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.

Zircon age data as gathered from literature and GEUS samples

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.

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.

Uniform aerial photographic coverage of Greenland was achieved in 1978-1987 at 1: 150 000 scale by Mark Hurd Aerial Surveys, Inc., Minneapolis, Minnesota, U.S.A., for the Danish Geodetic Institute [Weidick, 1995]. The photography is now administered by the Danish Geodata Agency, see also http://eng.gst.dk/maps-topography/greenland/aerial-photos-of-greenland. The camera used for these black and white photographs was a Wild RC 10 with a super wide angle lens (focal length = 88 cm). The airplane used by Mark Hurd was a Gates Lear Jet 25C. By setting the flying height to app. 14 km the image scale of 1:150 000 was achieved [Bengtsson & Jørgensen, 1980]. In an attempt to avoid blind areas, caused by the precipitous mountainsides in combination with the use of a super wide angle lens, the photographs were taken with a length-lap of 80%, and a side-lap of 40%. In the subsequent use of the photography (for aerotriangulation, mapping and scanning) generally only every other image were used (as you will see from the photo number shown on this web-page). The photo center coordinates are from the aerotriangulation by the Danish Geodata Agency. Please contact GST for the high resolution photos.

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)

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 Geological Survey of Denmark and Greenland has previously conducted sampling campaigns of heavy mineral concentrate in Greenland. The sampling methods are described according to their sampling years below. Unfortunately, not all the samples have reported as the campaigns in have not been undertaken on regional scale and therefore fallen under smaller projects or sampled under projects that have had other objects, and not all elements were considered relevant in the reports, translating to that metadata concerning the analyses are missing. All together there are geochemical analyses of 725 heavy mineral concentrate samples. The samples that are mentioned in reports below, are 319 in number, and do not comprise all heavy minerals samples collected the specified years. Samples collected in un-mentioned campaigns do occur in the full list. Use of data that is not mentioned here, needs caution and the quality should be weighed against other data. Years 1982-1986 A regional sampling campaign was conducted between 1982 and 1986, these samples are described in Appel 1989. These samples comprise the analysis batch numbers 10, 36 and 55. Numbers 10, 36 are analysed at Activation Laboratories and 55 analysed at Bondar-Clegg and Co. Ltd., both in Canada. In this campaign 210 samples were collected and are all sampled in the area around Nuuk. Sampling procedure: In the field: The coastal areas were accessed by boat while inland areas were accessed by helicopter. Four litres of coarse gravel and sand were collected and sieved through a 6 mesh of brass. The fines (c. 10 %) was panned and inspected in ultraviolet light and the scheelite grains counted. In the laboratory: The samples were dried and separated by bromoform, the heavy material was weighed and the scheelite grains counted again. A small splitter separated c. 0.5 gram of each sample for analysis of W, Mo, Pb, Cu, Cr, Co, V, Mn, Zr, Ni and Fe. During the years the sampling programme as well as the analysis methods changed. In 1983 the four litres were added up to five. In 1985 the material increased to 5-6 litres (or 10 kg). In 1986 a plastic sieve with 1 mm holes used and filled three times (5-8 kg) for each sample, the volume of fines was measured. C. 10 gram of each sample was analysed by Bondar-Clegg for (Sc, Cr, Fe, Co, Ni, As, Se, Rb, Mo, Ag, Cd, Sb, CS, BA, La, Eu, Tb, Yb, Hf, Ta, W, Ir, Au, Th and U) analyses. The reader should note that the analyses below detection limit is given as "0" (zero) and not analysed as "-1" for the samples collected in this campaign (year 1982-1986, i.e. batch numbers 10, 35 and 55). Year 1991 In 1991, 106 streams were sampled for heavy mineral concentrate, in the southern part of the Nuuk area, between 62°30?N and 64°N. Sample procedure was as follows: 5-10 litres of detrital material, < 5 cm, were collected, from 2-5 sub-localities in the stream bed. Wet sieving split the sample in less-than and bigger-than 0.5 mm, and the coarser fraction inspected for economic minerals. The fine fraction was heavy minerals concentrate was produced using a rotary panning device "goldhound" (see Erfurt et al., 1992 for reference). The heavy mineral concentrate was shipped to Denmark and dried and further spilt for analytical purposes. Activation Laboratories, Canada, analysed the samples for 35 elements including gold, with INAA and ICP-ES. Analyses batches are numbered 10 and 36. Unique samples number 103 for these two batches. In additional batch 41, has analysed Pb, Cu, Ni and Zn. Year 2004 The analyses batch no. 193 and 194 have been described in GEUS report 2004/42, and were sampled in 2003 in the Qaanaaq region in North-West Greenland. Six samples were collected in this campaign and sieving of 1.0 mm material on site and a pre-concentrate by panning of the fine fraction. In Copenhagen minerals with > 2.8 g/cm3 density was produced by heavy liquid separation. The rest The remaining 406 samples (analyses batch numbers: 10, 15, 21, 35, 36, 41, 55, 165, 166, 193, 194, 374, 375, 376, 1014, 1015, 1016, 1017, 1029, 1030, 1051, 1052, 1077 and 1078) have been analysed in addition to the laboratories mentioned above, at Risø National Laboratory in Denmark. As reports have not been available for writing up these analyses, the description is limited to the analyses. Chances are, however, that sampling procedures are similar to the descriptions above. The analyses below detection limits of the remaining 406 unique samples have not been consistent, but are presented as "0" or as negative values and elements that have not been measured as "0" or empty cells.

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 regional aeromagnetic datasets were acquired from the Alfred Wegener Institute for Polar and Marine Research (AWI), Bremerhaven, Germany, in four field campaigns along the coastal regions of Northeast Greenland from 1993-1996. The line spacing ranges both in inline and crossline direction from 10-40 km and the levels range up to 3700 m. Presented maps are based on data reprocessed by GEUS.