scholarly journals Stratabound copper-lead-zinc mineralisation in the Permo-Triassic of central East Greenland

1982 ◽  
Vol 143 ◽  
pp. 1-42
Author(s):  
B Thomassen ◽  
L.B Clemmensen ◽  
H.K Schønwandt
Keyword(s):  
Middle Triassic ◽  
Lower Triassic ◽  
Upper Triassic ◽  
Alluvial Fan ◽  
Upper Permian ◽  
Geochemical Data ◽  
East Greenland ◽  
Lead Zinc ◽  
Copper Lead ◽  
Carbonate Buildup

Stratabound and stratiform copper-lead-zinc-mineralised horizons confined to specific sedimentary fades in the Permo-Triassic Jameson Land Basin of East Greenland were revealed during recent exploration and sedimentological studies. The occurrences are divided into fault-bounded-stratabound and stratabound-stratiform mineralisation. The first group comprises lead-zinc-copper mineralisation in Upper Permian limestone; the remaining mineralisation falls in the second group which is subdivided into mineralisation hosted in mudstones, in sandstones with mudflasers and in sandstones and conglomerates. A lithogeochemical programme helped to define the mineralised horizons in the Triassic. During the interpretation of the geochemical data an empiric statistical function was introduced which is an estimate of how anomalous the 95 per cent fractile is for individual elements compared with the frequency distribution around the median. The Upper Permian sediments host copper in basal shoreline conglomerates, zinc-lead-copper in lagoonal mudstones and lead-zinc-copper in carbonate buildup and shelf fades. The Lower Triassic contains copper-lead mineralisation in alluvial fan sediments, the Middle Triassic hosts lead-zinc-copper in sandy shoreline limestones and lagoonal mudstones and copper-lead-zinc in gypsiferous lacustrine sandstones and mudstones while the Upper Triassic contains copper in both dolomitic lacustrine sandstones and mudstones and in overlying carbonate-rich fluvial channel sandstones.

scholarly journals New biostratigraphic evidence of Late Permian to Late Triassic deposits from Central Tibet and their paleogeographic implications

Lithosphere ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 683-696 ◽  
Author(s):  
Gui-chun Wu ◽  
Zhan-sheng Ji ◽  
Wei-hua Liao ◽  
Jian-xin Yao
Keyword(s):  
Middle Triassic ◽  
Carbonate Platform ◽  
Lower Triassic ◽  
Upper Triassic ◽  
Suture Zone ◽  
Late Triassic ◽  
Upper Permian ◽  
Early Triassic ◽  
Late Permian ◽  
The North

Abstract Triassic deposits in the Bangong-Nujiang Suture Zone are important for understanding its tectonic nature and evolutionary history, but have not been systematically studied due to a lack of biostratigraphic data. For a long time, the Upper Triassic Quehala Group featuring clasolite has been regarded as the only rocky unit. In recent years, the silicite-dominated Gajia Formation that bears radiolarian fossils was suggested to represent Ladinian to Carnian deposits. The Upper Permian and Lower Triassic rocks have never been excavated and thus are considered to be absent. This research, however, reveals that fossils aged from the Late Permian to Anisian of the Middle Triassic and Norian of the Late Triassic have been preserved in the central Bangong-Nujiang Suture Zone, which provides evidence of Upper Permian to early Middle Triassic deposits and provides new insights on the Upper Triassic strata as well. A new Triassic strata succession is thus proposed for the Bangong-Nujiang Suture Zone, and it demonstrates great similarities with those from Lhasa to the south and Qiangtang to the north. Therefore, we deduce that the Bangong-Nujiang Suture Zone was under a similar depositional setting as its two adjacent terranes, and it was likely a carbonate platform background because limestones were predominant across the Triassic. The newly acquired biostratigraphic data indicate that Lhasa and Qiangtang could not have been located on two separate continents with disparate sedimentary settings; therefore, the Bangong-Nujiang Suture Zone likely did not represent a large ocean between them. This conclusion is supported by lithostratigraphic and paleomagnetic research, which revealed that Lhasa and Qiangtang were positioned at low to middle latitudes during the Early Triassic. Combining this conclusion with fossil evidence, we suggest that the three main Tibetan terranes were in the same palaeobiogeographic division with South China, at least during the Latest Permian to Early Triassic. The Early Triassic conodont species Pachycladina obliqua is probably a fossil sign of middle to low latitudes in palaeogeography.

Helmolepis cyphognathus, sp. nov., a new platysiagid actinopterygian from the Lower Triassic Sulphur Mountain Formation (British Columbia, Canada)

2005 ◽  
Vol 42 (1) ◽  
pp. 25-36 ◽  
Author(s):  
Andrew G Neuman ◽  
Raoul J Mutter
Keyword(s):  
British Columbia ◽  
New Species ◽  
Central Europe ◽  
Middle Triassic ◽  
Lower Triassic ◽  
Western Canada ◽  
Early Triassic ◽  
East Greenland ◽  
The Family ◽  
A New Species

A new species of stem actinopterygian, Helmolepis cyphognatus sp. nov., is reported from the Lower Triassic Sulphur Mountain Formation of western Canada (probably Smithian). This taxon differs from the only other known Early Triassic platysiagid, H. gracilis from the Lower Triassic Wordie Creek Formation of East Greenland (Griesbachian), in counts of branchiostegal rays, shape of the maxilla, shape (and possibly counts) of extrascapulars, and the size ratio of major opercular bones. In spite of their overall unfavorable preservation, the numerous available specimens amend our knowledge of the little known genus Helmolepis considerably: it has become evident that the morphology of Helmolepis cyphognatus sp. nov. comes closest to Platysiagum minus (Middle Triassic Besano Formation of central Europe). This study suggests placement of the two genera in the family Platysiagidae. Investigation of this new species also shows certain features of the cheek and the caudal fin are more primitive than previously believed, whereas the snout region is probably derived but of yet uncertain affinities in Helmolepis.

scholarly journals A reappraisal of the Middle Triassic chirotheriid Chirotherium ibericus Navás, 1906 (Iberian Range NE Spain), with comments on the Triassic tetrapod track biochronology of the Iberian Peninsula

2015 ◽  
Author(s):  
Ignacio Díaz-Martínez ◽  
Diego Castanera ◽  
José Manuel J.M. Gasca ◽  
José Ignacio Canudo
Keyword(s):  
Iberian Peninsula ◽  
Middle Triassic ◽  
Lower Triassic ◽  
Upper Triassic ◽  
Worldwide Distribution ◽  
Track Record ◽  
Iberian Range ◽  
Vertebrate Tracks ◽  
The 19Th Century ◽  
Stratigraphic Range

Triassic vertebrate tracks are known from the beginning of the 19th century and have a worldwide distribution. Several Triassic track ichnoassemblages and ichnotaxa have a restricted stratigraphic range and are useful in biochronology and biostratigraphy. The record of Triassic tracks in the Iberian Peninsula has gone almost unnoticed although more than 25 localities have been described since 1897. In one of these localities, the naturalist Longinos Navás described the ichnotaxon Chirotherium ibericus in 1906.The vertebrate tracks are in two sandy slabs from the Anisian (Middle Triassic) of the Moncayo massif (Zaragoza, Spain). In a recent revision, new, previously undescribed vertebrate tracks have been identified. The tracks considered to be C. ibericus as well as other tracks with the same morphology from both slabs have been classified as Chirotherium barthii. The rest of the tracks have been assigned to Chirotheriidae indet., Rhynchosauroides isp. and undetermined material. This new identification of C. barthii at the Navás site adds new data to the Iberian record of this ichnotaxon, which is characterized by the small size of the tracks when compared with the main occurrences of this ichnotaxon elsewhere. As at the Navás tracksite, the Anisian C. barthii-Rhynchosauroides ichnoassemblage has been found in other coeval localities in Iberia and worldwide. This ichnoassemblage belongs to the upper Olenekian-lower Anisian interval according to previous biochronological proposals. Analysis of the Triassic Iberian record of tetrapod tracks is uneven in terms of abundance over time. From the earliest Triassic to the latest Lower Triassic the record is very scarce, with Rhynchosauroides being the only known ichnotaxon. Rhynchosauroides covers a wide temporal range and gives poor information for biochronology. The record from the uppermost Lower Triassic to the Middle Triassic is abundant. The highest ichnodiversity has been reported for the Anisian with an assemblage composed of Dicynodontipus, Procolophonichnium, Rhynchosauroides, Rotodactylus, Chirotherium, Isochirotherium, Coelurosaurichnus and Paratrisauropus. The Iberian track record from the Anisian is coherent with the global biochronology proposed for Triassic tetrapod tracks. Nevertheless, the scarcity of track occurrences during the late Olenekian and Ladinian prevents analysis of the corresponding biochrons. Finally, although the Iberian record for the Upper Triassic is not abundant, the presence of Eubrontes, Anchisauripus and probably Brachychirotherium is coherent with the global track biochronology as well. Thus, the Triassic track record in the Iberian Peninsula matches the expected record for this age on the basis of a global biochronological approach, supporting the idea that vertebrate Triassic tracks are a useful tool in biochronology.

New Triassic dicynodonts from South America, their origins and relationships

1965 ◽  
Vol 248 (753) ◽  
pp. 457-514 ◽  
Keyword(s):  
New Genus ◽  
Middle Triassic ◽  
Taxonomic Status ◽  
Lower Triassic ◽  
Upper Permian ◽  
South American ◽  
Black Rhinoceros ◽  
The Family ◽  
White Rhinoceros ◽  
African Genus

Richly fossiliferous deposits have been found in the Ischigualasto region of Argentina in the last few years. The only known dicynodont from this area is the new genus Ischigualastia , of which a diagnosis and fully illustrated description are given. A specimen from Brazil, which had earlier been referred to the genus Stahleckeria as S. lenzii , is shown to be very similar to Ischigualastia , but not generically identical with it; this specimen is therefore placed in the new genus Barysoma . The only South American dicynodont which had previously been fully described is Stahleckeria , from Brazil. A diagnosis and fully illustrated description are now given of the complete skeleton of the genus Dinodontosaurus , also from Brazil. Earlier Brazilian material which had been referred to the African genus Dicynodon is shown to belong to Dinodontosaurus . A very large skull from the same deposits is identical with Dinodontosaurus , except that it has a much more massive snout and tusks, and a wider occiput. The dicynodonts are herbivorous, and may well have lived in herds; it is suggested that the massive skull may belong to the old male of such a herd of Dinodontosaurus , and it is therefore not given separate taxonomic status. The skull of Placerias , the only dicynodont known from North America, had previously been restored by Camp & Welles (1956) from the broken remains of about forty individuals. Comparison of the restored skull with that of Ischigualastia has suggested various modifications in the reconstruction, and illustrations of the new reconstruction are given. The relationships of the Triassic dicynodonts are discussed. It is suggested that, excluding the specialized genus Lystrosaurus , they show two main divergent adaptations, which are probably related to their mode of feeding. A pointed snout and high occiput is thought to characterize the family Kannemeyeriidae (which includes the forms Kannemeyeria, ‘Kannemeyeria’ vanhoepeni, Sinokannemeyeria, Parakannemeyeria, Ischigualastia, Barysoma and Placerias ). A blunt snout and wide occiput is thought to characterize the family Stahleckeriidae (which includes the genera Stahleckeria and Dinodontosaurus ). A similar distinction is found today between the browsing black rhinoceros and the grazing white rhinoceros. The most primitive kannemeyeriids are found in the Lower Triassic of China, and these forms may also be ancestral to the stahleckeriids. The only other Triassic dicynodonts, Shansiodon and ‘ Dicynodon’ njalilus , may be placed in a separate family, the Shansiodontidae. All these Triassic genera have two features in common: the presence of a separately ossified olecranon process on the ulna, and a shortened interpterygoid vacuity. It is possible that this may indicate a common ancestry for them all, but no Upper Permian or Basal Triassic genera now known appear to be possible ancestors for them. The lack of any Middle Triassic vertebrate fauna in the northern hemisphere makes it very difficult to date the Argentinian and Brazilian faunas, which include gomphodont cynodonts, dicynodonts, rhynchosaurs, pseudosuchians and a few saurischians. It is not felt that the presence of rhynchosaurs necessarily indicates a Middle Triassic age, as the group is known from the mid-Norian of India. It is possible that the presence of several saurischians and of a pseudosuchian closely related to the German Norian genus Aëtosaurus , may indicate a Carnian age for the Argentine fauna. The Brazilian fauna is somewhat dissimilar to that of Argentina and contains no genera in common with it; it may therefore be of earlier, Ladinian, age. The fauna of the Manda Beds of East Africa is similar in composition to that of Brazil, but contains no genera in common with it. It also lacks saurischians and includes a dicynodont, Kannemeyeria , that is otherwise typical of the Lower Triassic Cynognathus zone of South Africa. It may therefore be Anisian in age.

scholarly journals Initiation of petroleum exploration in Jameson Land, East Greenland

1986 ◽  
Vol 128 ◽  
pp. 103-121
Author(s):  
F Surlyk ◽  
S Piasecki ◽  
F Rolle
Keyword(s):  
Lower Triassic ◽  
Scientific Work ◽  
Upper Jurassic ◽  
Source Rocks ◽  
Petroleum Exploration ◽  
Upper Permian ◽  
Lower Permian ◽  
Western Basin ◽  
East Greenland ◽  
Promising Source

Active petroleum exploration in East Greenland is of fairly recent date and was preceded by a much longer history of scientific work and mineral exploration. The discovery in 1948 of lead-zinc mineralisation at Mestersvig resulted in the formation of Nordisk Mineselskab AIS in 1952. In the beginning of the seventies Nordisk Mineselskab initiated cooperation with the American oil company Atlantic Richfield (ARCO) in order to undertake petroleum exploration in Jameson Land. The Jameson Land basin contains a very thick Upper Palaeozoic - Mesozoic sedimentary sequence. Important potential source rocks are Lower Permian lacustrine mudstone, Upper Permian black marine mudstone, Middle Triassic dark marine limestone, uppermost Triassic black marginal marine mudstone, Lower Jurassic black mudstone and Upper Jurassic deep shelf black mudstone. Tbe Upper Permian mudstone, which is the most promising source rock, is immature to weakly mature along the western basin margin and is expected to be in the oil or gas-generating zone when deeply buried in the central part of the basin. Potential reservoir rocks include Upper Permian bank and mound limestones, uppermost Permian fan delta sandstones, Lower Triassic aeolian and braided river sandstones, and Lower, Middle and Upper Jurassic sandstones. The most important trap types are expected to be stratigraphic, such as Upper Permian limestone bodies, or combination stratigraphic-structural such as uppermost Permian or Lower Triassic sandstones in Early Triassic tilted fault blocks. In the offshore areas additional play types are probably to be found in tilted Jurassic fault blocks containing thick Lower, Middle and Upper Jurassic sandstones and lowermost Cretaceous sandstones and conglomerates. The recognition of the potential of the Upper Permian in petroleum exploration in East Greenland has important implications for petroleum exploration on the Norwegian shelf.

scholarly journals Integrating 3D photogeology with aeromagnetic data as a tool for base-metal exploration in East Greenland

1969 ◽  
Vol 31 ◽  
pp. 71-74
Author(s):  
Anaïs Brethes ◽  
Pierpaolo Guarnieri ◽  
Thorkild M. Rasmussen
Keyword(s):  
Base Metal ◽  
Geophysical Data ◽  
Three Dimensions ◽  
Aeromagnetic Data ◽  
East Greenland ◽  
Stratigraphic Architecture ◽  
Lead Zinc ◽  
Greenland Margin ◽  
Basin System ◽  
Copper Lead

An 800 km long basin system developed along the East Greenland margin since the Late Palaeozoic in which the Jameson Land Basin forms the southern part of the system. Along the margins of the Jameson Land Basin there are occurrences of barite, copper, lead, zinc and silver, which are particularly abundant in the northern part of the basin’s eastern margin in the Wegener Halvø area (Fig. 1). Structures and stratigraphic architecture play important roles in the mineralisation distribution, so detailed mapping is essential. We used 3D photogeology combined with geophysical data to map the different stratigraphic units, faults and dykes in three dimensions.

scholarly journals Erosional unconformity at the base of marine Lower Triassic at Wegener Halvø, central East Greenland

1977 ◽  
Vol 85 ◽  
pp. 103-107
Author(s):  
K Birkenmajer
Keyword(s):  
Lower Triassic ◽  
Upper Permian ◽  
Sharp Change ◽  
Triassic Boundary ◽  
East Greenland ◽  
A Minor ◽  
Permian Triassic Boundary

The Permian-Triassic boundary in East Greenland has been studied mainly in the areas of Kap Stosch (Nielsen, 1935; Teichert & Kummel, 1973) and Wegener Halvø (Triimpy, 1961; Grasmiick & Triimpy, 1%9), and to alesser extent in western Scoresby Land (AelIen, in Triimpy, 1%1; Perch-Nielsen et al., 1972, 1974). According to Nielsen (1935) the boundary is not recognisable in the westernmost exposures at Kap Stosch where the lowermost Triassic Glyptophiceras triviale Zone was found. Further to the east the boundary is marked by a sharp change in facies from limy or shaly (Upper Permian) to sandy (Lower Triassic) deposits, the G. triviale Zone is missing, and locally a minor conglomerate appears at the base of the Triassic.

scholarly journals Preliminary palynostratigraphy of the Permiart -Lower Triassic sediments in Jameson Land and Scoresby Land, East Greenland

1984 ◽  
Vol 32 ◽  
pp. 139-144
Author(s):  
Stefan Piasecki
Keyword(s):  
Preliminary Investigation ◽  
Lower Triassic ◽  
Upper Permian ◽  
Lower Permian ◽  
Gradual Change ◽  
East Greenland ◽  
Fine Grained ◽  
Lowermost Part

The presumed Carboniferous, Permian and Lower Triassic sediments of Jameson Land and Scoresby Land, have been palynologically investigated. Four main assemblages are recognised which form the basis for a coarse stratigraphy. The Lower Permian Potonieisporites assemblage occurs in all palynologically productive fine-grained sediments from the Gurreholm Dai and the Mesters Vig Formations. The lowermost part of these sediments in Skeldal may be of latest Carboniferous age. An Upper Permian Vittatina assemblage characterises the lower part of the Foldvik Creek Formation. An Upper Permian / Lower Triassic Protohaploxypinus assemblage occurs in the upper part of the Foldvik Creek Formation. The Lower Triassic Wordie Creek Formation contains a Taeniaesporites assemblage. The preliminary investigation suggests a gradual change in the palynoflora. This again points to presence of a complete or almost complete sedimentary transitional sequence from the Upper Permian to the Lower Triassic.

Petroleum geological activities in East Greenland in 1997

1998 ◽  
pp. 35-42 ◽  
Author(s):  
Michael Larsen ◽  
Stefan Piasecki ◽  
Thomas Preuss ◽  
Lars Seidler ◽  
Lars Stemmerik ◽  
...  
Keyword(s):  
Financial Support ◽  
Sedimentary Basins ◽  
Lower Triassic ◽  
Upper Permian ◽  
East Greenland ◽  
Doctoral Research ◽  
Petroleum Systems ◽  
Geographical Society ◽  
Form Part ◽  
Research Councils

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Larsen, M., Piasecki, S., Preuss, T., Seidler, L., Stemmerik, L., Therkelsen, J., & Vosgerau, H. (1998). Petroleum geological activities in East Greenland in 1997. Geology of Greenland Survey Bulletin, 180, 35-42. https://doi.org/10.34194/ggub.v180.5084 _______________ In 1997, petroleum geological activities were continued in East Greenland in order to increase existing knowledge on the sedimentology and biostratigraphy of the Upper Permian – Mesozoic succession, and to better define and describe the petroleum systems of the basin. The activities form part of the multidisciplinary research project ‘Resources of the sedimentary basins of North and East Greenland’ initiated in 1995 with financial support from the Danish Research Councils, and were mostly continuations of pre- and post-doctoral research (Stemmerik et al. 1996, 1997). Some new activities were initiated during the 1997 season with financial support from Saga Petroleum a.s.a., Norway; they included an evaluation of the thermal effects and diagenetic changes resulting from Paleogene intrusions and a more detailed sedimentological study of the newly identified Jurassic succession of northern Hold with Hope (Stemmerik et al. 1997). Five teams worked in the region in July and August 1997 studying the Upper Permian – Lower Triassic of Wegener Halvø, northern Scoresby Land and Traill Ø, the Middle Jurassic – Lower Cretaceous of Hold with Hope and the Cretaceous of Traill Ø and Geographical Society Ø (Fig. 1). The work was logistically integrated with the Survey’s other mapping activities in the region (see Henriksen 1998, this volume).

Isotopic Dating and Geological Significance of Stratiform Orebody in Gejiu Tin Deposit, Yunnan, China

2012 ◽  
Vol 616-618 ◽  
pp. 43-47
Author(s):  
Ying Shu Li ◽  
Yan Cai ◽  
Jiao Jiao Chen ◽  
Nan Chen ◽  
Lun Wang ◽  
...  
Keyword(s):  
Rare Earth ◽  
Carbonate Rocks ◽  
Middle Triassic ◽  
Copper Deposit ◽  
Ore Deposit ◽  
The World ◽  
Lead Zinc ◽  
Tin Deposit ◽  
Basalt Type ◽  
Copper Lead

Gejiu tin ore deposit is a famous tin-polymetallic deposit in the world because of its enormous metal reserves. Besides tin, there are copper, lead, zinc, silver, iron, sulphur, tungsten, bismuth, indium and rare earth elements. It was believed that there mainly are skarn-type tin deposit, stratiform tin deposit and basalt-type copper deposit in Gejiu tin orefield. The stratiform tin deposit are distributed in Lutangba, Malage and Huangmaoshan, which are hosted by carbonate rocks of Gejiu formation in Middle Triassic Series. 40Ar-39Ar dating of cassiterite from the sratiform tin deposit in Lutangba yields plateau age of 202.18±2.35Ma and isochron age of 206.81±3.23 Ma respectively. The ages are obviously older than those of the ore of the skarn type deposit of the Yanshanian epoch．The mineralization is the seabed exhalative hydrothermal sedimentary mineralization of the Indosinia epoch.

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