities. Only data released to the public will be available to external users over the internet.

Samples of surface material, i.e. stream sediment, soil, and scree have been collected over large parts of Greenland from 1974 onwards mainly as part of mineral exploration programmes and more broadly for geochemical mapping by means of stream sediment (Steenfelt 1999, 2001). Following various sample preparation procedures, like drying and screening, making concentrates of heavy minerals from stream sediment or soil, certain fractions of the samples have been chemically analysed at diverse laboratories where a range of analytical methods were applied as they became available over the years. The present dataset contains the analytical data from soil samples as they were received from the laboratories together with administrative data, including sample location and grain-size fraction analysed. Many samples have been analysed at more than one laboratory and by more than one method and the analytical data for each sample and grain size fraction are listed lab by lab and method by method in the same row. Five samples are used in the Geochemical Atlas of Stream sediment samples of South-West Greenland (Steenfelt, 1999). 204 samples from North Greenland have been used in the Geochemical Atlas of Stream sediment samples for North Greenland (Thrane 2011). In addition soil samples were collected in the SEGMENT project (Kolb et al. 2016)

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.

In the present database there are 1269 unique samples. Soil samples have been collected in areas without river beds. Preferably stream samples have been collected, but areas where temporarily no stream beds are present, soil samples have been collected as an alternative for geochemical mapping purpose. Five samples in this package are originally from the report Compilation of data sets for a geochemical Atlas (Steenfelt, 1999). These samples have been analysed by "UNKNOWN" methods at "UNKNOWN" laboratories. In fact these samples have been calibrated and corrected for analytical bias, see Steenfelt 1999, for further information.

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.

Each map displays a grid image of the variation in element concentration, a colour scale giving class intervals for the grid colours, histograms showing the frequency distributions of sample values and grid cell values, respectively, and statistical parameters for measured concentrations in samples and for the grid cell values. All element concentrations below the lower limit of detection for the analytical method have been set to zero for simplicity, and in accordance with their registration in the GEUS database. Major element oxide concentrations have been recalculated as volatile-free concentrations to compensate for the effect of variable contents of organic matter and carbonate.

Zircon age data as gathered from literature and GEUS samples

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.