bluuebunny/crossref_metadata_2025 huggingface dataset:
Sedimentological studies of the fluviatile-shallow marine Upper Triassic to Lower Jurassic succession in Jameson Land, East Greenland
Authors: Dam G
Published: June 2021

A three-year research fellowship programme supported by British Petroleum Development, London, was initiated in the summer of 1987. The main subject of the study is the Upper Triassic to Lower Jurassic succession in Jameson Land, East Greenland. This stratigraphic interval includes the Kap Stewart and the Neill Klinter Formations which have many features in common with some of the largest coeval hydrocarbon reservoir formations known in N.W. Europe (e.g. Statfjord fieid). The core of the project is a lithofacies analysis but ichnology, palynology, source-rock analyses and porosity/permeability analyses will be included where relevant. If possible, corresponding intervals from the Norwegian continental shelf will be included in the project. The aim of the project is: (1) to provide detailed and regional facies models for the two formations. Special stress wiIl be laid on the physical stratigraphic relations in order to ascertain if regional unconformities are present and what order of magnitude they may represent. (2) to establish a reservoir geological model which might help in the understanding of comparable reservoirs in the Norwegian-Greenland region. Particulal' attention will be paid to the geometry ofindividual sand bodies.
Preliminary report of fission track studies in the Jameson Land basin, East Greenland
Authors: Hansen K
Published: June 2021

Fission track (FT) analysis is especially suited to reveal and date low temperature events. The closure temperature of apatite (100 ± 30°C) and its annealing characteristics in the interval of 70-125°C are especially relevant to the study of the maturation of hydrocarbons (Gleadow et al., 1983). FT analyses were made on Permian to Cretaceous, quartzose sandstones and arkoses from the Jameson Land basin. Both FT ages and track length distributions for apatites were obtained for samples taken along the western and eastern margin of the basin (fig. land Table 1) in order to sttidy the tectonic and thermal history of the area. The investigation takes advantage of earlier FT work in the neighbouring Caledonian mountain belt which is believed to be the source of the terrigenous material, including the apatites, which make up the sediments (Hansen, 1985). A report of further Investigations in this area is in preparation.
Upper Devonian and Upper Permian vertebrates collected in 1987 around Kejser Franz Joseph Fjord, central East Greenland
Authors: Bendix-Almgreen S.E , Clack J.A , Olsen H
Published: June 2021

In July and August 1987 a five-man British/Danish vertebrate palaeontological expedition earried out field work on Gauss Halvø and eastern Ymer Ø to collect fossil vertebrates from exposures of the Upper Devonian continental and Upper Permian marine deposits. In the eontext of sampling for vertebrates the Upper Devonian deposits were last visited in 1955 when one af the writers (SEB-A) assisted the late Dr Eigil Nielsen with field work while the Upper Permian marine deposits have not been examined sinee Bendix-Almgreen's fieId work in the Kap Stosch area in the summer of 1967.
Stratigraphy and depositional history of the Upper Palaeozoic and Triassic sediments in the Wandel Sea Basin, central and eastern North Greenland
Authors: Stemmerik L , Håkansson E
Published: June 2021

A lithostratigraphic scheme is erected for the Lower Carboniferous to Triassic sediments of the Wandel Sea Basin, from Lockwood Ø in the west to Holm Land in the east. The scheme is based on the subdivision into the Upper Carboniferous - Lower Permian Mallemuk Mountain Group and the Upper Permian - Triassic Trolle Land Group. In addition the Upper Carboniferous Sortebakker Formation and the Upper Permian Kap Kraka Formation are defined. Three formations and four members are included in the Mallemuk Mountain Group. Lithostratigraphic units include: Kap Jungersen Formation (new) composed of interbedded limestones, sandstones and shales with minor gypsum - early Moscovian; Foldedal Formation composed of interbedded limestones and sandstones -late Moseovian to late Gzhelian; Kim Fjelde Formation composed of well bedded Iimestones - late Gzhelian to Kungurian. The Trolle Land Group includes three formations: Midnatfjeld Formation composed of dark shales, sandstones and limestones - Late Permian; Parish Bjerg Formation composed of a basal conglomeratic sandstone overlain by shales and sandstones - ?Early Triassic (Scythian); Dunken Formation composed of dark shales and sandstones - Triassic (Scythian-Anisian). The Sortebakker Formation (new) is composed of interbedded sandstones, shales and minor coal of floodplain origin. The age is Early Carboniferous. The Kap Kraka Formation (new) includes poorly known hematitic sandstones, conglomerates and shales of Late Permian age.
Chitinozoans from Ordovician and Silurian shelf and slope sequences in North Greenland
Authors: Grahn Y , Nøhr-Hansen H
Published: June 2021

This first study on chitinozoans from Greenland has revealed representatives of twenty-two chitinozoan species recovered from Ordovician and Silurian beds in North Greenland. The Ordovician faunas are sirnilar to those described from North Arnerica, while the Silurian faunas are more sirnilar to those of Baltoscandia. Four distinct assemblages can be separated between Maysvillian - early Garnachian and Ludlow. The chitinozoan biostratigraphy is in agreement with that of the graptolites but differs from the conodont biostratigraphy.
Evaluation of the niobium-tantalum potential of the Motzfeldt Centre, South Greenland
Authors: Thomassen B
Published: June 2021

The Motzfeldt 87 Project, initiated in June 1987, was completed in May 1988 with the publication of the final report (Thomassen, 1988). The project consisted of a detailed investigation of selected parts of the niobiumtantalum-uranium-bearing pyrochlore mineralisation at Motzfeldt Sø, South Greenland (fig. 1). The purpose of the project was to gain a general impression of the metal distribution in the mineralised zones and to delineate areas with high metal contents. The project was carried out as a joint programme between GGU and Nunaoil AJS under the supervision of GGU, and was mainly funded by the Mineral Resources Administration for Greenland.
Geological investigations of Prinsesse Ingeborg Halvø, eastern North Greenland
Authors: Håkansson E , Madsen L , Pedersen S.A.S
Published: June 2021

Station Nord in Kronprins Christian Land has been the gateway to North Greenland for most geologists since the 1950s, yet little is actually known about the geology of Prinsesse Ingeborg Halvø, the low, barren stretch of land which surrounds the station. A major objective of the Ingeborg Expedition in July and August 1988 was to fill this gap by folIowing up work initiated during the GGU expedition in 1980 (Håkansson et al., 1981).
The northern boundary of the Proterozoic (Nagssugtoqidian) mobile belt of South-East Greenland
Authors: Dawes P.R , Soper N.J , Escher J.C , Hall R.P
Published: June 2021

The Proterozoic mobile belt of South-East Greenland has been regarded as a classic example of amphibolite facies reworking of an Archaean granulite facies gneiss terrain. Its northern boundary has been interpreted as a transcurrent shear zone in which reworking was associated with major basic dyke emplacement. A re-examination of the northern boundary shows it to be a diffuse region more than 50 km wide in which retrogression, unrelated to dykes or shear zones, gradually intensifies southwards. Superimposed on this are discrete belts of retrogression associated with dykes and shear zones. The sense of displacement on the latter is compatible with thrusting of the northern Archaean block southwards over the reworked terrain of the mobile belt.
The southern boundary zone of the Proterozoic mobile belt, South-East Greenland: geology of the area between Gyldenløve Fjord and Isertoq
Authors: Escher J.C , Friend C.R.L , Hall R.P
Published: June 2021

The Gyldenløve Fjord – Isertoq region consists mainly of grey amphibolite facies gneisses with rare units of supracrustal rocks. The region is cut by a dense swarm of E–W trending basic dykes which are presumed to be of Proterozoic age. The dykes clearly predate the Proterozoic deformation of the northern and central parts of the region, which represents the southern part of the Proterozoic mobile belt of South-East Greenland. The gneisses south of the mobile belt in the southern part of the region are presumed to be Archaean and are cut by undeformed dykes. The gneisses and dykes within the mobile belt, in contrast, have been strongly sheared and folded but contain occasional tectonic augen of nebulitic gneiss with variably preserved Archaean structures. The southern boundary of the mobile belt bordering the unmodified Archaean gneisses consists of an approximately 25 km wide zone of gradually declining deformation and is in many respects comparable to the northern boundary of the mobile belt, described elsewhere in this volume.
Lower Cambrian trace fossils from the Buen Formation of central North Greenland: preliminary observations
Authors: Bryant I.D , Pickerill R.K
Published: June 2021

The trace fossils Cruziana cf. C. stromnessi (Trewin, 1976), Curvolithus Fritsch, 1908, Hormosiroidea Schaffer, 1928, Monomorphichnus cf. M. bilinearis Crimes, 1970, Monomorphichnus lineatus Crimes et al., 1977, cf. Palaeobullia Gotzinger & Becker, 1932, Palaeophycus tubularis Hall, 1847, Phycodes pedum Seilacher, 1955, Psammichnites Torell, 1870, Rusophycus Hall, 1852, Skolithos Haldeman, 1840 and cf. Zoophycos Massalongo, 1855 are recorded and briefly described from the Lower Cambrian Buen Formation, central North Greenland. Interbedded sandstones, siltstones and shales of the Buen Formation were deposited in a tide and storm-dominated shallow marine shelf environment. Ichnofaunal diversity is low in monolithologic cross-bedded sandstones, which characterise the basal portion of the sequence, and considerably higher in heterolithologic sandstones, siltstones and shales, which occur higher in the sequence.
Towards a new decade in Greenland geology Review of the Survey's activities in 1989
Authors: Ghisler M
Published: June 2021

Nineteen-eighty-nine brings to an end a decade which has seen many changes in the demands and aspirations expressed by society concerning geological investigations in Greenland. The Geological Survey of Greenland (GGU) has responded to these new expectations by seeking to change the emphasis of its geological activities. Since its inception more than 40 years ago, GGU has surveyed the framework of Greenland geology through a series of mapping programmes and regional investigations aimed at establishing a solid scientific foundation upon which applied and economic geological and hydrological activities could be based. In later years, applied and economic activities have played an increasing role in GGU's planning, and 1989 has seen a continuation of this trend as GGU meets the challenge of a new decade.
Regional geology and 1:500 000 mapping in North-East Greenland
Authors: Henriksen N
Published: June 2021

A three-year field mapping programme was initiated in 1988 aiming at regional geological studies and geological mapping in North-East Greenland between latitudes 75° and 78°N. This region encompasses relatively little known parts of the Caledonian fold belt and the overlying post-Caledonian sequences, which lie north of the better known regions of central East Greenland (Henriksen, 1989). Major aims of the programme include compilation a 1:500 000 geological map, and an understanding of the general geology of the region.
Regional marine seismic reconnaissance
Authors: Larsen H.C , Pulvertaft T.C.R
Published: June 2021

The only offshore multi-channel reflection seismic survey that has been carried out by GGU until now is project NAD (North Atlantic D), a survey which covered most of the eastern Greenland shelf between 63° and 72°N (Larsen, 1985, in press). This survey was made possible by a large grant from the EEC. After Greenland's withdrawal from the EC in 1985 it became doubtful if support for further major projects offshore Greenland could be obtained from the EEC.
Deep seismic profiling in central West Greenland
Authors: Skjellerup P , Smithson S.B , Larsen H.C
Published: June 2021

During September 1989 a survey of the Godthåbsfjord area was carried out in order to study the deep seismic structure of high-grade Archaean crust (Bridgwater et al., 1976; McGregor et al., 1986). Refraction profiles were made along Godthåbsfjord and Ameralik. Receiver stations were placed along the fjords and inland to provide cross-profiles and 3-D coverage (fig. 1). Marine air-guns provided the seismic energy source.
Geochemistry in GGU
Authors: Kalsbeek F
Published: June 2021

Chemical analyses are essential for many of GGU's activities, especially in the search and evaluation of mineral resources and in the study of rock units. GGU has a well-equipped laboratory for the analysis of rock material, and has a close cooperation with laboratories belonging to the Department of Geology of the University of Copenhagen and the Risø National Laboratory, Denmark.
Volcanic marker horizons in the Maligât Formation on Disko and Nûgssuaq, and implications for the development of the southern part of the West Greenland basin in the early Tertiary
Authors: Larsen L.M , Pedersen A.K
Published: June 2021

Two volcanic units in the feldspar-phyric basalts of the Rinks Dal Member each have a distinct chemical composition and sometimes lithology, and can be recognised over large areas. A pahoehoe unit filled a c. 60 m deep water basin which existed over a long period in eastern Disko, confined between the Disko gneiss ridge in the west, volcanics in the north, and a fluvial plain in the south-east. After the deposition of the pahoehoe unit the topography was considerably more even, and a FeTi unit was able to spread throughout Disko and southern Nugssuaq. The FeTi unit consists of subaerial lavas and is thickest in the west where the eruption sites were located; it thins gradually toward the east, and in the eastern parts it is intercalated with sandstones and shales. The FeTi lavas have sometimes invaded the sediments to form sill-like bodies. Intercalated with the FeTi unit are shales of the Aussivik Member on Nugssuaq, shales and sandstones on northern east Disko, and sandstones throughout the rest of Disko. Thus lateral time-equivalent facies differences are demonstrated. The general palaeoslope from west to east shows that the continental margin to the west had not yet begun to sag.
Facies mapping and reservoir evaluation of the Upper Permian Wegener Halvø Formation along the western margin of the Jameson Land basin, East Greenland
Authors: Stemmerik L , Scholle P.A , Henk F.H , Di Liegro G , Mantovani M , Ulmer D.S
Published: June 2021

The depositional pattern of the Upper Permian Wegener Halvø Formation is mainly controlled by the karst topography of the surface of the underlying Karstryggen Formation. The area was divided by a NNW–SSE trending depositional and/or erosional high during Late Permian times. Peritidal carbonates and evaporites are dominant on the platform to the west while to the east oolite and biogene grainstone deposits dominate. Reservoir-quality properties are mainly confined to the grainstone deposits east of the high.
Post-Caledonian sediments in North-East Greenland between 76° and 78°30'N
Authors: Stemmerik L , Piasecki S
Published: June 2021

Post-Caledonian sediments in North-East Greenland between 76° and 78° 30´N are, with the exception of an outlier near Kulhøj, restricted to Store Koldewey. The sediments on Store Koldewey, believed to span the Middle Jurassic to Lower Cretaceous (Callovian to Aptian), are dominated by fine-grained sand and silt. They contain a rich macrofauna which, together with material collected for microfloral investigations, will form the basis for a detailed stratigraphy and dating of the sequence.
Reservoir evaluation of Upper Permian buildups in the Jameson Land basin, East Greenland
Authors: Stemmerik L
Published: June 2021

The Upper Permian Wegener Halvø Formation buildups form an important reservoir target in the Jameson Land basin. Due to absence of subsurface information from the basin, reservoir properties of the buildups are tentatively evaluated by timing the different diagenetic modifications seen in outcrop relative to hydrocarbon migration.The buildups became cemented during deposition and the ultimate porosity was dose to zero. Post-depositional porosity appears to be related to freshwater dissolution of aragonite cement during Permian exposure events. Reservoir potential is mainly confined to the buildup cores and the proximal flank deposits. Porosity prior to hydrocarbon migration is estimated to average 10% in the buildups and 5–6% in the proximal flank deposits. Pores became filled by hydrocarbons probably in the Late Cretaceous; the reservoirs became flushed by hot, hydrothermal fluids c. 20 Ma ago and pores are now filled by iron-rich calcite, baryte and fluorite. The flushing of the reservoir may be related to the Tertiary uplift of Wegener Halvø, and it is most likely a local event not affecting the basin as a whole.
A Silurian trilobite fauna dominated by Calymene from Kap Tyson, western North Greenland
Authors: Lane P.D , Siveter D.J
Published: June 2021

The Silurian trilobites described here are referred to 5 genera and 5 species-level taxa of which Calymene iladon is new. The composition of the fauna is unusual for North Greenland in that it is overwhelmingly dominated by specimens of Calymene. Other elements of the fauna are known from other areas of North Greenland, and at least closely related forms of one of them have cosmopolitan distributions.
Gordia nodosa isp nov and other trace fossils from the Cass Fjord Formation (Cambrian) of North Greenland
Authors: Pickerill R.K , Peel J.S
Published: June 2021

A new ichnospecies, Gordia nodosa isp. nov., is figured and described from member D of the Cass Fjord Formation of Daugaard-Jensen Land, western North Greenland. Strata of Member D are Dresbachian in age and thus the new trace fossil is from the latest Middle Cambrian or earliest Late Cambrian. Two additional stabs from underlying members B and C of the Formation contain, respectively, the ichnotaxa Diplichnites Dawson, 1873, cf. Monocraterion Torell, 1870 and Palaeophycus tubularis, Hall, 1847, and Cruziana problematica (Schindewolf, 1921). These ichnotaxa are figured and described briefly.
Gardar mantle xenoliths: Igdlutalik, South Greenland
Authors: Upton B.G.J
Published: June 2021

A dyke of presumed Gardar age on Igdlutalik island near Narsaq contains an abundance of ultramafic xenoliths. Both host rock and xenoliths have been metamorphosed and the original mineral assemblages largely replaced by tremolite, chlorite and magnetite. Textural and geochemical evidence suggests: (a) that the host rock was a part of the ultramafic lamprophyre suite known throughout the Tugtut6q-Ilimaussaq-nunataq lineament, and (b) that the xenoliths were mantle-derived peridotites (possibly garnetiferous), together with some glimmerites that may be analogues of MARID-suite xenoliths known from kimberlite occurrences.
Review of the Survey's activities in 1990
Authors: Ghisler M
Published: June 2021

Negotiations on a new strategy for exploration and utilisation of the mineral resources in Greenland were started during the year between the Greenland Home Rule Authorities and the Danish state. This strategy aims to encourage the mining and oil industry to intensify exploration activities in Greenland. In connection with this new approach, the Geological Survey of Greenland (Grønlands Geologiske UnderSøgelse, GGU) has continued and developed initiatives to facilitate ready access to relevant geological, geophysical and geochemical data held by the Survey.
Geochemical mapping: distribution of gold, arsenic, antimony and tantalum in South Greenland
Authors: Steenfelt A , Tukiainen T
Published: June 2021

New graphics software utilising raster techniques has been developed at the Geological Survey of Greenland (GGU) during 1989 and 1990 for presentation of geochemical and geophysical areal data. The software is very suitable for the display of the regional variation of chemical elements as contoured colour maps of interpolated data. In this paper we show the distribution patterns for a few selected elements of economic interest, which have been determined in stream sediment samples collected in South Greenland in 1979. The implications of the new information for the mineral potential of the region are briefly discussed.
Feldspar megacrysts and anorthosite xenolith-bearing dykes in the Narssarssuaq area, South Greenland
Authors: Winther T
Published: June 2021

Numerous dyke intrusions are found in the Narssarssuaq area of the Gardar province, a Mid-Proterozoic intracontinental rift system. Ten to fifteen percent of these dykes, which range in composition from trachybasalt to phonolite and rhyolite, contain significant proportions of feldspar megacrysts and occasionally anorthosite xenoliths. Two groups of dykes are distinguished; the older group is more alkaline, richer in incompatible elements and contains more anorthosite xenoliths than the younger. It is probable that the main reason for the differences is variation in magma production through time and from one area to another. Chemical zonation in the dykes reflects compositional gradients in the feeding magma reservoirs; the magma reservoirs acting as open systems in which crystal fractionation was an important controlling process. The anorthosite xenoliths are not strictly cognate with their hosts, but were derived from comparable alkaline magmas with a composition roughly corresponding to the most primitive of the dykes. The plagioclase megacrysts were presumably formed at an early stage of the development of the magma chambers. Rb-Sr dating of one of the dykes from the older group of dykes gives an age of 1206 ± 20 Ma and an initial 87Sr/86Sr ratio of 0.7028 ± 0.0001 supporting a low degree of contamination with upper crustal Sr.
Review of the Survey's activities in 1991
Authors: Ghisler M
Published: June 2021

The new Mining Law for Greenland, approved in 1991 by the Danish and Greenlandic governments, was designed to encourage interest in exploration and utilisation of mineral resources in Greenland by creating more favourable operating conditions for the oil and mining industry. The activities of the Geological Survey of Greenland (Grønlands Geologiske Undersøgelse, GGU) in 1991 have reflected this new strategy. In the hydrocarbon field a new information prospectus has been prepared for the forthcoming licensing round for selected areas offshore West Greenland, while initiatives to attract interests of mining companies have been intensified.
Petroleum geological activities in 1991: reassessment of earlier exploration, and improvement of information service to industry
Authors: Christiansen F.G , Pulvertaft T.C.R
Published: June 2021

The shift of emphasis in the petroleum-geological activities of the Geological Survey of Greenland (GGU) from East to West Greenland that was described in the Report of Activities 1990 was consolidated in 1991 in so far as onshore activity is concerned, as the main onshore field activity was in the Cretaceous-Tertiary outcrops in central West Greenland. Offshore West Greenland, reinterpretation of industry data from the 1970s was continued (see Chalmers, 1990). In May processing of the 5200 km seismic data acquired offshore West Greenland in 1990 was completed and interpretation of the data began, and in July two supplementary lines totalling 336 km were acquired offshore West Greenland using the KANUMAS project's vessel Thettis prior to its departure to North-East Greenland. Any geographical bias there may be towards West Greenland is however subsidiary and largely coincidental to the overall current emphasis in GGU's petroleum-geological activities, which is the reassessment of areas of earlier exploration with regard to coming licensing rounds in Greenland. In November 1991 the Mineral Resources Administration for Greenland (MRA) issued a press release in which the time-table for coming licensing rounds offshore West Greenland was outlined. The first of these rounds was announced formally in early April 1992, with the closing date for submission of applications 15 January 1993. The Jameson Land basin in East Greenland has been declared 'open acreage' , and interested companies are invited to contact MRA to discuss licensing terms. An exploration report on the Jameson Land basin specifically designed for management has been prepared by GGU and is now on sale.
Disko Bugt Project 1991, West Greenland
Authors: Kalsbeek F , Christiansen F.G
Published: June 2021

One of GGU's major field activities in 1991 took place in July and August in the Disko Bugt region of central West Greenland. This was the third year of field investigations under the 'Disko Bugt Project', planned for 1999–1992, with one summer's break in 1990. The project spreads over various activities and over two very different geological provinces: the Archaean-Proterozoic basement east and north-east of Disko Bugt, and the onshore part of the Cretaceous-Tertiary basin in the west, on Disko and the western part of Nugssuaq (Fig. 1). In 1989, the second year of the project, work was concentrated in the eastern basement part of the study area, and in 1991 this work was brought to conclusion. In 1992 field work (including a shallow core drilling campaign) will be concentrated in the sediments and volcanics on Nugssuaq and Svartenhuk Halvø to the north. The main aim of the Disko Bugt Project is to provide a background for the evaluation of the economic potential of the regional mineral resources, mainly in the Precambrian basement, and the hydrocarbon potential of the neighbouring basin offshore (see Kalsbeek, 1989. 1990).
The gold and base metal potential of the Lower Proterozoic Karrat Group, West Greenland
Authors: Thomassen B
Published: June 2021

The mineral potential of the Karrat Group in West Greenland became important after exhaustion in 1990 of the Black Angel lead-zinc mine situated within this supracrustal unit. It consists of shelf and turbidite type metasediments and subordinate metavolcanics deposited in an epicontinental marginal basin. Known mineralization comprises the Black Angel deposit and a number of other marble-hosted lead-zinc occurrences, as well as extensive sulphide facies iron formations and vein type base and precious metals mineralisation in quartzites and metagreywackes. Further areas with anomalously high contents of both base metals and gold-arsenic-tungsten are indicated by drainage geochemistry. The mineral potential of the Karrat Group is for massive base metal sulphide deposits hosted in marbles or clastic metasediments, and turbidite hosted gold-bearing veins and shear zones.
Volcanic marker horizons in the upper part of the Maligât Formation on eastern Disko and Nuussuaq, Tertiary of West Greenland: syn- to post-volcanic basin movements
Authors: Larsen L.M , Pedersen A.K
Published: June 2021

Lavas from the Rinks Dal, Nordfjord and Niaqussat Members of the Maligat Formation overlying gneisses in eastern Nuussuaq are described together with an overlying young sequence of basalts not known from other areas. The Niaqussat Member lavas are the first recorded from Nuussuaq. On Disko lavas of the Nordfjord and Niaqussat Members have been found on the highest mountain tops bordering the Sermersuaq ice cap, and these two members are now known to have been present over the whole of Disko and eastern Nuussuaq. East of the Disko Gneiss Ridge the base of the Niaqussat Member forms a fairly smooth, gently south-easterly sloping surface that can be extrapolated to Nuussuaq. Eruption sites for the Nordfjord and Niaqussat Members are centred in western Disko, but feeder dykes east of the Disko Gneiss Ridge are indicated, especially for the Niaqussat Member in both Disko and Nuussuaq. There is evidence from several levels within the volcanic pile of relative subsidence in the south-east and uplift in the north-west, and these movements must have taken place in an extended period both during and after the volcanic activity.
An application of multi-model photogrammetry in the study of a Tertiary shale unit, north-east Disko, West Greenland
Authors: Pedersen G.K
Published: June 2021

Multi-modal photogrammetry has been applied in a study of the lateral continuity of lithofacies in a dark grey shale unit on the North-East coast of Disko. The shale is c. 60 m thick and can be traced laterally for 12 kilometres. It is demonstrated that it distinct sand-streaked shale facies as well as contrasting thin pale sand units can be mapped confidently and that very accurate sections can be measured when the photogrammetric conditions are optimal.
The application of multi-model photogrammetry in geology - status and development trends
Authors: Dueholm K.S , Pedersen A.K
Published: June 2021

The use of multi-models in geological photogrammetry enables free movement between stereoscopic images of different scales and angles of view. The method can be used for detailed analysis and three-dimensional mapping in a diversity of geoscience studies. Multi-model blocks can be stored and later reset easily and rapidly, which allows the gradual build-up of an archive of orientated stereo photographs that can be shared by many scientists. Further development of the multi-model method involves digital photogrammetry, digital image processing, computer modeIling, and geographical information systems.
An overview of Greenland's mineral exploration potential
Authors: Schønwandt H.K , Dawes P.R
Published: June 2021

Part of the 1992 promotion campaign to North America and Europe, to provide geoscientific data to exploration and mining audiences was an oral presentation of Greenland's exploration potential. The background and aims of the campaign are outlined elsewhere in this report by Dawes et al. The oral presentation focused on the main geological provinces of Greenland and their mineral occurrences (excIuding fossil fuels), but geographical and logistic subjects were also broached. This paper gives a summary of the geological part of the presentation and concentrates on metalliferous potential.
GGU Open File Series: a review of reports related to Greenland mineral exploration
Authors: Schønwandt H.K
Published: June 2021

In 1989 the Geological Survey of Greenland (GGU) increased its publication range by the introduction of an Open File Series, the aim of which was to speed up the presentation of new information to industry (Ghisler, 1990). This unedited series presents primarily raw data (field and analytical results) allowing exploration companies to use the information in assessment and planning. Although the series was formalised in 1989, a handful of reports of specific relevance to mineral exploration, and released by GGU up to three years previously, were numbered as the first six titles of the series. At the end of 1992, 40 reports made up the series.
Sedimentological and stratigraphical analysis of the Upper Triassic - Lower Jurassic succession in Jameson Land, East Greenland - a summary
Authors: Dam G
Published: June 2021

As part of ongoing studies of Mesozoic basin development and hydrocarbon potential in East Greenland, a three-year research fellowship programme was initiated in the summer of 1987. The subject of the study was the Upper Triassic to Lower Jurassic succession in Jameson Land, East Greenland that includes the Kap Stewan and Neill Klinter Formations (Dam, 1988, 1989). This interval has many features in common with same of the largest coeval hydrocarbon reservoirs known in the northern North Sea; the outcrops in East Greenland provide an outstanding opportunity to study details of the architecture and sedimentary history of analogues of these reservoirs. The chief aim of the project was to establish detailed and regional facies models. and special emphasis was laid on the sequence stratigraphic relationships of the sediments in order to provide predictive models of reservoir characteristics. In addition the ichnology and source-rock potential of the formations have been studied. These studies have led to the establishment of a new formal lithostratigraphic and sequence stratigraphic scheme, and the unravelling of the palaeogeographic evolution of tile basin.
Ocean Drilling Program (ODP) off South-East Greenland: formation of a volcanic rifted margin
Authors: Larsen H.C
Published: June 2021

The exposures of the Tertiary igneous rocks along the East Greenland coast (Fig. I) have attracted the attention or earth scientists for more than half a century (Wager, 1934; Wager & Deer 1938). However, most of the work has concentrated on the petrological and mineralogical aspects of the magmatic rocks (e.g. Skaergaard intrusion). With a few exceptions, such as Brooks (1973). Nielsen (1978). H. C. Larsen (1978), Branks (1979), Myers (1980) and Nielsen & Branks (1981). Relatively little attention has been given to the tectonic and plate tectonic setting. mainly because the plate tectonic paradigm did not become accepted until 30 years after Wager and Deer's revolutionary work. Furthermore, the tectonic context of the coastal exposures first becomes really striking when seen together with the geology and structure of the adjacent continental shelf and slope (H.C. Larsen, 1990).
Sm-Nd isotope age data from the Archaean Skjoldungen area, South-East Greenland
Authors: Kalsbeek F , Taylor P.N
Published: June 2021

Sm-Nd model ages for ten basement gneisses and intrusive rocks from the Skjoldungen area in South-East Greenland range from 2.73 to 2.91 Ga. Two rocks yielded older ages: a high-grade metasedimentary rock (2.96 Ga) and a pegmatite (3.13 Ga). Sm-Nd data are now available for a more than 700 km long stretch of the south-east coast of Greenland between 63° and 68°N. No evidence has been found for the presence of early Archaean (> 3.5 Ga) rocks, and early Proterozoic gneisses have only been found in the Ammassalik area (65° 30'N).
Project SUPRASYD 1993 - granitic rocks and shear zones with possible gold potential, Julianehåb batholith, South Greenland
Authors: Garde A.A , Schønwandt H.K
Published: June 2021

In 1992 the Geological Survey of Greenland (GGU) initiated the project SUPRASYD in order to carry out an economic assessment of the Ketilidian orogen in South Greenland, especially the supracrustal rocks in the southern and eastern parts of the orogen (see Dawes & Schønwandt, 1992). Geological investigations in the area east of Nanortalik and along the east coast of South Greenland as far as 62°N had previously indicated that acid metavolcanic rocks were an important constituent of the supracrustal rocks, and it was therefore expected that the region might have a significant potential for sulphide deposits.
Petroleum-geological activities in 1993: oil source rocks the dominant theme of the season's field programme
Authors: Christiansen F.G , Pulvertaft T.C.R
Published: June 2021

After three years with a high level of activity in Greenland, both onshore and offshore, the scope of petroleum related field activities in 1993 was relatively restricted. No seismic acquisition was carried out either by GGU or by the KANUMAS group of companies, but onshore there was activity in both West and East Greenland, mainly concerned in one way or other with oil source rocks and factors governing their distribution and potential.
Reaction of Precambrian high-grade gneisses to mid-crustal ductile deformation in western Dove Bugt, North-East Greenland
Authors: Chadwick B , Friend C.R.L
Published: June 2021

Mid-crustal deformation of an Early Proterozoic high-grade gneiss complex in western Dove Bugt gave rise to at least two sets of nappes. Structures in mylonites in low-angle ductile shear zones associated with the younger nappes indicate north-easterly-directed displacements. The nappes and mylonites are folded by upright to inclined folds that verge north-west and which appear to be associated with decollements that dip south-east. Hornblende, sillimanite and anatectic partial melts that developed with the nappes, mylonites and younger folds show that deformation took place under amphibolite facies conditions. Several lines of evidence suggest that the younger nappes, the mylonites and the upright to inclined folds formed during the Caledonian orogeny. Some pre-Caledonian deformation may be represented by the oldest isoclinal folds. Numerous, small-scale, ductile extensional shear zones and more brittIe fractures that were superimposed across the Caledonian structures are believed to have formed during orogen-parallel collapse which may be related IO Devonian basin development farther south in central East Greenland. Younger fauIts and major joints are correlated with Carboniferous, Mesozoic and Tertiary basin development in North-East Greenland.
Eclogites and related high-pressure rocks from North-East Greenland
Authors: Gilotti J.A
Published: June 2021

Eclogite, gamet clinopyroxenite, gamet websterite and websterite bodies were discovered within the Skærfjorden gneiss complex during recent mapping in North-East Greenland. These eclogitic pods extend from Danmarkshavn (c. 76° 40'N) to the northern limit of the area mapped (78°N), and attest to widespread high-pressure metamorphism. Eclogites with the assemblage omphacite + garnet ± quartz ± futile are common. The protoliths of some of the eclogites were xenoliths within the precursor batholiths to the gneisses. Field relations, regional correlations and preliminary geochronology indicate that the eclogite facies metamorphism is Caledonian. The eclogites formed at minimum pressures between 10-15 kilobars and temperatures between 600–900°C, and hence are the medium-temperature type typically formed in over-thickened crust during continent collision.
Stratigraphy and correlation of the Tertiary plateau basalts in North-East Greenland
Authors: Watt W.S
Published: June 2021

The Hold with Hope – Wollaston Forland area with the adjacent islands is partly covered by Tertiary plateau basalts. The area is divided into structural blocks by NNE–SSW faults with apparent eastward down-step and the basalt succession of the mainland is repeated on the islands to the east. Individual profiles are correlated using distinctive features of the development of their chemistry with height. A succession of 600–700 m of uniform tholeiitic lavas compose a lower sequence which extends over the whole area. This is overlain locally by an intervolcanic conglomerate followed by 500 m of variable tholeiites and alkali-basalt lavas. This upper sequence is restricted to the southern part of the volcanic area. The northerly occurrence of a dyke chemically associated with the upper sequence suggests that this sequence originally extended much further north than its present outcrop.
Seismic stratigraphy and tectonic evolution of the Lower Cretaceous in the Danish Central Trough
Authors: Vejbæk Ole Valdemar
Published: June 2021

The Lower Cretaceous sequence of the Danish Central Trough has been studied by the use of seismic stratigraphic analysis. The sequence has been subdivided into 6 seismic stratigraphic units named LCA, LCB, LCC, LCD, LCE and LCF. The studied area includes the Feda Graben, the Gertrud Graben (new name), the Tail End Graben, the Arne-Elin Graben (new name) and the Salt Dome Province, whereas the Grensen Nose and the Outer Rough Basin are not included. These basins are separated by the Inge High, the Mads High, the Gert Ridge (new name), the Manda! High, the Heno Plateau (new name) and the Pollerne Ridge (new name). The fault controlled subsidence of the Lower Cretaceous basins is claimed to have been governed by left lateral transtensional wrenching. This wrenching gradually ceased and gave way to regional subsidence with intermittent events of inversion resulting from right lateral transpressive wrenching in the Late Cretaceous and Early Tertiary. The first weak inversion is shown to have occurred in the Late Hauterivian. Sedimentation was influenced by a general gradual relative rise in sea-level starting with a low in the Volgian - Early Ryazanian times coeval with the deposition of the Farsund Formation and culminating in the Late Cretaceous. At the beginning of the Early Cretaceous gravity flow became an important depositional mechanism and resulted in preferred deposition in topographical lows, which were generated by simple tensional block-faulting or by wrench-induced, rapid local subsidence. As tectonic activity decreased and the elastic source areas became more remote and worn down, depocentres became less pronounced, especially with the last unit of the Lower Cretaceous.
Jurassic - Lower Cretaceous of the Danish Central Trough; - depositional environments, tectonism, and reservoirs
Authors: Michelsen Olaf , Frandsen Niels , Holm Lise , Jensen Thorkild Feldthusen , Møller Jens Jørgen , Vejbæj Ole Valdemar
Published: June 2021

A revised model for the Jurassic - Early Cretaceous basin development in the Danish Central Trough is described on the basis of new studies of the bio- and lithostratigraphy and sedimentological and seismic data. The trough has been subdivided into a number of areas, each characterized by specific structural evolution. Middle Jurassic fluvio-deltaic and coastal sands follow the mid Cimmerian unconformity and probably cover large parts of the trough. Right-lateral movements, initiated during the Late Jurassic along WNWESE trending faults, caused fault controlled basin subsidence. The Jurassic and early Early Cretaceous sedimentation were dominated and characterized by clay. More than 4000 m of clay were deposited. Organic carbon rich clays were deposited from the Kimmeridgian until the Late Ryazanian, when deposition of organic carbon poor sediments under oxygenated conditions commenced. During the Late Jurassic transgression coastal sands were deposited along tectonically quiet basin margins. Sands deposited from density currents accumulated along tectonically active margins at the Jurassic-Cretaceous transition. More centrally in the basins, more distal turbidite deposits of Late Jurassic age may be present. Early Cretaceous basin expansion caused by elevation of the sea-level led to decreasing siliciclastic deposition rates and hence to more calcareous sediment types. Contemporaneously basin subsidence decreased. At mid Hauterivian time the importance of differential subsidence governed by left-lateral transtensional wrenching along NNW-SSE trending faults decreased. This change was accompanied by a mild inversion controlled by NNW-SSE directed right-lateral transpression, heralding regional subsidence. Following this inversion chalk was deposited in almost the entire trough area. Later, during the Barremian and Aptian anoxia in the basin caused deposition of marls rich in organic carbon, followed by marls deposited under oxygenated conditions during the Albian transgression. The distribution and character of possible reservoir bodies are discussed.
Geochemical investigation of Potassium-Magnesium Chloride mineralization of Zechstein 2 salt, Mors Dome, Denmark
Authors: Fabricius Johannes
Published: June 2021

Solid-rich inclusions at 20°C of the Na-K-Mg-Cl-H2O system, found in euhedral quartz from the top of Zechstein 2 salt in the Mors dome, Denmark, were objects of microthermometrical investigation. The quartz crystals, all of the long prismatic, slender type, average length of 750 μm, are genetically closely connected to the intercalated clay in the deck halite Na2r. The inclusions are faceted negative crystals, crystallographically orientated with the host quartz. Carnallite (KMgCl3 ·6H2O) is the main daughter mineral, followed by tetrahydrate (MgCl2-4H2O) and minor sylvite (KCl). Halite (NaCl) is found as grains in suspension in the trapped solutions. The trapped solutions represent melts of carnallite or tetrahydrate saturated with NaCl. The concentrations range from 167 mol MgCl2 + 83 mol K2Cl2 +3 mol Na2Cl2 per 1000 mol H2O to 250 mol MgCl2 + 5 mol K2Cl2 + 0 mol Na2Cl2 per 1000 mol H2O, corresponding to salinities from 52 to 62 weight%. Melting temperatures measured, 170-185°C, and estimated pressures, 80-110 MPa, are minimum trapping values. In a few cases highly irregular, "dry" grains of carnallite, containing dissolved high-pressure gas, were observed to have been trapped. In this study it is shown that the melting temperature of carnallite in a closed space, where evaporation is prevented, depends on the prevailing pressure. It is also shown that high-pressure gas is dissolved in trapped grains of carnallite or halite, but not in the solutions. Finally, the results lead to the proposal of a model, related to time and space, of the metamorphism of an original carnallitic potash bed and subsequent K-Mg-Cl mineralization of the deck halite. The original paragenesis kieserite-halite-carnallite, sedimented in the deeper parts of the basin, was altered to the present kieseritic hard salt by means of progressive geothermal metamorphism from Upper Triassic to Lower Cretaceous. The hanging wall of the potash bed, the deck halite, was mineralized by the metamorphic solutions, squeezed out from the potash bed, possibly during the diapiric penetration phase in Upper Jurassic - Lower Cretaceous.
Lower Cretaceous calcareous nannofossil biostratigraphy in the Danish Central Trough
Authors: Thomsen Erik
Published: June 2021

Calcareous nannofossils are described from Lower Cretaceous strata of four borings in the Central Trough of the Danish North Sea sector, and from three Aptian units on Helgoland and at Sarstedt, northern Germany. The assemblages range in age from Upper Hauterivian to Albian-?Cenomanian. Abundances of calcareous nannofossils varied considerably throughout the investigated sequences. They were rock-forming in several Lower Barremian - Aptian sediments, but rare or lacking in many of the Hauterivian and Albian strata. The Middle Barremian - Lower Aptian assemblages were often dominated by nannoconids. Preservation was generally bad in chalk and good in marl deposits. Some finely laminated black sediments yielded extremely well-preserved assemblages. One hundred and sixteen species were recognized. Eighteen species were selected as biostratigraphically particularly useful and their chronostratigraphic ranges are shown and discussed. The ages of the investigated sequences were determined on the basis of the selected nannofossil events. Some distinct sedimentary units in the North Sea could be correlated with time-equivalent formations in eastern England and northern Germany.
Palynological zonation and stratigraphy of the Jurassic section in the Gassum No. 1-borehole, Denmark
Authors: Dybkjær Karen
Published: June 2021

The Jurassic section of the Danish onshore borehole Gassum No. 1 has been investigated palynologically. 126 palynomorph-taxa have been recognized, consisting mainly of microspores and gymnosperm pollen. The palynomorphs are treated morphosystematically. 71 samples were prepared and the relative abundances determined in 32 representative samples. 5 spore- pollen zones, A to E, have been defined based on the stratigraphical ranges and abundances of specific taxa. Correlating with data from Northwest Europe allows the zones to be dated as follows: Zone A: Late Rhaetian, Zone B: Hettangian, Zone C: Early Sinemurian to ?Pliensbachian/foarcian, Zone D: Kimmeridgian/ Early Volgian, Zone E: Middle Volgian. The relative abundances of the main morphological groups of palynomorphs have been calculated and their stratigraphical variations correlated with previously proposed Early Jurassic sea-level changes.