bluuebunny/crossref_metadata_2025 huggingface dataset:
The Navarana Fjord Member (new) - an Upper Llandovery platform derived carbonate conglomerate
Authors: Surlyk F , Ineson J.R
Published: June 2021

A new lithostratigraphical unit, the Navarana Fjord Member of latest Llandovery age, is formally erected in this paper. It consists of an up to 80 m thick sequence of amalgamated carbonate conglomerate beds. The member is presently known from the east and west coast of Navarana Fjord, central North Greenland. It rests or, Silurian carbonate platform to the south. To the north of the platform margin scarp it rests on and interfingers with turbidites of the Merqujôq Formation. The member is inc!uded in the Merquj6q Formation and forms an important marker reflecting the final foundering of the outer carbonate platform.
Additions to the lithostratigraphy of the Peary Land Group (Silurian) in western and central North Greenland
Authors: Larsen P.-H , Escher J.C
Published: June 2021

New information is given on the areal extent, thickness, age and general field occurrence ofthe Silurian Peary Land Group. One new formation (Nyeboe Land Formation), three new members (Kap Brevoort, Hand Bugt and Castle Ø) are added to the established stratigraphy. The Lauge Koch Land Formation, Repulse Havn Member and Hendrik Ø Member are redefined.
Cambrian - Lower Silurian stratigraphy in the fold and thrust zone between northern Nyeboe Land and J. P. Koch Fjord, North Greenland
Authors: Davis N.C , Higgins A.K
Published: June 2021

Brief description is given of observations on the Cambrian - Lower Silurian outer shelf and slope deposits of central and western North Greenland. A provisional correlation is proposed between various units of the shallow marine Buen Formation and units of the deep-water Polkorridoren Group.
Late Silurian plant megafossils from the Peary Land Group, North Greenland
Authors: Larsen P.-H , Edwards D , Escher J.C
Published: June 2021

Late Silurian plant megafossils including HostinelIa and Salopella are described for the first time from Greenland. The plants are recovered from Ludlow strata within the deep-water turbidites of the Peary Land Group in central and western North Greenland. The remains are among the oldest known terrestrial plant megafossils. The plant assemblage is briefly compared with assemblages of Silurian age elsewhere and its palaeo- geographic significance is evaluated.
Archaean U-Pb zircon ages from the Scoresby Sund region, East Greenland
Authors: Hansen B.T , Higgins A.K , Borchardt B
Published: June 2021

U-Pb analyses on zircons are reported for two rock colleetions from infracrustal complexes within the East Greenland Caledonian fold belt in the Scoresby Sund region. Calculated minimum ages range from 2800 to 2965 Ma, and are the oldest ages obtained in the region using this method.
Early Tertiary volcanic rocks from eastern Disko and south-eastern Nûgssuaq
Authors: Pedersen A.K , Larsen L.M
Published: June 2021

As part of an integrated study of the interaction between sedimentary and volcanic facies in the Cretaceous-Tertiary West Greenland basin, early Tertiary extrusive and intrusive basic igneous rocks have been investigated in eastern Disko and south-eastern Nûgssuaq (fig. 1). The volcanic activity started in the early Tertiary. It was centred in the western regions of Disko and Nûgssuaq and west of the present land areas, and consequently western Disko and western Nûgssuaq have a thick and complete volcanic succession, the Vaigat and Maligât Formations (Hald & Pedersen, 1975; Pedersen, 1975a, 1985). The coeval deposits in the eastern part of the basin are clastic sediments of the Upper Atanikerdluk Formation (Koch, 1959). With time, the volcanic deposits prograded eastwards, and eventually the whole area was covered by a coherent basalt plateau. The present study attempts to extend the established volcanic stratigraphy from western Disko and the geological map sheets 1:100 000 Qutdligssat (published in 1976) and Mellemfjord (published in 1987) into eastern Disko and eastern Nûgssuaq where volcanic rocks and sediments interfinger.
Reconnaissance for noble and base metal mineralisation within the Precambrian supracrustal sequences in the Ivigtut–Kobberminebugt region, South-West Greenland
Authors: Secher K , Kalvig P
Published: June 2021

The field programme in the Ivigtut-Kobberminebugt region is a continuation of the investigation of gold occurrences in the Tartoq Group greenstones, just north of the present area (Appel & Secher, 1984; Appel, 1984). The region was mapped by GGU in the late 1950s and early 1960s (Henriksen, 1969; Berthelsen & Henriksen 1975; Harry & Pulvertaft, 1963). The Tartoq and the Ketilidian supracrustal belts were described (Allaart, 1976; Bridgwater et al., 1976); they form regional curved structures around the Arsuk Basin. The major part of the supracrustal sequences south of the Tartoq Group units is expected to be of Ketilidian (Proterozoic) age and deformation. However, some layers in the Nunarssuit peninsula in the southernmost part of the region are undated and might be older (Bridgwater et al., 1973; Appel & Secher, 1984). The investigation was focussed on the supracrustal sequence between Arsuk Fjord and Nunarssuit (fig. 1), with special emphasis on the areas neighbouring the known gold showings at Josva Mine (worked 1910-15) where discrete grains of electrum and gold in the bornite ore were reported by Harry & Den (1964). In the Kînâlik peninsula a skarn boulder with a few grains of gold included in cha1copyrite has been reported by Kryolitselskabet Øresund A/S (Nielsen, 1976). The work was based on reconnaissance rock sampling of lithologies and mineral showings within the supracrustal sequences, with particular attention given to transitions between sedimentary and vo1canic suites and to structural breaks in order to locate potential sources of noble metals.
Late Bathonian to Early Oxfordian dinoflagellate cyst stratigraphy of Jameson Land and Milne Land, East Greenland
Authors: Smelror M
Published: June 2021

The stratigraphic distribution of Upper Bathonian to early Middle Oxfordian dinoflagelIate cysts from localities in Jameson Land and in Milne Land, East Greenland, is evaluated. Using the range of selected species, their earliest appearances andlor extinction, six dinoflagelIate cyst zones and five subzones are proposed for the upper Middle and lower Upper Jurassic succession of central East Greenland. The proposed zonation scheme is correlated with the ammonite zonation of the investigated interval. Two new species, Chytroeisphaeridia grossa sp. nov. and Escharisphaeridia laevigata sp. nov. are formally described.
Etah meta-igneous complex and the Wulff structure: Proterozoic magmatism and deformation in Inglefield Land, North-West Greenland
Authors: Dawes P.R
Published: June 2021

A hitherto uninvestigated collection of crystalline rocks from north-eastem Inglefield Land (c. 79°N) allowanew interpretation of the Precambrian geology of the region. The majority of the samples - high-grade basic, intermediate and granitoid rocks - are referred to the Etah meta-igneous complex, which has been shown to be mid-Proterozoic in age in the type area in south-western Inglefield Land. In areas of high deformation there is a gradation from massive rocks of igneous aspect into folded and variably migmatised gneisses. Thus the magmatic complex provides a gauge of the nature and intensity of Proterozoic (Hudsonian) deformation and metamorphism. In Inglefield Land Proterozoic deformation produced different structural styles; thus in the north-east the Wulff structure - a large-scale refolded isoclinal structure - characterises a region that lacks an obvious preferred regional foliation direction, while in the south-west, linear E-W trending belts with steep dips dominate the structural pattem. The Proterozoic evolution is outlined from the formation of the Etah Group, a supracrustal sequence that pre-dates the Etah meta-igneous complex, to uplift, peneplanation, deposition and magmatism in the late Proterozoic. Inglefield Land is not part of the Rinkian mobile belt of West Greenland, and it is stressed that the obvious continuation of the Proterozoic geology is into Ellesmere Island.
Geological reconnaissance in the Precambrian basement of the Atâ area, central West Greenland
Authors: Knudsen C , Appel P.W.U , Hageskov B , Skjernaa L
Published: June 2021

Geological reconnaissance was carried out in July 1987 as part of regional geological investigations planned for 1986-1992. The field work was carried out from three field camps with logistic support from GGV cutter 'J. F. Johnstrup', a helicopter and a rubber dinghy. The mapping was made on aerial photographs.
Stream sediment sampling in the Atâ area, central West Greenland
Authors: Appel P.W.U , Knudsen C
Published: June 2021

In 1982 scheelite was identified in stream sediments in the: Nuuk/Godthåb area, about 600 km south of Atâ. Subsequentlya regional stream-sediment programme was carried out in the Nuuk area from 1982 to 1987 as a result of which scheelite was found to be quite abundant in the 3800 m.y. old Isukasia supracrustalrocks as well as in the 3300 to 3000 m.y. old Malene supracrustal sequence (Appel, 1988). It was also recognised that there is a close correlation between the number of scheelite grains and the gold content of the heavy mineral concentrates in the Nuuk area (Appel, 1988). In the Ata area (fig. 1) extensive outcrops of supracrustal rocks are found. In these supracrustals, which have been metamorphosed to greenschist and amphibolite facies, abundant sulphide-rich horizons are found, as well as sulphide-bearing breccia zones with appreciable gold contents (Knudsen et al., 1988). During the 1987 field season geological reconnaissance mapping was carried out in two of the supracrustal areas and the gneiss-granite complex enclosing the supracrustal rocks ·was investigated (Knudsen et al., 1988). A limited programme of stream-sediment sampling was carried out in the Atâ area, where stream sediment samples were collected in all the main streams draining the supracrustal rocks.
Investigations of Tertiary volcanic rocks along the south coast of Nûgssuaq and in eastern Disko, 1987
Authors: Larsen L.M , Pedersen A.K
Published: June 2021

As a continuation of an integrated study of sedimentary and volcanic facies in the Cretaceous to Tertiary West Greenland basin (G. K.Pedersen, 1987; A. K. Pedersen & Larsen, 1987) early Tertiary volcanic rocks were studied in 1987 along a NW-SE trending composite section, about 120 km in length; on Niigssuaq and Disko. The study attempts to establish and describe lithostratigraphic volcanic units in the Tertiary volcanic formations, and through a combination of field mapping, photogrammetry and geochemistry to establish chronostratigraphic horizons through the early Tertiary deposits of the region. In this respect it is essential to identify the same eruptive units as subaeriallava facies and as subaqueous lava or hyaloclastite facies, and to trace subaerial tufts throughout the area. In the first part of the season localities along the Vaigat coast of Nûgssuaq from Kugssinerssuaq in the east to Nûssap qâqarssua in the west were investigated. In the second part of the season very poorly known areas in the western and southem part ofthe Kvandalen region on east Disko were investigated. The field work was supported by the Arctie Station in Godhavn and its cutter Porsild as well as by GGU's cutter J. F. Johnstrup.
Corundum crystals with blue-red colour zoning near Kangerdluarssuk, Sukkertoppen district, West Greenland
Authors: Garde A.A , Marker M
Published: June 2021

Results are presented of field work at a corundum locality near the head of Kangerdluarssuk, east of Maniitsoq/Sukkertoppen, West Greenland. The authors carried out geological mapping and sampling over four days in August 1987 to evaluate the quality of the corundum as a possibIe gemstone.
Border relations between the amphibolite facies Finnefjeld gneiss complex and granulite facies grey gneisses in the Fiskefjord area, southern West Greenland
Authors: Marker M , Garde A.A
Published: June 2021

The authors carried out geological mapping in August 1987 at the south-eastern boundary of the Finnefjeld gneiss complex around 65°N. The field work was supported by the GGU cutter 'J. F. Johnstrup'. Based on reconnaissance mapping in the 1950s Berthelsen (1951, 1957,1962) divided the Archaean gneiss terrain in the southem Sukkertoppen district between Godthåbsfjord and Søndre Isortoq into three major tectonic units: the Nordland, the Finnefjeld and the Alangua complexes. This division was also followed by Noe-Nygaard & Ramberg (1961).
Evolution and emplacement of Archaean terranes in the Kapisigdlit area, southern West Greenland
Authors: Friend C.R.L , Nutman A.P
Published: June 2021

In the Godthåbsfjord region, early Archaean Arnitsoq gneisses are found in association with the middle Archaean Nûk gneisses (McGregor, 1973). Early models of crustal evolution in the Godthåbsfjord region suggested that the Amitsoq gneisses were reworked in a major crustal accretion-differentiation event, which was marked by the injection of the voluminous Nûk gneisses (e.g. Bridgwater et al., 1974; McGregor, 1979; Moor- - bath et al., 1986). This event ,has been interpreted as having culminated in a granulite-amphibolite facies metamorphic event at c. 2800 Ma, which outlasted all significant ductile deformation (e.g. Wells, 1979; Coe, 1980).
Studies of the onshore hydrocarbon potential in East Greenland 1986-87: field work from 73° to 76°N
Authors: Marcussen C , Larsen P.-H , Nøhr-Hansen H , Olsen H , Piasecki S , Stemmerik L
Published: June 2021

The study of the Devonian to Cretaceous sequence in central and northem East Greenland was continued in 1987. Field work was carried out from early July to mid August covering the region between Ymer Ø and Hochstetter Forland (fig. 1). This was the second year of a two-year field work programme (Marcussen et al., 1987) which forms part of a regional programme comprising sedimentological, stratigraphic, structural, and petroleum geological studies of the sedimentary basin in central East Greenland (e.g. Surlyk, 1983; Surlyk et al., 1984, 1986a,b). Stordal in Hudson Land, which offers a naturaIlanding strip for STOL aircraft, was used as base camp for the 1987 expedition. The expedition group of 15 included four to five geological field parties and five supporting personnel, including a helicopter pilot and mechanie. In addition a five-man British-Danish East Greenland 'vertebrate-paleontological' expedition (Bendix-Almgreen, 1988) and a group from GGU planning the 1988 expedition to North-East Greenland were present. Two teams (led by P.-H.. Larsen and H. Olsen) studied the tectonics and sedimentology of the Devonian succession. Two teams (led by L. Stemmerik and S. Piasecki) investigated the Carboniferous, Permian and Triassic sedimentology of the region. The Jurassic and Cretaceous sequences were studied by two teams (led by S. Piasecki and in the late half of the season by H. Nøhr-Hansen). All the teams collected material for source rock analyses and a large number of samples were also collected for determining reservoir rock properties.
A pilot seismo-stratigraphic study on the West Greenland continental shelf
Authors: Chalmers J.A
Published: June 2021

Seismo-stratigraphic interpretation of seismic sections dating from the mid-1970s has disclosed the existence of four megasequences of sediments, the oldest of which has not previously been reported from West Greenland. The basins containing these sediments developed as a series of coalescing half graben, in which the main site of tectonic activity changed with time. A structural closure of sufficient size to contain interesting quantities of hydrocarbons, given suitable source rocks, reservoir and seal, is identified. The study has shown that the evaluation of the West Greenland Basin during the 1970s was inadequate, and that abandonment of exploration by the petroleum industry may have been premature.
The Morris Bugt Group (Middle Ordovician - Silurian) of North Greenland and its correlatives
Authors: Smith M.P , Sønderholm M , Tull S.J
Published: June 2021

The Morris Bugt Group, originally proposed in western North Greenland, is now extended across the whole of North Greenland. One new formation, the Kap Jackson Formation, is described; it includes two members, the Gonioceras Bay and Troedsson Cliff Members, which correspond to earlier formations of the same names. In the Washington Land - western Peary Land region the group comprises the Kap Jackson, Cape Calhoun and Aleqatsiaq Fjord Formations. The Børglum River and Turesø Formations of the Peary Land - Kronprins Christian Land region are here added to the group. New data on the age of the formations based on conodont biostratigraphy are given, and correlations with Arctic Canada, East Greenland and Svalbard are discussed.
Stratigraphy and hystricurid trilobites of the Christian Elv Formation (Lower Ordovician) of western North Greenland
Authors: Fortey R.A , Peel J.S
Published: June 2021

The Christian Elv Formation (Early Ordovician) of Daugaard-Jensen Land, western North Greenland, is formally proposed and recognised from southern Hall Land, in the east, to western Ellesmere Island in the Canadian Arctic Islands, to the west. The formation in its type section includes a shallow water trilobite fauna suggesting a mid-Tremadoc age; conodonts indicate the Rossodus manitouensis Zone af the North American Midcontinent Realm. Two species af hystricurid trilobites are present, of which one, Hystricurus scrofulosus, is dcscribed as a new species. The distribution of Hystricurus followed the early Ordovician palaeo-equator and was not confined by palaeocontinental boundaries. Paraplethopeltis is considered to be a subgcnus af Hystricurus.
Discovery of andesite tuffs with graphite from the Vaigat Formation of south central Nûgssuaq: stratigraphical implications
Authors: Pedersen A.K , Larsen L.M , Ulff-Møller F
Published: June 2021

During helicopter reconnaissance in 1987, one of us (P. U.-M.) found patches of poorly exposed tuffaceous rocks within the Vaigat Formation on the west side of Ilugigsoq valley north of Auvfarssuaq (fig. 1). Subsequent investigation under the microscope revealed that the tuft consists of graphite-rich andesite very similar to the most abundant tuft type described from the Abraham Member of the Agatdal Formation by Pedersen (1978). The discovery of the new locality with this rare rock type led to a helicopter-based reconnaissance in the Ilugigsoq and Qilakitsoq valteys in the summer of 1988 by two of us (A. K. P. & L. M. L.) in order to trace this possibie marker horizon and put it into a stratigraphical context. Similar tufts were found at two localities described below. Graphite andesites are known from other localities on Nûgssuaq and Disko, and notes on these are also given below.
Caledonian and pre-Caledonian geology of the region between Grandjean Fjord and Bessel Fjord (75°–76°N), North-East Greenland
Authors: Henriksen N , Friderichsen J.D , Strachan R.A , Soper N.J , Higgins A.K
Published: June 2021

The area between Grandjean Fjord and Bessel Fjord was the focus in 1988 of regional geological investigations and 1:500000 mapping during the North-East Greenland project (Henriksen, 1989). The greater part of the area forms part of the East Greenland Caledonides and can be divided into three distinct rock groups: infracrustal gneisses and granites of possibie Archaean or early Proterozoic origin; a metasedimentary sequence which has probably suffered both mid-Proterozoic and Caledonian migmatisation and metamorphism; and the late Proterozoic Eleonore Bay Group, a thick sedimentary sequence which has undergone amphibolite facies Caledonian metamorphism in its lower parts and is intruded by Caledonian granites. Aspects of the stratigraphy and sedimentology of the Eleonore Bay Group are described by Sønderholm et al. (1989); only the structures affecting the sequence are described here.
Stratigraphic and sedimentological studies of the Eleonore Bay Group (Precambrian) between 73° 30' and 76°N in East Greenland
Authors: Sønderholm M , Collinson J.D , Tirsgaard H
Published: June 2021

As part of the North-East Greenland Project 1988- 1990, a sedimentologieal study of the Precambrian Eleonore Bay Group between Grandjean Fjord and Bessel Fjord (75°-76°N) (fig. 1) was planned to start in 1988 with one two-man team and to eontinue in 1989 with two teams. This area was last visited in 1955 when Sommer (1957) as a member of Lauge Koeh's expeditions to East Greenland earried out the mapping. This work, however, only dealt with stratigraphie and teetonic problems, and sedimentological data, apart from gross lithologies, were not recorded. Unfortunately, the field work of 1988 quiekly revealed that the sediments had suffered from a relatively strong metamorphie recrystallisation, and henee it was generally not possibie to earry out detailed sedimentologieal work in this arear As a eonsequenee the team eoneentrated on stratigraphie problems, and atter 3 weeks the working area was moved southwards to Vibeke Sø (Hudson Land) and Brogetdal (Strindberg Land) (fig. 1) where the rest of the season was spent.
Sedimentological and structural investigations of the Devonian basin, East Greenland
Authors: Larsen P.-H , Olsen H , Rasmussen F.O , Wilken U.G
Published: June 2021

Sedimentological and structural studies of the Middle to Upper Devonian deposits in East Greenland were initiated in 1986 (Marcussen et al., 1987) and continued in 1987 (Marcussen et al., 1988) and in 1988. Field work was carried out from late June to late August, but during a three week period from late July to early August it was hampered by bad weather in the region. The 1988 activities were concentrated around Moskusoksefjord, on Gauss Halvø west of Gastisdal and in Moskusokselandet. Shorter periods were spent in Ole Rømer Land and in northern Hudson Land, with short visits to Ymer Ø and Geographical Society Ø (fig. 1).
The Proterozoic mobile belt in the Ammassalik region, South-East Greenland (Ammassalik mobile belt): an introduction and re-appraisal
Authors: Chadwick B , Dawes P.R , Escher J.C , Friend C.R.L , Hall R.P , Kalsbeek F , Nielsen T.F.D , Nutman A.P , Soper N.J , Vasudev V.N
Published: June 2021

The Ammassalik mobile belt is characterised by a regional layer cake structure of tectonically interleaved sheets of quartzo-feldspathic orthogneisses and supracrustal rocks. The sheets of supracrustal rocks are most abundant in the north of the belt and they include semi-pelitic kyanite-sillimanite gneisses, graphitic schists, marble, amphibolites and local peridotite. The sheets are regarded as parts of a disrupted supracrustal sequence, here termed the Siportoq supracrustal association. Preliminary isotopic age data suggest that most of the orthogneisses are late Archaean, although some have early Proterozoic ages. The Siportoq supracrustal association has yielded an early Proterozoic age. Amphibolite dyke swarms were emplaced at various stages in the evolution of the mobile belt. The Ammassalik belt has an ill-defined northern limit marked by heterogeneous retrogression of a granulite facies terrain up to 100 km wide. Most of the belt is at amphibolite facies, with its southern limit lying to the south of the area considered here. The structure in the south is dominated by nappes and shear zones dipping NE within a wide tract of late Archaean orthogneisses intruded by amphibolite dyke swarms with relatively well preserved primary characteristics. The structure in the north is characterised by more pervasive deformation which gave rise to complex sequences of thrusting and nappe development propagating from the north. Large domes were superimposed on the nappe pile, perhaps as buoyancy phenomena. The dioritic Ammassalik Intrusive Complex (c. 1885 Ma) with its granulite facies assemblages is regarded as a late kinematic phenomenon. Major post-tectonic complexes of granite, diorite and gabbro (c. 1580 Ma) were intruded at a high level well after the close of the tectonism in the Ammassalik mobile belt.
Reconnaissance P,T studies of Proterozoic crustal evolution of the Ammassalik area, East Greenland
Authors: Nutman A.P , Friend C.R.L
Published: June 2021

The Ammassalik area of East Greenland lies in the centre of a 300 km wide early Proterozoic mobile belt, dominated by Archaean gneisses and early Proterozoic metasediments. Regional Proterozoic synkinematic metamorphism was associated with crustal thickening by southerly-directed thrusting and isoclinal folding. Maximum P, T conditions recorded during the regional metamorphism are found in the northern half of the mobile belt and are 9.5 kbar (equivalent to 30 km burial) and c. 700°C. Following some erosion and uplift, the late kinematic 1885 Ma Ammassalik Intrusive Complex (AIC) was intruded at pressures of c. 7 kbar (equivalent to a depth of 20 km). Temperatures in the metamorphic aureole of the AIC reached 800°C. Following further erosion and uplift, post kinematic, c. 1575 Ma granite-diorite-gabbro complexes were intruded, under pressures of 2.5 kbar (equivalent to a depth of 8 km).
The Ivnartivaq complex, Sermilik, Ammassalik
Authors: Brooks C.K , Stenstrop G
Published: June 2021

The Ivnartivaq complex is a small ultramafic body enclosed in quartzo-feldspathic gneisses. It consists largely of serpentinite but has a core of fresh dunite and abundant veins of asbestiform minerals containing amphibole, talc, chlorite and magnetite. The complex is early Proterozoic in age. It probably does not contain economic deposits of either industrial or metallic minerals.
The Sulugssut intrusive complex: a new Tertiary alkaline centre in East Greenland
Authors: Brooks C.K , Dawes P.R , Soper N.J
Published: June 2021

The Sulugssut intrusive complex, discovered in 1986, lies between the glaciers of K. J. V. Steenstrup Søndre Bræ and K. J. V. Steenstrup Nordre Bræ at 66° 30´N. It has an approximate diameter of 5 km and consists of dense dyke swarms and a plutonic core in which tinguaites and ijolites appear to predominate. It is of particular interest on three main counts: (1) it represents the most southerly in the line of Tertiary igneous centres which stretches over 1000 km to the north, (2) its petrographic character, although resembling the Gardiner intrusion to the north, is unique in East Greenland, and (3) it is located dose to the coast confounding earlier ideas that highly undersaturated magmas occur only inland.
Trace fossils from the Lower Cambrian Bastion Formation of North-East Greenland
Authors: Pickerill R.K , Peel J.S
Published: June 2021

New trace fossil collections are described from Lower Cambrian siliciclastic shallow marine shelf deposits of the Bastion Formation of North-East Greenland, together with a taxonomic re-assessment of previously reported material. The entire assemblage comprises 19 ichnogenera, 25 ichnospecies, as well as two vernacular ichnotaxa. Although no new ichnotaxa are present the material reveals new information on the 3-dimensional structure of two of the contained ichnogenera, namely Plagiogmus Roedel and Psammichnites TorelI. The stratigraphic range of a single ichnospecies, Rusophycus latus Webby, is formally extended from the Lower Ordovician to the Lower Cambrian. The assemblage compares favourably with Lower Cambrian ichnocoenoses described from other continents, particularly at the ichnogeneric level. Comparison with similar sequences suggests that the sub-trilobitic Lower Bastion Formation is late Tommotian to early Atdabanian in age, possibly entirely Atdabanian.
Thermal maturity history of the Upper Permian succession in the Wegener Halvø area, East Greenland
Authors: Christiansen F.G , Piasecki S , Stemmerik L
Published: June 2021

The Upper Permian succession, which is considered the most interesting exploration target in Jameson Land, is thermally postmature in the Wegener Halvø area, in contrast to the exposed immature sediments along the western margin of the Jameson Land basin and further north between Traill Ø and Wollaston Forland. Ranking based on Tmax, Hydrogen Index, Ro, Ge and IR data points to a rather constant thermal maturity throughout most of Wegener Halvø (in the upper wet gas zone) with lower maturity towards the south-west in Devondal (in the lower oil zone). The relatively uniform maturity pattern, combined with known thickness of overlying sediments, suggests that regionally increased heat flow in the Tertiary related to the break-up of the North Atlantic, controls the maturity.
The crystalline rocks of western and southern Dove Bugt, North-East Greenland
Authors: Chadwick B , Friend C.R.L , Higgins A.K
Published: June 2021

The land areas around Dove Bugt are dominated by quartzo-feldspathic orthogneisses with a complex history of emplacement and deformation. The oldest rocks recognised are supracrustal units, mainly marbles and rusty-weathering metasedimentary rocks. Locally gabbro-anorthosite units are associated with the supracrustal rocks. These rock units are cut by different phases of the gneisses, of which the most abundant are grey banded orthogneisses. Two different varieties of pink orthogneiss are also recognised. Different types of tabular amphibolitic bodies, relicts of dykes or sills, cut most rock types. The area lies within the East Greenland Caledonian fold belt, but available isotopic data suggest that the crystalline rocks include Archaean and early Proterozoic suites which have undergone uncertain degrees of Caledonian reworking. It is not clear at present how much of the deformation history of at least four periods of deformation and associated mylonitisation is Caledonian, and how much pre-Caledonian.
Economic mineral resources: activities in 1990
Authors: Schønwandt H.K
Published: June 2021

The most exciting discovery in mineral exploration in Greenland in 1990 was announced by Platinova Resources Ltd. and Corona Corporation. A single packsack drill hole intersected a gold-platinum rich zone in the layered mafic Kap Edvard Holm complex of East Greenland (Fig. 1). The mineralised zone consists of an upper gold-rich section overlying a platinum-rich section. Gold values averaged 2.6 ppm over 1.5 m while the bottom section of the hole yielded 3.4 ppm platinum. Surface sampling indicates that the platinum mineralisation extends 1.5 to 2 m below the bottom of the drill hole. The mineralised zone occurs in a well-defined layered sequence which can be followed for more than 10 km.
Regional Caledonian structure of Hertugen af Orléans Land, North-East Greenland
Authors: Strachan R.A , Jepsen H.F , Kalsbeek F
Published: June 2021

Three structural elements of the East Greenland Caledonides are present in Hertugen af Orleans Land: (1) a marginal NNE-SSW trending zone of crystalIine basement rocks overlain by middle Proterozoic sediments (Trekant Series) in the westernmost nunatak area, characterised by folds and thrusts; (2) a central NNE–SSW trending belt of alIochthonous orthogneisses dominated by upright and west-vergent folds; and (3) and eastern N–S trending sinistral shear zone of intensely sheared, mylonitic gneisses (Storstrømmen shear zone). This structural pattern is a continuation of the structural elements in Dronning Louise Land, 40 km to the south-south-east. The late Caledonian Storstrømmen shear zone and its northward continuation define a 10 km wide linear feature of regional significance which can be followed along strike for more than 300 km.
The high-grade gneisses in the south-west of Dove Bugt: an old gneiss complex in a deep part of the Caledonides of North-East Greenland
Authors: Chadwick B , Friend C.R.L
Published: June 2021

The complex range of orthogneisses has been subdivided on the basis of field characteristics into an old polyphase group, grey phlebitic gneisses, younger varieties of pink granitic gneisses that occur principally as extensive sheets, mixed orthogneisses with schlieric facies and undifferentiated gneisses with dioritic facies. Mafic sheets, now amphibolites, were emplaced at various stages in the evolution of the gneisses. Enclaves and sheets of supracrustal rocks include paragneisses, graphitic schists, marble, amphibolite and stratiform gabbroic complexes with anorthosite. Nappes with curvilinear hinge lines and belts of mylonite developed in high amphibolite conditions after emplacement of the sheets of pink granitic rocks (now variably deformed gneisses) into the old orthogneisses and supracrustal rocks. Principal displacements in the mylonites were shallow and N-directed. The nappes and mylonites were deformed by upright-inclined folds with north-westerly vergence. The nappes, mylonites and north-westerly verging folds are presumed to be Caledonian. N- and S-directed extensions indicated by small-scale ductile structures younger than the regional folding suggest that longitudinal collapse predominated in this part of the Caledonian belt in the south-west of Dove Bugt.
A problematical trilobite from the Lower Cambrian of Freuchen Land, central North Greenland
Authors: Lane P.D , Rushton A.W.A
Published: June 2021

A single specimen of a remarkable trilobite is described from the Early Cambrian Buen Formation of north-east Freuchen Land, central North Greenland. It is referred with doubt to Alacephalus Repina, 1960, as a new species A? davisi sp. nov. It possibly lacked eyes, which makes it one of, if not the, earliest non-agnostoid trilobite with this adaptation. Its thoracic segments have a unique morphology. In some respects the morphology resembles that of various trilobites adapted to low-energy benthic environments of low oxygenation; such trilobites tend to be widely distributed, and in agreement with this Alacephalus appears to be interprovincial.
Palynostratigraphy of the Lower Tertiary volcanics and marine clastic sediments in the southern part of the West Greenland Basin: implications for the timing and duration of the volcanism
Authors: Piasecki S , Larsen L.M , Pedersen A.K , Pedersen G.K
Published: June 2021

Volcanic rocks, forming hyaloclastites and subaqueous lava flows, were deposited intercalated with clastic sediments in a water-filled basin in West Greenland in the Early Tertiary. Three main stages of basin infilling occurred in the Disko-Nuussuaq area. The distribution of dinoflagellate cysts in the sediments shows that the basin was marine in the first stage and non-marine in the second stage of infilling. In the third stage the basin was displaced towards the south and was marginally marine. The dinoflagellate cysts form a typical mid-Paleocene assemblage which may be correlated with the calcareous nannoplankton (NP) zonation. The stratigraphically lowest investigated localities are coeval with the uppermost part of nannoplankton zone NP4, whereas the overlying localities within the marine basin (first stage) may be correlated with NP5-6. The localities from the non-marine second stage cannot be correlated with the NP zonation because they do not contain dinoflagellate cysts. Localities from the third stage are coeval with NP7-8. Younger volcanics are subaerially deposited. The total known range of the volcanics now falls within the NP3 to NP8 interval, giving a minimum duration for the main plateau-building stage of the volcanism of 4–6 million years. The subaerial basalts have previously been found to be mainly reversely magnetised, with one normally magnetised sequence which can now be stratigraphically correlated with NP4, and thereby identified as anomaly 27. The basalts in East Greenland started erupting during the NP9 zone, so that the volcanic activity in East Greenland largely succeeded that in West Greenland. In relation to the postulated mantle plume in the North Atlantic this means that the volcanic activity started in the peripheral part of the plume and only later switched to the central part.
Geologic photogrammetry using standard small-frame cameras
Authors: Dueholm K.S
Published: June 2021

Multi-model photogrammetry enables precise three-dimensional measurements from strips or blocks of overlapping small-frame photographs (colour slides). The method can be used for geo-scientific terrain analysis and mapping. Of special interest is the ability to map otherwise inaccessible terrain features such as geological outcrops on steep mountain faces and canyon walls. Field photography is carried out without special photogrammetric training using ordinary small-frame cameras. Photographs can be taken at any scale and angle from terrestrial stations, helicopters, light planes, or boats. In the laboratory, strips or blocks of small-frame photographs are set up in an analytical stereo-plotter where multiple stereoscopic model pairs are simultaneously orientated. Interpretation and compilation is continuous across model boundaries. Data can be plotted in many different projections. The multi-model photogrammetric technique is explained and procedures are outlined for camera calibration, photography, and acquisition of ground-control information.
New methods for the geological analysis of Tertiary volcanic formations on Nuussuaq and Disko, central West Greenland, using multi-model photogrammetry
Authors: Pedersen A.K , Dueholm K.S
Published: June 2021

A series of experiments with multi-model photogrammetry were made during the compilation of a 80 km long section along the south coast of Nuussuaq. The section covers a range of Tertiary volcanic lithologies which overlie Mesozoic to Tertiary clastic sediments. The multi-model method allows the geological analyses of flat-lying lithologies in steep or inaccessible terrain and the compilation of detailed sections, profiles, and block diagrams. Drawing of sections or maps is combined with accurate structural measurements to document the flow directions of both subaerial and subaqueous volcanic units and to demonstrate syn-and post-volcanic basin movements and the location of volcanic eruption sites. Multi-model photogrammetry experiments made by compiling the geology of areas already covered by field work has led to major new discoveries. Similar experiments made on areas, which had not been visited in the field before the compilation, but which were visited later, demonstrates that the method is an important new tool in geological reconnaissance.
Disko Bugt Project 1992, West Greenland
Authors: Christiansen F.G
Published: June 2021

One of GGU's major field activities in 1992 took place in July and August in the Disko-Nuussuaq-Svartenhuk Halvø area of central West Greenland. This was the fourth and final year of field studies under the 'Disko Bugt Project', carried out from 1988–1992 with one summer's break in 1990. The Disko Bugt Project includes a large number of activities, essentially within two very different geological provinces: the Archaean-Proterozoic basement and supracrustal province, and the onshore part of the Cretaceous–Tertiary sedimentary and volcanic basin. The Precambrian basement is mainly exposed towards the east, and the sediments and volcanic rocks mainly towards the west.
Use of Rb-Sr isotope data to constrain the time of deposition of Precambrian metasediments: an example from Hamborgerland, West Greenland
Authors: Kalsbeek F
Published: June 2021

In high-grade metamorphic terrains it is often not possible to determine the relative age of metasedimentary units by field investigation. However, the time of deposition of the original sediment can be constrained by consideration of the Sr-isotopic evolution of the rocks on the scale of an outcrop. An outline of the method is given, and Rb-Sr data for high-grade (granulite facies) metasediments from HamborgerIand, West Greenland, are discussed as an example. Sm-Nd model age data indicate that these rocks were derived by erosion of a 3000–3200 Ma basement. Deposition took place not long before 2700 Ma ago, and closure of the Rb-Sr isotope system after high-grade metamorphism occurred at about 2600 Ma.
ODP activities on the South-East Greenland margin: Leg 152 drilling and continued site surveying
Authors: Larsen H.C , Saunders A , Larsen L.M , Lykke-Andersen H , ODP Leg 152 shipboard party  , Marcussen C , Clausen L
Published: June 2021

Two main types of passive margins known as volcanic and non-volcanic rifted margins, based on the extent of volcanic activity associated with their formation, are widely recognised. Volcanic rifted margins have now been identified along the edges of many continents (Coffin & Eldholm, 1992) and cannot any longer be considered as rare exceptions to 'normal' (non-volcanic) continental break-up.
Upper Palaeozoic fusulinid assemblages, Wandel Sea Basin, North Greenland
Authors: Nilsson I
Published: June 2021

Eight fusulinid assemblages are recognized in the Mallemuk Mountain Group of North Greenland. They are of late Moscovian (Wedekindellina assemblage), late Kasimovian (Rauserites ex. gr. simplex assemblage), early-middle Gzhelian (Rauserites ex. gro rossicus assemblage), late Gzhelian – ?early Asselian (Schellwienia arctica assemblage), early Asselian (Sphaeroschwagerina aff. S. vulgaris assemblage), middle-late Asselian (Schwagerina ex. gro nathorsti assemblage), latest Asselian - earliest Sakmarian (Schwagerina aff. S. moelleri – S. ex. gro exuberate assemblage) and late Sakmarian (Schwagerina plicatissima assemblage) ages. These assemblages show close similarities to faunas described elsewhere in the present Arctic region, i.e. Arctic Russia, Southwest Barents shelf, Svalbard and Arctic Canada.
Organic geochemistry of the Lower Jurassic Sortehat Formation, Jameson Land, East Greenland
Authors: Krabbe H , Christiansen F.G , Dam G , Piasecki S , Stemmerik L
Published: June 2021

Biomarker analyses of Lower Jurassic shales from the Sortehat Formation, Jameson Land, central East Greenland carried out in combination with palynological studies demonstrate deposition in a fresh to brackish water environment, which became increasingly saline towards the top. The formation is regionally immature to early mature with respect to hydrocarbon generation, and the lowermost 2–20 m have a fair generation potential. Biomarker analysis of the brackish water part shows dominance of C16–C21 n-alkanes, high pristane/phytane ratios, high hopane/sterane ratios, high relative amounts of C29–C31 hopanes and C2717α-trisnorhopane. Steranes are dominated by C29 isomers. The organic matter is composed of bacteria, algae and land plants interpreted from biomarker distributions. The combined data set suggests that deposition took place during an overall rise in relative sea level.
Geology and petroleum prospectivity of the region offshore southern West Greenland – a summary
Authors: Chalmers J.A , Dahl-Jensen T , Bate K.J , Whittaker R.C
Published: June 2021

Since 1987, the Geological Survey of Greenland (GGU) has been engaged in a re-assessment of the geology and petroleum potential of the region offshore southern West Greenland. In I994, a milestone was reached in this study when, for the first time, a fairly complete understanding of the regional structure and stratigraphy of all of the sedimentary basins and the continental margin off shore southern West Greenland was achieved. This paper presents an account of how the work was carried out and gives a summary of the geological results. Due to the area being offshore, its investigation required the interpretation of geophysical data, primarily seismic data, tied to boreholes.
Geophysical and petroleum geological activities in the Nuussuaq – Svartenhuk Halvø area 1994: promising results for an onshore exploration potential
Authors: Christiansen F.G , Marcussen C , Chalmers J.A
Published: June 2021

After the successful completion of the 1993 field work and drilling programme in the Marraat area on western Nuussuaq (Fig. 1), including a subsequent logging and geophysical programme (see Christiansen et al., 1994a, b; Dam & Christiansen, 1994), a new picture of onshore ex­ploration opportunities has started to develop. Previously the onshore basins were only considered to have a minor exploration potential, if any at all. However, the Disko-Nuussuaq-Svartenhuk Halvo region has been an important study area because many of the key parameters (sedimentological, stratigraphical and organic geochemical data from the excellent outcrops) may be obtained for predicting the distribution of reservoir and source rocks in the neighbouring major offshore basins in North-West and West Greenland (Christiansen et al., 1992, I994c).
Wandel Sea Basin: basin analysis – a summary
Authors: Håkansson E , Stemmerik L
Published: June 2021

In 1991 a three year research project was initiated by the Geological Institute, University of Copenhagen with financial support from the Ministry of Energy, the Danish Natural Science Research Council and the Carlsberg Foundation. The 'Wandel Sea Basin: basin analysis' project was carried out in collaboration with the Geological Survey of Greenland and included field work in North Greenland; in eastern Peary Land in 1991 and Amdrup Land in 1993 (Fig. 1; Hakansson et al., 1994). The project is a continuation of earlier investigations in the Wandel Sea Basin carried out during geological mapping of North Greenland by the Geological Survey of Greenland in 1978–1980 and during later expeditions to the area (e.g. Hakansson, 1979; Hakansson et al., 1981, 1989, 1991, 1994). Hydrocarbon related studies of the Wandel Sea Basin were continued during the 1994 field season (Stemmerik et al., this report).
Project SUPRASYD 1994 - Ketilidian supracrustal rocks in South-East Greenland and gold- bearing shear zones in the Julianehåb batholith
Authors: Garde A.A , Schønwandt H.K
Published: June 2021

The SUPRASYD project is a reassessment of the geo­tectonic setting and mineral potential of the Lower Proterozoic Ketilidian orogenic belt in southern Greenland (previously described by Allaart, 1976 and Kalsbeek et al., 1990), and in particular its supracrustal rocks. During the first field season in 1992 a geological and geochemical reconnaissance programme was carried out in South-East Greenland between approximately latitudes 60° to 62° N, mainly in areas with supracrustal rocks (Steenfelt et al., 1992; Nielsen et al., 1993; Chadwick et al., 1994a). The second season in 1993 focused on the southern part of the Julianehab batholith on the west coast of South Greenland, as well as on shear zones with spatially associated gold mineralisation (Garde & Schonwandt, 1994; Chadwick et al., 1994b; Stendal et al., in press). Field work from the early 1960s was re-evaluated and supplemented with new mapping with the aim of compilation of the 1: 100 000 scale map sheet 60 V.3, Sondre Sermilik.
The Danish Lithosphere Centre: a new earth science centre in Denmark
Authors: Larsen H.C
Published: June 2021

The Danish Lithosphere Centre (DLC) is funded by the Danish National Research Foundation (DNRF) and was formed on 1 February, 1994 following a two year long planning and application phase. A total sum of 70 million Danish kroner has been granted to DLC over five years in order to carry out the research plan included in the original proposal. Extensive field programmes were initiated in 1994, and by end 1994 the centre was almost fully staffed. The general aim and format of the overall research plan of the centre are summarised below. The preliminary results of the 1994 work programmes are given by Marker et al. (this report) and Larsen et al. (this report).
The Tertiary opening of the North Atlantic: DLC investigations along the east coast of Greenland
Authors: Larsen H.C , Brooks C.K , Hopper J.R , Dahl-Jensen T , Pedersen A.K , Nielsen T.F.D , Field parties
Published: June 2021

Work along the east coast of Greenland in the summer of 1994 represents the initiation of the Danish Lithosphere Centre (DLC) investigations into the magmatic and tectonic evolution accompanying initial break-up of the North Atlantic in this area. As described by Larsen (this report), the aims of DLC are the understanding of the composition and thermal state of the asthenosphere and the deformation of the lithosphere during continental break-up and formation of volcanic rifted margins. Furthermore, the time scale of these events is crucial to any model of break-up.