bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping in the Isukasia area
Authors: Allaart J.H , Hall R.P , Jensen S.B , Stecher O
Published: June 2021

During the summer of 1981 mapping of the two geological map sheets Ivisartoq 64 V.2 N and Isukasia 65 V.2 S was begun, and mapping continued on the sheet Fiskefjord 64 V.1 N. The map areas are situated between 64°30/ and 65°30/ N (fig. 15). A tent base camp was established at the fjord Kangiussaq in the eastern part of the Godthåb area. Thirteen geological field teams and the glaciological station at Qamanarssup serrnia, 50 km to the south-east, were supplied from this base camp. A Jet Ranger helicopter from Heliswiss chartered through Greenlandair Charter and the GGU cutter J. F. Johnstrup provided transport to the teams. Field work will continue in the area in 1982.
Field work in the Ujaragssuit nunât area, Ivisârtoq region, inner Godthåbsfjord, southern West Greenland
Authors: Chadwick B , Crewe M.A
Published: June 2021

FolIowing the successful completion of the Buksefjorden project, 63 V.1 N (1972-1979), the Geological Survey of Greenland and the Department of Geology, University of Exeter, have begun another joint project in the Ivisartoq region, 64 Y.2 N, in inner Godthåbsfjord. The field programmes (1981-1984) and laboratory studies at Exeter are being organised on lines similar to those of the Buksefjorden project, with supervision of four research assistants by B. Chadwick and K. Coe. M. A. Crewe and S. Robertson began work as research assistants in 1981. The generous support by the Survey, the University of Exeter, and the Natural Environment Research Council, UK, is gratefully acknowledged.
Geochemistry of the Malene metavolcanic amphibolites from Ivisârtoq: significance of the Archaean stratigraphy of southern West Greenland
Authors: Hall R.P
Published: June 2021

One of the most fundamental unresolved problems of tectonic modelling of the Archaean craton of West Greenland is the interpretation of the magmatic environment in which the ubiquitous Malene-type supracrustal rocks were formed and the relationship of these rocks to the pre-existing Amitsoq (c. 3750 m.y.) sialic crust in the Godthåbsfjord region at the centre of the craton. The Amitsoq gneisses are a complex of polyphase, pegmatite banded, tonalitic to granitic rocks and the Malene supracrustals are dominated by metavolcanic amphibolites associated with metasedimentary layers and ultrabasic bodies (Bridgwater et al., 1976). The present large scale intercalation of major Malene supracrustal and Amitsoq gneiss units is dearly the result of an early phase of thrusting (Bridgwater et al. 1974; Hall & Friend, 1979). However, whether the juxtaposition of the two suites originated from a cover-basement relationship or was purely tectonic in origin has been open to speculation.
Glaciological investigations at Qamanârssûp sermia, West Greenland
Authors: Olesen O.B , Braithwaite R.J
Published: June 2021

As part of the GGU programme for the regional mapping of the hydropower potential of West Greenland, glaciological and climatological investigations were continued on the Qamanårssup sermia (inventory number lCH21002) in 1981. The station was first established in late summer 1979 (Olesen, 1981) so that records for two whole summers are now available.
Glaciological investigations in connection with hydropower, South Greenland
Authors: Clement P
Published: June 2021

The glaciological investigations in South Greenland, started in the Johan Dahl Land area in 1977, were continued during the field season of 1981. Most of the work was concentrated on the Nordbogletscher, an outlet from the Inland Ice. Nordbogletscher terminates in the lake Nordbosø (660 m above sea level) which has been proposed as a reservoir for a hydroelectric project in the Nordbosø basin (GTO, 1980). The Nordbogletscher with an area of 208 km2 covers 68 per cent of the basin area (308 km2 ) and is the most important water source. Several small local glaciers with a total area of 5 km2 are also situated inside the basin. The total glacier cover of the Nordbosø basin thus amounts to 69 per cent. An understanding of the glacier dynamics and measurements of the mass balance are essential for the whole hydropower project. In addition to the work in Johan Dahl Land, mass balance measurements were carried out at Narssaq Bræ, a local glacier 10 km north-west of Narssaq town. Proposals for using the meltwater from the glacier for a local hydropower project have been made (GTO, 1980).
A simple model of runoff from ungauged basins in West Greenland
Authors: Braithwaite R.J
Published: June 2021

A simple model of runoff in West Greenland is proposed for the case that glaciers are in a state of balance. The independent variables in the model are estimated annual precipitation and evaporation while model parameters are evaluated by analyses of precipitation series from Greenland, and mass balance series from other parts of the world. The model ean be applied to ungauged basins for preliminary calculations of mean mnoff, reservoir capacities and relative error in mean runoff. Application of the model to sixteen proposed hydropower projects in West Greenland shows an order-of-magnitude agreement with earlier estimates. However, a more detailed analysis of runoff from Johan Dahl Land confirms that the mnoff there is less than originally estimated. The proposed reservoir appears to be adequate for 30-year storage but the design yield of the project must be reduced for safety. The shortcomings of the model should be obvious. They ean be best overcorne by an improved knowledge of hydrological conditions in the country resulting from systematic field observations.
Routine K/Ar age determination on post-Silurian dolerite dykes, North Greenland fold belt
Authors: Dawes P.R , Rex D.C , Soper N.J
Published: June 2021

This note documents results of routine K/Ar isotopic age determination of dolerite dykes from the North Greenland fold belt. All the material was collected in 1969 by two of us (P.R.D. and N.J.S.) during the Joint Services Expedition to Peary Land; the isotopic analyses have been undertaken by D.C.R. in the geologicallaboratories of the University of Leeds. In view of the renewed interest in the tectonic and magmatic history of the Peary Land region stemming from the systematic field studies carried out by GGU in 1978-1980 (see GGU Rapport 88, 99 and 106), the results of this early dating programme are listed here as a contribution to this discussion. Recently, some reference has been made in the literature to these hitherto unpublished results (Dawes & Soper, 1979; Higgins et al., 1981; Håkansson & Pedersen, 1982).
Palaeoecological investigations of a Holocene peat deposit from Vølvedal, Peary Land, North Greenland
Authors: Bennike O
Published: June 2021

In connection with GGU's expedition to the Peary Land region, North Greenland, in 1979 and 1980, I had the opportunity to carry out some field work on the Quaternary geology of the Vølvedal area, and to collect a peat section (83°02'N, 34°21'W; fig. 4). Remains of Alona guttata and Calcarius lapponicus, which do not live in Peary Land today were found.
Geophysical and geological field work on fault structures at the Igaliko peninsula, South Greenland
Authors: Nyegaard P , Thorning L
Published: June 2021

Uranium exploration carried out in South Greenland by the Syduran project in the last few years (Armour-Brown et al., 1981) has indicated that certain major E-W fauIt structures are features worthy of attention in this connection. During August 1982 geological and geophysical field work was carried out 10 km south-south-east of Igaliko (fig. 25) around a fauIt zone which had earlier given indications of the presence of uranium mineral occurrences. The object of the geological work was to map the surface within the geophysical grid and to make a gamma-radiation survey of the area. Pitchblende veins, found in connection with geochemical prospecting, were traced by trenching and were sampled. The object of the geophysical work was firstly to evaluate the usefulness of various electromagnetic methods for locating and mapping the structures in the Julianehåb granite which contain uranium minerals and secondly to evaluate the extent of the known uranium mineral occurrences. Logistic support was supplied by the Syduran project base camp at Dyrnes.
Stratigraphy of the basalts of Savoia Halvø, central East Greenland
Authors: Watt W.S , Watt M
Published: June 2021

In the early 1970s the greater part of the basalts an the southern side af Scoresby Sund were mapped by the authors and a five-fold lithostratigraphic division was established for the area as a whole. In 1971 C. H. Emeleus mapped the basalts on the eastern part af Savoia Halvø (Emeleus, 1971) and K. Birkenmajer examined fhe overlying Tertiary sediments (Birkenmajer. 1972). The main objective af the work in the summer of 1982 was to correlate tbe lava succession as mapped by Emeleus in 1971 with the strategraphy established to the west and south-west. It was considered particularly important as the basalts here overlie black mudstoncs af Cretaceous age and also underlie the Eocene deposits of the Kap Dalton Formation. The authors have drawn extensively on Emeleus' mapping and have modified it according to tile geological divisions used here.
Marine geophysical investigations offshore East Greenland
Authors: Larsen H.C
Published: June 2021

During August and September 1982 a marine geophysical survey was conducted on the East Greenland Shelf. The survey was part of the ongoing regional project NAD (Larsen & Andersen, 1982; Andersen et al., 1981; Risum, 1980; Larsen & Thorning, 1980). In all 2794 km of 30-fold multi-channel seismic data and marine gravity and magnetic data were acquired (fig. 33). The object of the NAD programme is to acquire regional coverage of aeromagnetic, multichannel seismic refiection, seismic refraction (sonobuoy), marine gravity and magnetic data of the East Greenland Shelf between latitudes 60° N and 78°N. Aeromagnetic data comprising 63000 line kilometres were acquired in 1979 (Larsen & Thorning, 1980) and 5000 km of marine geophysical data were acquired in 1980 and 1981 (Larsen & Andersen, 1982; Andersen et al., 1981). This year the final data for the project were collected. Thus, a total of 7800 km of multi-channel refiection seismic data and 50 sonobuoy refraction seismic profiles of 20 to 70 km length have been acquired (fig. 33). In addition, marine gravity and magnetics were run at most lines.
Glaciological and climatological investigations at Qamanârssûp sermia, West Greenland
Authors: Braithwaite R.J
Published: June 2021

As part of the GGU programme of investigations in connection with hydropower in West Greenland, glaciological and dimatological measurements were continued at Qamanârssâp sermia (inventory number 1CH21002) in 1982. The station was first established in late summer 1979 so that records for three complete summers 1980-1982 are now available. Brief reports on the work have been given by Olesen (1981) and Olesen & Braithwaite (1982) while a more detailed field report and data summary for 1979-1981 is given by Braithwaite & Olesen (1982). A similar report for 1982 is now in preparation. The sketch map in figure 44 shows the lower glacier together with locations of stakes and survey points. It should be noted that the three highest stakes, numbered 013, 015 and 016, are located off the map to the north-east of Stake 012.
Tertiary volcanic rocks from Bontekoe Ø, East Greenland
Authors: Noe-Nygaard A , Pedersen A.K
Published: June 2021

In East Greenland Tertiary igneous rocks are found from Kap Gustav Holm (66°30'N) in the south to Shannon (75°30'N) in the north. Within this region three areas are covered by plateau basalts; (a) south of Scoresby Sund (700N), (b) far inland on the nunataks at 74°N and (c) along the coast between 73° and 75°30'N. Bontekoe ø belongs to the third region (fig. 1). The geology of this part of East Greenland is largely known from the activities of Lauge Koch's expeditions during which, curiously enough, the areas dominated by Tertiary volcanism were almost neglected. To remedy this the Geological Survey of Greenland supported some reconnaissance work that was carried out in connection with other geological activity in the region over the last few years. Results of this work were given by NoeNygaard & Pedersen (1974), Upton & Emeleus (1977), Hald (1978), Brooks et al. (1979) and Upton et al. (1980, 1982, in press).
Precambrian gneisses and intrusive anorthosite of Smithson Bjerge, Thule district, North-West Greenland
Authors: Nutman A.P
Published: June 2021

Smithson Bjerge is part of the Precambrian crystalline complex of North-West Greenland. The area comprises the Qaqujârssuaq anorthosite, the Heilprin Gletscher complex, paragneisses, multiphase orthogneisses and diverse minor granitic and basic intrusions. The Heilprin Gletscher complex comprises intimately associated granite, ferrogabbro and ferrodiorite. The Heilprin Gletscher complex and the Qaqujârssuaq anorthosite were intruded into the paragneisses and the multiphase orthogneisses, and may form an anorthosite-granite-ferrodiorite association. All lithological groups apart from the minor intrusions have been affected by large-scale overtumed folding and regional medium-pressure granulite facies metamorphism.
Review of the Survey's activities in 1983
Authors: Henriksen N
Published: June 2021

The Geological Survey of Greenland (GGU) continued in 1983 its scientific and practical investigations of the geology of Greenland and assisted in the promotion and controlof exploration and exploitation of raw materials in Greenland. GGU's work encompasses systematic geological mapping, geochemical and geophysical studies, petroleum geology, ore geology and glaciology. Much of this work is of scientific nature, but since it has often practical applications, a clear distinction between 'scientific' and 'applied' studies cannot be made.
Programme NordGrøn (PNG) 1983-1985: regional mapping and geological studies in western and central North Greenland
Authors: Dawes P.R
Published: June 2021

Programme NordGrøn (PNG) is planned as an onshore, regional mapping, and stratigraphic and structural study of the ice-free areas of northern Greenland between Humboldt Gletscher in the south-west (800 N) and western Peary Land to the east (c. 45°W) - a region of about 45 000 km2 (fig. 8). It is a sequel to the three-year programme carried out farther to the east in North Greenland in 1978-1980 (Peary Land to Kronprins Christian Land, see Henriksen, 1979, 1980, 1981 and GGU Reports 88 (1979), 99 (1980), 106 (1981). PNG is scheduled as a two-summer geological field activity in 1984 and 1985; in the summer of 1983, a three-man group visited the region to undertake logistic preparation and reconnaissance studies.
Comparative geochemistry of Archaean orthogneisses from the north-western quadrant of the Isukasia map sheet region, southern West Greenland
Authors: Hall R.P
Published: June 2021

The Archaean gneiss complex of the north-western part of the 1:100000 scale Isukasia map sheet region comprises predominantly of high-grade basic, intermediate and add metaigneous gneisses. Relict intrusive relationships clearly indicate the relative ages of most of the composite magmatic episodes. However, some relationships are not obvious and a geochemical reconnaissance has been made in an attempt to elucidate whether or nor any of the various units are genetically related. Since it is the preserved igneous geochemical affinities which are under investigation, the prefix 'meta' which should be applied to all of the lithologies is omitted.
Glacier meltwater chemistry at two sub-polar glaciers in West Greenland
Authors: Andreasen J.-O
Published: June 2021

As part of a glacier hydrological study electrical conductivity of meltwaters from two subpolar glaciers was investigated. The dissolved load of a melt stream reflects the mixing, in varying proportions through time, of waters with different chemical characteristics from different environments (Collins, 1977). Conductivity, a surrogate measure of the concentration af total dissolved solids, was used as an indicator af the nature af subglacial and englacial hydrochemical environments and of different meltwater routings through the glaciers. The investigation was carried out at Qamanârssup sermia, an outlet glacier from the Inland Ice, in 1981 and at Kitdlerssuaq, on an outlet glacier from a local ice cap, in 1982 and 1983 (fig. 45). All conductivity values are reported at the measuring temperature, i.e. 0-2°C for glacier meltwater.
Fission track dating of lower Tertiary rhyolitic glass rocks from Disko
Authors: Hansen K , Pedersen A.K
Published: June 2021

The Tertiary igneous activity in West Greenland has not been dated in detail. Sediments contemporaneous with, or slightly older than, the early volcanic rocks are assigned amiddle Paleocene age from palaeontological evidence (Henderson et al., 1981), and palaeomagnetic work by Athavale & Sharma (1975) indicates that the Vaigat Formation picrites and the lower 500 m or so of the overlying Maligât Formation (Hald & Pedersen, 1975) were erupted in the time span represented by geomagnetic anomaly 25 together with the long reversal period between anomalies 25 and 24. The age estimated for this period is 56 to 52 Ma (Butler & Coney, 1981). The late Stage lamprophyre magmatism on Ubekendt Ejland appears to be much younger, about 30 to 40 Ma (Parrott & Reynolds, 1975). No reliable radiometric age determinations have been published from the Disko-Nûgssuaq area.
Shallow-seismic, geoelectric and magnetic investigations of the Qaqarssuk carbonatite complex, West Greenland
Authors: Kjærgaard M , Olsen K.B
Published: June 2021

During the period 3rd July to 3rd September 1984 geophysical measurements were made in the Qaqarssuk area. The investigations focussed on: (1) Shallow-seismic and geoelectric investigations of the overburden, especiaIly its thickness. (2) Magnetic measurements in order to refine the modelling based on existing data from Kryolitselskabet Øresund AIS (Kurki & Juhava, 1971; Gothenborg & Pedersen, 1976).
Malene amphibolites and related anorthosites from Akugdlerssuaq, inner Godthåbsfjord, with komatiite affinities
Authors: Nutman A.P
Published: June 2021

Mapping by helicopter reconnaissance in 1976 (Allaart et al. 1977) and subsequent more detailed mapping in 1981 (Nutman, 1982) showed that there are several units of anorthosite with associated amphibolite on Akugdlerssuaq, inner Godthåbsfjord. The anorthosite and amphibolite units are interspersed with units ofstrongly deformed Amitsoq gneisses (identified by the presence of basic dyke remains and by enclaves of banded iron formation) sheeted by younger gneisses. Most of the contacts between anorthosite and amphibolite units and the Amitsoq gneisses are clearly tectonic, whilst the remaining contacts could also be tectonic or are modified primary contacts (Nutman, 1982). The younger gneisses are of late Archaean age (Bridgwater & Nutman, unpublished Rb-Sr isotopic data).
Uranium exploration in the Qagssiarssuk area, South Greenland
Authors: Nyegaard P
Published: June 2021

FolIowing the promising results of the Syduran project (Armour-Brown et al., 1984) a spin-off project Sydex was initiated in April 1984. The project is financed under the Ministry of Energy's Research Programmes 1984 and field work was carried out in several areas in South Greenland this summer (Armour-Brown & Wallin, this report). This contribution describes the work in the Qagssiarssuk area (fig. 20). In connection with the prospecting a geophysical survey was also carried out (Thorning & Boserup, this report). The main objects of the field work were to prospect the granite and sandstone area west of Qagssiarssuk between Tunugdliarfik and Nordre Sermilik (fig. 25) by ground scintillometry and water sampling. The major fauIt zones and adjacent areas together with the sandstonel granite unconformity were investigated especiaIly. Water samples from both lakes and streams were collected to test the usefulness of the method in this very poorly exposed area. Pitchblende and other uranium mineral occurrences have previously been found in major fault zones in the western part of the area (fig. 25) (Armour-Brown et al., 1983). Radioactive thorium-dominated dykes have also been found (Hansen, 1968; Armour-Brown et al., 1982). Stream-water and sediment samples with anomalously high uranium are located within the prospected area (Armour-Brown et al., 1982).
Determination of ice thickness by magnetic methods at Nordbogletscher, South Greenland
Authors: Thorning L
Published: June 2021

The topographic relief hidden under glaciers and the Inland Ice plays an important role in the study of ice dynamics, and several methods have been applied to map the subglacial surface of the Inland Ice in areas of interest for hydropower investigations. Radar-echo soundings or electromagnetic reflection methods (EMR) have often given good results, but have largely failed over the western rim of the ice cap, where inhomogenities in the form of melted and refrozen layers, water bodies, and cracks in the ice scatter the radar wave to such an extent that no useful echo is returned. In the summer of 1984 the author was in South Greenland for other purposes (Thorning & Boserup, this report), and it was decided to attempt to determine the ice thickness by magnetic profiling on the ice surface. Magnetic field measurements are not affected by the physical properties and structure of the ice, and thus it should theoretically be possibie to obtain results near the rim of the ice cap, where the EMR method has failed. Whether results could be obtained would depend on limiting factors such as the magnetic properties of the underlying rocks, instrument capabilities, sensitivity of correction and modelling methods, and the general ambiguity of potential field methods.
The Silurian turbidite sequence of the Peary Land Group between Newman Bugt and Victoria Fjord, western North Greenland
Authors: Larsen P.-H , Escher J.C
Published: June 2021

Several lithological units of the Silurian Peary Land Group show a remarkable continuity along the E-W trending basin axis, but pronounced lateral facies changes occur N-S across the basin. An approximately 4000 m thick sequence of turbidites to the north in the deep-water basin represents the time equivalent of about 1065 m of turbidites, slope sediments and platform carbonates at the basin margin to the south. Ellesmerian regional deformation affected the northern part of the area showing a progressive increase of deformation of the deep-water sequence from south to north. The general strnctural pattern suggests a lithological anisotrophy within the upper part of the crnst with a buried carbonate shelf to the south bounded by an escarpment towards a deep silicic1astic basin to the north. The difference in total thickness of the Llandovery to Lower Ludlow sedimentary sequence between the south and north supports this hypothesis.
Zinc mineralisation at Navarana Fjord, central North Greenland
Authors: Jakobsen U.H , Steenfelt A
Published: June 2021

A 5-7 m wide vein of calcite intersecting Cambrian dolomite at the west coast of Navarana Fjord contains a 1 m wide breccia zone in which massive sphalerite constitutes the matrix. The mineralisation is hydrothermal and related to tectonic movements. Bitumen occurs in the breccia zone and it is suggested that the zinc and the hydroearbons were transported together in the mineralising fluid. The sphalerite mineralisation is seen as one expression of a major zine mineralising event indieated by a reconnaissanee stream sediment survey.
The tectonic framework of the Precambrian shield of Greenland A review of new isotopic evidence
Authors: Kalsbeek F
Published: June 2021

There is now reliable isotopic evidence that most of the crystalline basement of Greenland consists of Archaean (>2500 Ma) rocks: only in the Ketilidian mobile belt of southemmost Greenland no Archaean rocks have yet been found. Proterozoic orogenic activity was widespread in the Nagssugtoqidian and Rinkian mobile belts of central and northem West Greenland, and peaked at c. 1850 Ma. There is some evidence that the Nagssugtoqidian mobile belt may define the boundary between two once separate Archaean continental plates and it is possibie that comparable plate boundaries also exist elsewhere in Greenland.
Systematics and mode of life of a new Silurian Clisospira (Mollusca) from North Greenland
Authors: Peel J.S
Published: June 2021

Clisospira ellitsgaardi sp. nov. is described from the Cape Schuchert Formation (Early Silurian) of Washington Land, western North Greenland. The cancellate ornamentation of the sinistrally coiled molluscan shell is produced by the interference of successive crenulate growth lamellae. The wide frill of C. ellitsgaardi may have hindered sinking into soft bottom sediment or increased shell stability by increasing the surface area of the underside of the shell. The strongly tangential aperture probably indicates that C. ellitsgaardi effectively clamped its shell against the substratum when disturbed.
Occurrences of anorthositic rocks in the reworked Archaean basement in the Umanak area, central West Greenland
Authors: Andersen M.C , Pulvertaft T.C.R
Published: June 2021

The main occurrence of anorthositic rocks in the Umanak area is the Tunulik sheet, a body up to 300 m thick with an areal extent of about 80 km2. The sheet is a composite body, consisting of blocks of crudely foliated anorthosite and leucogabbro 1-3 m in size in a granitic gneiss matrix. The blocks are jumbled together with no systematic distribution of blocks with different colour indices and no preferred orientation of the internal foliation within the blocks. The blocks are composed mainly of plagioclase, with small amounts of hornblende and biotite. The plagioclase shows patchy zoning; the composition is in the range An82-68. The dark minerals tend to be clustered in parallel schlieren. Epidotisation has given many blocks a yellowish colour. Textures are metamorphic. Both quartz- and nepheline-normative compositions are represented in the anorthositic blocks; it is suspected that compositions were modified with respect to Si, and possibly also Na and K, during metamorphism and incorporation in the granitic host. In addition to the Tunulik sheet, there are several small occurrences of anorthositic rocks in the Umanak area. These differ from the Tunulik sheet only in the fact that the anorthositic blocks in the minor occurrences are hosted in granodioritic-tonalitic gneiss no different from the country gneisses in the area, whereas in the Tunulik sheet the matrix gneiss is granitic.
Tungsten exploration in the southern part of the Godthåb area, West Greenland
Authors: Appel P.W.U
Published: June 2021

Recent work by the Geological Survey of Greenland (GGU) in the Godthåb (Nûk) area has revealed a large tungsten province with extensive scheelite mineralisation in the Archaean Malene supracrustal rocks (Appel, 1983, 1984). In the area between Godthåb and Frederikshåb Isblink several large supracrustal amphibolite belts occur (fig. 1). These are presumably of the same age as the scheelite-bearing Malene amphibolites of the Godthåb area (Bridgwater et al., 1976). It was therefore decided to carry out a regional stream-sediment sampling programme in the area south of Godthåb, and this was accomplished in the summer of 1985. The aim of the programme was mainly to find scheelite, but the samples will subsequently be analysed for a number of other elements such as Cu, Pb and Mo. The folIowing report is mainly based on field observations. Laboratory work is confined to X-ray determination of scheelite in three heavy mineral concentrates.
Reconnaissance dating of Archaean rocks from South-East Greenland
Authors: Escher J.C , Kalsbeek F , Larsen O , Nielsen T.F.D , Taylor P.N
Published: June 2021

A major project of geological investigations in South-East Greenland is planned for 1986 and 1987 with the aim of producing sheet 14 of the 1:500000 geological map series covering Greenland. The northern part of the map sheet is occupied by the Nagssugtoqidian mobile belt, and the southern part consists mainly of Archaean rocks. Because of difficulties of access, the Archaean part of the area is poorly known. Geological reconnaissance has been carried out by Bridgwater & Gormsen (1969), and, as a preparation for the 1986 and 1987 expeditions, by Escher & Nielsen (1982, 1983) and Nielsen & Escher (1985). This report presents reconnaissance Rb-Sr and Pb-Pb whole-rock age determinations from the Archaean part of the map sheet.
Oil geological studies in central East Greenland
Authors: Piasecki S , Marcussen C
Published: June 2021

Field work undertaken in central East Greenland during August 1985 was a follow-up of the oil geological studies by GGU expeditions to Jameson Land in 1982 and 1983 (Surlyk, 1983; Surlyk et al., 1984a). Three major subjects were covered by the field work. The Permian-Triassic boundary was studied along the western margin of the Jameson Land basin (Surlyk et al., 1984b). A series of closely sampled sections along the exposures of the eastern part of the Schuchert Dal was completed. The sampled material will be analysed with respect to source rock quality, maturity and stratigraphy. Secondly, the analysis of the regional maturity in southern Jameson Land based on the material from the 1982-83 expeditions indicates a specific surface maturation pattern (Piasecki, 1985; Thomsen, 1985) which had to be confirmed or rejected by analyses of further material from localities throughout the area. New material was collected along Hurry Inlet and in the southern llnd western parts of Jameson Land. Maturity studies will be supplemented by stratigraphical and geochemical analyses at these localities. The third target of the field work was to start oil geological studies of the area north of Kong Oscar Fjord, and to locate drill sites for shallow-core drilling in immature potential source rocks. The island of Traill ø was visited for two days of helicopter reconnaissance. Wollaston Forland was visited for two days at the end of the season in co-operation with geologists of a British Petroleum (BP) party working in this area. Material was collected for preliminary source rock studies and biostratigraphy.
Tove Birkelund
Authors: Henriksen N
Published: June 2021

During the editing of this volume it was announced that Professor Tove Birkelund had died in Copenhagen on 24th June 1986 at the early age of 57 years. Tove Birkelund was for several decades a central figure in Greenland geology, maintaining an involvement with Greenland begun during her earliest days as a geologist. Although employed by the University of Copenhagen, her work in Greenland was at all times closely associated with GGU.
Early Ordovician trilobites from the Wandel Valley Formation, eastern North Greenland
Authors: Fortey R.A
Published: June 2021

A small trilobite fauna is described from the Wandel Valley Formation of Kronprins Christian land, eastern North Greenland. It has a specific composition identical to the fauna from the Catoche Formation, western Newfoundland, which is typical of the shallow water bathyurid biofacies of the eastern part of the Ordovician Laurentian palaeocontinent. The fauna is of early Ordovician age, trilobite Zone H, equivalent to the early Arenig.
Nordenskiöld or Nordenskjöld?
Authors: Higgins A.K
Published: June 2021

The Nordenskiöld Bjerg Subgroup takes its name from Nordenskiöld Bjerg in Canning Land, East Greenland, but the mountain takes its name not from A. E. Nordenskiöld or his son G. E. A. Nordenskiöld, but from Otto Nordenskjöld. All were Swedish scientists, commemorated by place names in Greenland. The features named after them, however, have been variously spelt due to uncertainty as to which of them was being honoured, and also variations in orthographic practice.
Tetinia (Trilobita) from the late Silurian of western North Greenland
Authors: Lane P.D , Larsen P.-H , Escher J.C
Published: June 2021

A late Silurian trilobite, Tetinia sp., is described from the Wulff Land Formation of the Peary Land Group in western North Greenland. The record is the first in Greenland of a genus otherwise only known from Czechoslovakia, Gotland, Podolia and Britain.
Geochemical exploration in central and western North Greenland
Authors: Jakobsen U.H , Stendal H
Published: June 2021

The 1985 geochemical exploration programme in central and western North Greenland completed the present geochemical exploration programme. A total of 424 stream sediment samples were collected during the 1985 field season. The reproducibility of drainage sampling is reasonably good for the elements Ba and Zn. Follow-up of anomalous Ba and Zn values from drainage samples collected in 1984 has not revealed any new mineralised localities. The high contents of Ba and Zn are interpreted as associated with: (1) pyrite-bearing strata, and/or (2) carbonate conglomerate, and/or (3) a higher general content of these elements in some lithostratigraphic units. A known zinc mineralisation in Navarana Fjord, eastern Freuchen Land, contains baryte in addition to sphalerite.
Geochemical trends in central and western North Greenland
Authors: Steenfelt A
Published: June 2021

Geochemical maps and geochemical cross-sections, based on chemical analyses of the < 0.1 mm fraction of stream sediment samples collected at a density of approximately 1 sample per 30 km2 in central and western North Greenland, show that the distribution patterns for the major elements and some trace elements reflect the main lithological units of the North Greenland Palaeozoic platform and trough. By contrast the distribution patterns for S and Sr are different. High S values are correlated with zones of tectonic activity and are thought to indicate migration of H2S along faults. High Sr values are correlated with evaporitic rocks in the platform sequence and with deep sea carbonates. High BaO values occurring along the Silurian platform margin and in the Ordovician platform-slope sequence are the result of Ba enrichment in the sedimentary environment, combined with epigenetic vein-type baryte mineralisation.
Ti-rich plagioclase-phyric dykes of southern West Greenland
Authors: Hall R.P , Hughes D.J , Friend C.R.L
Published: June 2021

The investigation of Proterozoic basic dykes in southern West Greenland stemmed from the programme of systematic mapping of the Archaean craton in that region by the Geological Survey of Greenland (GGU). This work began in the southern Frederikshåb region in the early 1960s (Jensen, 1968, 1969) and progressed northwards, from bases in the Fiskenæsset (Kalsbeek & Myers, 1973; GGU, 1976), Godthåb (Allaart et al., 1977) and Sukkertoppen areas (Allaart et al., 1978). The results of most of this mapping work were summarized by Bridgwater et al. (1976) and compiled onto a 1:500 000 scale geological map sheet by Allaart (1982). The distribution of the major Proterozoic dykes which cut the entire region is shown on this map. While the basic dykes are individually minor intrusions, many are up to 50 metres wide and continuous for several tens of kilometres, and collectively they represent a major magmatic event. As many of the Archaean terrains of the world possess Proterozoic basic dyke swarms, their compositions are crucial to a correlation of events from one craton to another and to an understanding of crustal and mantle evolution after the world-wide late Archaean sialic crust-forming event.
An ice-sampling programme in the Thule area, North Greenland
Authors: Reeh N , Thomsen H.H
Published: June 2021

A glaciological programme was carried out as part of the NORDQUA 86 expedition to the Thule area, Nbrth Greenland, from 7 to 24 August 1986. The expedition included researchers from the five Nordic countries and Great Britain and was organised by the Geological Museum, Copenhagen (Funder, in press). The expedition had a Quaternary geological programme, as well as a glaciological programme dealing with the climatic history and ice-sheet dynamics before and during the last Ice Age in the area.
Introduction of new computing facilities at the Geological Survey of Greenland
Authors: Thorning L
Published: June 2021

From a cautious start in the use of computers in the early 1970s, the Geological Survey of Greenland has developed complex and varied uses of modern computer facilities for both scientific and administrative tasks. GGU's first computer installation, a noisy TTY connected to the Computing Centre of Copenhagen University by a 110 baud telephone modem, was a selfservice facility which was not easy to use. Over the years, first with use of a PDP-10 with just one Tektronix 4014 graphic terminal and later a succession of increasingly powerful PDP-11s with many terminals, GGU's in-house facilities just kept ahead of the ever increasing demand for computer services. At the same time a number of programs for special tasks were developed on external facilities, because they required larger computers or special facilities. In the 1980s the demands on the computer facilitiesrequiring many different types of programs, including word processing, had grown so large that GGU's in-house system could no longer handle them satisfactorily. A major reorganisation was required, and consequently activities were divided between personal computers (PCs; mainly administrative) and a new central computer (mainly scientific). This development took place in late 1986 with the purchase of 17 new personal computers and a new central computer with accessory peripheral equipment. This has allowed an increasing integration of computer methods into GGU's activities. A brief summary is given below.
Reconnaissance aeromagnetic survey east of Disko Bugt, central West Greenland
Authors: Thorning L
Published: June 2021

The Geological Survey of Gre.enland plans a major aeromagnetic survey in the Disko Bugt region over the coming years. It has already been started with some introductory work in 1986 and 1987 (Knudsen el al., 1988). In this context, closed-file geophysical data were reviewed at GGU, and it soon became clear that good quality regional aeromagnetic data were lacking from the area and that the geological investigations would benefit from such data. Funds were not available for a systematic survey over the entire area, but in April 1987 a situation arose in which at least part of the area could be surveyed. Due to the change of plans for the aeromagnetic surveying of the GICAS project, described by Thorning el al. (1988), it was possibie to include one survey flight east of Disko Bugt. The measurements were made from the National Aeronauticai Establishment aircraft (CFNRC), which is a well equipped Convair-580 with very good navigational capabilities and a 3-axis magnetic gradiometer.
Basic rocks of the inner Fiskefjord area, southern West Greenland
Authors: Bengaard H.-J
Published: June 2021

During mapping for the Fiskefjord map sheet (64 V.1 N - 1:100000) observations were made on the basic rocks. Earlier reports on the mapping of the Fiskefjord area have been given by Garde (1984, 1986) and Garde et al. (1987), and the reader is referred to these for more detailed descriptions af the general geology. Most of the inner Fiskefjord area is made up of a variety af gneisses, correlated with the late Archaean Nûk gneisses. The most common type is a weakly banded, tonalitic gneiss, usually grey, sometimes with a Iilac tint. Metagranites and more mafic gneisses of dioritic to quartz dioritic composition form mappable units as well as bands of inclusions in the tonalitic gneisses. The gneisses show intrusive relationships to a group of basic and ultrabasic rocks, mainly two-pyroxene basic granulites (named 'pyribolites' by Berthelsen, 1960) with minor dunite and norite. Small amounts of metasedimentary gneiss are associated with the norite.
Greenland ice cap aeromagnetic survey 1987: completion of the survey over the southern end of the Greenland ice cap
Authors: Thorning L , Bower M , Hardwick C.D , Hood P
Published: June 2021

The Geological Survey of Greenland (GGU), the Geological Survey of Canada (GSC), and the National Aeronautical Establishment (NAE) of the National Research Council of Canada are cooperating in the GICAS project. The objective of the project is to achieve a regional, aeromagnetic coverage of the Greenland ice cap, and to produce magnetic anomaly maps for use in research on the large scale geological structures. Field work was carried out in 1983, 1984, and 1985 (Thorning et al. , 1984, 1985, 1986). The work reported in this note was originally planned for April 1986, but for technical reasons it had to be postponed until April 1987. Consequently, the subsequent processing of all the data into a regional magnetic anomaly map has been correspondingly delayed.
Construction and testing of a lightweight radar for ice-thickness determinations on glaciers in the Pâkitsoq area, central West Greenland
Authors: Thorning L , Hansen E
Published: June 2021

Although the helicopter-borne EMR surveys described in Thorning & Hansen (1988) resulted in excellent results from most of the catchment area of interest for the hydropower plant planned for Jakobshavn, there are still some local areas, such as the glacier lobes and ice-falls; where no meaningful data could be obtained. In the autumn of 1986 it was decided to construct a monopulse ice radar for use in such areas.
The Silurian shales of central and western North Greenland: evaluation of hydrocarbon source rock potential
Authors: Christiansen F.G , Nøhr-Hansen H
Published: June 2021

The Silurian shales of central and western North Greenland form a more than 400 m thick succession which contains some potential hydrocarbon source rock intervals. Deposition of these organic-rich units was restricted in both time and space and potential source rocks only formed when and where black shales covered wide areas of sballow-water carbonates. Such deposition started in the middle Llandovery in Washington Land and continued tboughout the region in the late Llandovery. Neither the Wenlock nor the Ludlow shales contain sufficient organic matter to be considered as potential source rocks. The potential source rocks are dominated by oil-prone organic matter (large amorphous kerogen particles, mainly type Il) and typically show TOC values between 2% and 6%. The generative potential of immature to early mature samples is high with values up to 30 mg Hag rock. A drastic increase in thermal maturity of surface rocks is observed from south to north and most of the potential drainage area is thermally mature to postmature. This leaves only few chances of finding trapped hydrocarbons sourced by Silurian shales in North Greenland.
Review of the Survey's activities in 1988
Authors: Ghisler M.
Published: June 2021

During 1988 GGU started two major field projects in Greenland, one in North-East Greenland, and another in West Greenland in the Disko Bugt area. In addition petroleum geological investigations in Jameson Land and glacio-hydrological studies in West Greenland continued. A total of 84 participants were engaged in the field work. The scientific and technical staff at GGU in Copenhagen continued research on material collected in Greenland; total staff including administrative personnel numbers at present 108. A 10 per cent reduction of the staff is forecast over the next four years, combined with an additional reduction of the budget by 14 per cent. Accordingly, decreasing activity in both field work in Greenland and laboratory work in Copenhagen is expected. This development, rather similar to the trend in other western European geological surveys, willlead to a relatively greater engagement in applied geological projects and to less basic geological research. The Act on Mineral Resources in Greenland was revised in 1988 by agreement between the Danish Parliament and the Greenland Home Rule Authority. In accordance with this, all revenues from mineral exploitation in Greenland up to 500 million kroner per year wiIl be distributed with 50% to the Danish State and 50% to the Greenland Home Rule Authority, independent of the annual capital transfers from Denmark to Greenland. In addition the Home Rule Authority's access to, insight into, and influence on the Danish administration of Greenland's mineral resources (including GGU) are increased in various respects. The agreement is valid until at least 1995.
Reinvestigation of the Cretaceous boundary fault in Sarqaqdalen, Nûgssuaq, central West Greenland
Authors: Pulvertaft T.C.R
Published: June 2021

A reinvestigation of the major fauIt in Sarqaqdalen was undertaken in 1988 in response to a renewed interest in the style and timing of the whole fault system that marks the easterly limit of Cretaceous sediments in central West Greenland. This interest stems in turn from the reinterpretation ofseismic lines from the 1970s that has recently been initiated in GGU (Chalmers, 1988; 1989). Dating of seismic sequences isinfiuenced greatly by what ean be learnt from the nearest onshore outcrops, for example proven unconformities in onshore sequences, and demonstrable relationships between sedimentation and fauIt movements.
Sedimentological studies in the Upper Cretaceous coal-bearing strata of southern Nûgssuaq, central West Greenland
Authors: Midtgaard H , Olsen T
Published: June 2021

During the 1988 field scason coal-bearing strata in the Upper Cretaccous Atanc Formation an southern Nûgssuaq, West Greenland (fig. I) were investigated in order to describe and interpret the sedill1cntological features. an the basis af this, it was hoped that a more refined synthesis of the regional geology could bc made. Previous work in the area has dealt mainly with thc dating of the formation (earlier references in Rosenkrantz, 1970), its assemblage of plant fossils (Heer, 1983; Seward, 1926), marine macrofossils (Steenstrup, 1874; Ravn, 1918) and its coal potential and petrography (Shekhar et al., 1982). The general depositional environment was discussccl by Sehiener (1975) and Henderson et al. (1976). The GGU coal project (Shekhar er al., 1982) adopted the models presentcd in these papers but despite impressive field work did not shed much new light on the origin of these sediments.
Improved accumulation measurements on Glacier ICG14033 near Nuuk/Godthåb, West Greenland
Authors: Braithwaite R.J , Thomsen H.H
Published: June 2021

Glacier 1CG14033 is a small (1.1 km2 ) glacier located in the Kangerluarsunnguaq or Buksefjorden basin, which is a possibie site for a hydropower station to supply energy to Nuuk/Godthåb (fig. 1). Glaciers only occupy 1-2% of the basin area (Weidick & Thomsen, 1983), but glaciological measurements have been made since 1982 to investigate the possibie effects of glaciers on runoff and to contribute to GGU's programme of regional glaciology.
Shallow core drilling of Upper Permian and Upper Triassic – Lower Jurassic potential reservoir rocks in central East Greenland
Authors: Christiansen F.G , Stemmerik L
Published: June 2021

The aim of the 1988 shallow core drilling programme was to obtain unweathered and statistically representative samples of potential reservoir rocks to evaluate their diagenetic history. In the concession area held by ARCO (fig. 1) the youngest rocks expected to form a subsurface reservoir are the Upper Triassic - Lower Jurassic Kap Stewart and Neill Klinter Formations (Surlyk et al., 1986b; Stemmerik, 1988). At present, however, most interest is concentrated on the Upper Permian Wegener Halvø Formation (Surlyk et al., 1986a; Hurst et al., 1989) and, consequently, the programme focused on this formation in the type area (fig. 2). Additional drilling was carried out through the Kap Stewart Formation at a location dose to Constable Pynt (fig. 1).