Carbonate–sulphate–redbed facies and cyclic sedimentation of the Windsorian Stage (Middle Carboniferous), Maritime Provinces

1969 ◽  
Vol 6 (5) ◽  
pp. 1037-1066 ◽  
Author(s):  
Paul E. Schenk
Keyword(s):  
Calcium Sulfate ◽  
Field Work ◽  
Insoluble Residue ◽  
Maritime Provinces ◽  
Cyclic Sedimentation ◽  
The North ◽  
Salt Flats ◽  
Middle Carboniferous ◽  
Lagoonal Water ◽  
Fundy Basin

After the late Devonian orogeny, thick Carboniferous, mainly continental redbeds, derived from intrabasinal horsts, accumulated in a complex rift-valley system called the Fundy basin. During the mid-Carboniferous Windsorian Stage, generally hypersaline seas flooded repeatedly into the tortuously interconnected, intrabasinal grabens. The resulting carbonate–sulfate blankets intertongue laterally with increasingly coarser redbeds and even basalt adjacent to the horst. Macrofaunal, microfaunal, insoluble residue, heavy-mineral, and trace-element analyses and Irwin-logs have limited success in identifying remnants of each particular blanket. Nevertheless, a Windsorian facies model is constructed from detail microscopy and Recent analogues, including field work in Bermuda.Windsorian carbonates are mainly shallow marine to supratidal; calcium sulfate is mainly diagenetic and supratidal, precipitated within, not on, subaerial salt flats; and redbeds are mainly subaerial and diagenetic, pigmented by post-depositional alteration of iron-rich detrital minerals. Dolomitization was both penecontemporaneous within the salt flat by influxing lagoonal water, and also secondary within buried, permeable, basinward lithosomes by refluxing brine. Gypsum–anhydrite nodules metamorphose on stress from mosaic, through penemosaic structures, and finally to massive, porphyroblastic plutons.Floodings in the Antigonish–Mabou basin were from the north–the present Gulf of St. Lawrence. Cyclic sedimentation was probably due to fluctuating supply of terrigenous detritus into a continually subsiding basin.

Ketilidian structure and the rapakivi suite between Lindenow Fjord and Kap Farvel, South-East Greenland

2000 ◽  
pp. 50-59
Author(s):  
Brian Chadwick ◽  
Adam A. Garde ◽  
John Grocott ◽  
Ken J.W. McCaffrey ◽  
Mike A. Hamilton
Keyword(s):  
Coastal Region ◽  
Field Work ◽  
Natural Environment Research Council ◽  
East Greenland ◽  
The North ◽  
Tectonic Processes ◽  
Field Investigations ◽  
North Eastern ◽  
Bad Weather ◽  
North Eastern Part

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Chadwick, B., Garde, A. A., Grocott, J., McCaffrey, K. J., & Hamilton, M. A. (2000). Ketilidian structure and the rapakivi suite between Lindenow Fjord and Kap Farvel, South-East Greenland. Geology of Greenland Survey Bulletin, 186, 50-59. https://doi.org/10.34194/ggub.v186.5215 _______________ The southern tip of Greenland is underlain by the Palaeoproterozoic Ketilidian orogen (e.g. Chadwick & Garde 1996; Garde et al. 1998a). Field investigations in the summer of 1999 were focused on the structure of migmatites (metatexites) and garnetiferous granites (diatexites) of the Pelite Zone in the coastal region of South-East Greenland between Lindenow Fjord and Kap Farvel (Figs 1, 2). Here, we first address the tectonic evolution in the Pelite Zone in that region and its correlation with that in the Psammite Zone further north. Then, the structure and intrusive relationships of the rapakivi suite in the Pelite Zone are discussed, including particular reference to the interpretation of the controversial outcrop on Qernertoq (Figs 2, 8). Studies of the structure of the north-eastern part of the Julianehåb batholith around Qulleq were continued briefly from 1998 but are not addressed here (Fig. 1; Garde et al. 1999). The field study was keyed to an interpretation of the Ketilidian orogen as a whole, including controls of rates of thermal and tectonic processes in convergent settings. Earlier Survey field work (project SUPRASYD, 1992–1996) had as its principal target an evaluation of the economic potential of the orogen (Nielsen et al. 1993). Ensuing plate-tectonic studies were mainly funded in 1997–1998 by Danish research foundations and in 1999 by the Natural Environment Research Council, UK. The five-week programme in 1999 was seriously disrupted by bad weather, common in this part of Greenland, and our objectives were only just achieved. Telestation Prins Christian Sund was the base for our operations (Fig. 2), which were flown with a small helicopter (Hughes MD-500).

Tectono-sedimentary model for the evolution of the Silves Group (Triassic, Lusitanian basin, Portugal)

2012 ◽  
Vol 183 (3) ◽  
pp. 203-216 ◽  
Author(s):  
António Ferreira Soares ◽  
José Carlos Kullberg ◽  
Júlio Fonseca Marques ◽  
Rogério Bordalo da Rocha ◽  
Pedro Miguel Callapez
Keyword(s):  
Field Work ◽  
Coarse Grained ◽  
Variscan Orogeny ◽  
Type Region ◽  
The North ◽  
Detailed Structural Analysis ◽  
Sequential Organization ◽  
Eastern Border ◽  
Tensional Stress ◽  
Lusitanian Basin

Abstract At the beginning of the Alpine cycle, the breakup of Pangea lead to the early stages of the North Atlantic opening. In the western Iberian sector of the European margin, the Lusitanian basin starts to evolve bordered eastwards by inherited reliefs from the late episodes of the Variscan orogeny. The base unit, the Silves Group, considered not earlier than the Carnian, is mainly siliciclastic and predominantly formed by arcosarenites to feldspar litarenites, coarse to very coarse-grained (wackes) and pebbly, where the sediment architecture denotes organizations in continental (Conraria, Penela and Castelo Viegas Formations) environments. A first marine episode (Isocyprina Beds of Pereiros Fm.) marks a significant change within the sedimentary record; the uppermost part corresponds to intertidal transitional environments (sabkha). New and detailed field work of sedimentological and structural nature that has been carried out in recent exposures from the type-region of Coimbra-Penela enabled us to make significant observations and to improve data collection. This allowed a full reinterpretation of the paleotectonic and paleogeographical conditions under which the Silves Group and, consequently, the eastern border of the Lusitanian basin, evolved. This study carried out in the type-region also allowed a better understanding of its sequential organization. All units are unconformity bounded by strong influxes of coarse siliciclastics from the Iberian meseta. One of those unconformities (D2b) is an angular unconformity with cartographic expression. Tectonic reconstructions were possible to make after a detailed structural analysis of normal synsedimentary faults. Regional comparisons with Eastern Iberian basins that evolved since Permian times are also discussed. We conclude that the lower red siliciclastic units are older than has been considered until now. Those units were formed in a previous tensional stress pattern of tardi-Variscan affinities, related to megashear dextral kinematics of Permian-Triassic age. We propose that units below D2b unconformity can record a Proto-Lusitanian basin; the Lusitanian basin is younger and evolved mainly after the Triassic-Jurassic limit (Castelo Viegas Fm.) within an E-W extensional context related to Atlantic type basins.

Modern Analogues of Sedimentation of Lower Permian Reservoirs in the Dnieper-Donets Depression

2021 ◽  
Author(s):  
Valentyn Loktyev ◽  
Sanzhar Zharkeshov ◽  
Oleg Gotsynets ◽  
Oleksandr Davydenko ◽  
Mikhailo Machuzhak ◽  
...  
Keyword(s):  
Donets Basin ◽  
Lower Permian ◽  
River Channels ◽  
Current Time ◽  
Meandering Channels ◽  
The North ◽  
Complex Picture ◽  
Middle Carboniferous ◽  
The Indian Ocean ◽  
Desert Dunes

Abstract The paper considers the problematics of identifying proper analogues for understanding carbonate and clastic reservoir distribution and prediction in the Lower Permian and Upper and Lower Carboniferous within the Dnieper-Donets basin. The focus of the exploration team was finding meandering rivers. This choice was proven good in mapping reservoirs and finding traps deeper in the Upper and Middle Carboniferous, although for Permian clastic section the approach was not helpful. The second option was desert dunes, but poor sorting of reservoirs suggests a more complex picture. Analogues such as desert environment is quite logical for describing Lower Permian as aridic climate, with red and brown shales and sands. Lower Permian reservoirs have a moon-like shape in the vertical sections that could be easily mistaken for river channels, but in such a dry climate, it is very likely water flow channels with sporadic hurricane-related activities. Core and logs shows chaotic grain sizes, but more with fine grains with almost no coarse grains. The source of sedimentary material could be mountains of Ukrainian Rock Shield from the South and Voronezh massif from the North. This conceptual model is proposing not to look for meandering channels, but more for braided channels with poorly sorted material. The current time analogue could be the Oman desert between the mountains and peninsula. From satellite images, braided channels are clearly visible in the direction towards the Indian Ocean. The channels’ internal structure is quite heterogeneous. This method suggests exploration targets with possible widths of the channels as big as hundreds of meters and their lengths under 10 and between 10-20 kilometres maximum.

REPEATED TRENDS OF FOLDS AND CROSS-FOLDS IN PALAEOZOIC ROCKS, PARRSBORO, NOVA SCOTIA

1964 ◽  
Vol 1 (3) ◽  
pp. 167-183 ◽  
Author(s):  
W. K. Fyson
Keyword(s):  
Nova Scotia ◽  
Vertical Movements ◽  
Clastic Rocks ◽  
Three Generations ◽  
The North ◽  
North Side ◽  
Two Generations ◽  
Major Fault ◽  
Granitic Intrusions ◽  
Middle Carboniferous

On the north side of a major fault three generations of folds F1, F2, F3 affect pre-Carboniferous phyllites; south of the fault two generations, C1, C2, affect middle Carboniferous clastic rocks. The F1 folds are isoclinal and obscure. The main folds, F2 in the phyllites and C1 in the Carboniferous rocks, trend east-northeast parallel to the fault. F2 are overturned southward and C1 northward, both toward the fault. Cross-folds, F3 in the phyllites and C2 in the Carboniferous rocks, trend northnortheast. Steeply plunging F3 and C2 are asymmetric and Z-shaped in plan profile.The F2 folds in the phyllites, though similar in geometry to folds in the middle Carboniferous rocks, appear, like F1 and F2, to have formed prior to the middle Carboniferous. This is indicated by the occurrence of unfolded Devonian(?) granitic intrusions crossing F3 folds, and a few miles north of the major fault, by middle Carboniferous rocks lying unconformably- above similar intrusions.One possible explanation for the repeated trends, which also accounts for the sense of overturning and asymmetry of the folds, relates the folding to alternating vertical and horizontal movements along the major fault. The vertical movements were followed by gravity sliding toward the fault to produce the main folds, and the horizontal movements, repeatedly dextral in sense, resulted in the Z-shaped cross-folds.

Kean Miltos: The Well-Known Iron Oxides of Antiquity

1997 ◽  
Vol 92 ◽  
pp. 359-371 ◽  
Author(s):  
E. Photos-Jones ◽  
A. Cottier ◽  
A. J. Hall ◽  
L. G. Mendoni
Keyword(s):  
Iron Oxides ◽  
Analytical Techniques ◽  
Field Work ◽  
Archaeological Record ◽  
The North ◽  
Naturally Occurring ◽  
Physico Chemical ◽  
Wide Range ◽  
Industrial Mineral

The island of Kea in the North Cyclades was well known in antiquity for its miltos, a naturally occurring red iron oxide valued for its colour and wide range of applications. By combining geological field work, physico-chemical analytical techniques, simulation (heating) experiments as well as simple laboratory tests, this paper describes the study of Kean iron oxides in an attempt to characterize this material which is still largely elusive in the archaeological record. The present work corroborates previous observations about the superior quality of some Kean iron oxides. Furthermore, it puts forward the hypothesis that miltos may have been considered an industrial mineral, and as such may have been used as an umbrella term for a variety of materials including mineralogically distinct purple as well as red iron oxides.

scholarly journals Notes on some Lower Palaeozoic to Tertiary faunas from eastern North Greenland

1974 ◽  
Vol 65 ◽  
pp. 18-23
Author(s):  
J.S Peel ◽  
P.R Dawes ◽  
J.C Troelsen
Keyword(s):  
Field Work ◽  
The South ◽  
Initial Field ◽  
North East ◽  
The North ◽  
Lower Palaeozoic ◽  
North Greenland

The north-east 'corner' of Greenland is geologically probably the least known region in North Greenland. Various expeditions have visited the coastal parts but geological detail, particularly faunal information, has remained surprisingly scarce. Initial field work by Koch (1923, 1925) and Troelsen (1949a, b, 1950) showed that a Precambrian to Silurian section - unfolded in the south, folded in the north - was unconformably overlain by a Carboniferous to Tertiary section, now referred to as the Wandel Sea basin (Dawes & Soper, 1973).

scholarly journals EVALUATION OF ANTIMICROBIAL AND ANTIPROLIFERATIVE ACTIVITIES OF ACTINOBACTERIA ISOLATED FROM THE SALINE LAGOONS OF NORTHWEST PERU

2020 ◽  
Author(s):  
Rene Flores Clavo ◽  
Nataly Ruiz Quiñones ◽  
Álvaro Tasca Hernandez ◽  
Ana Lucia Tasca Gois Ruiz ◽  
Lucia Elaine de Oliveira Braga ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Antiproliferative Activity ◽  
Extreme Environments ◽  
Extreme Environment ◽  
Small Cells ◽  
E Coli ◽  
The North ◽  
Salt Flats ◽  
Multiple Drugs ◽  
Antiproliferative Activities

AbstractThe unexplored saline lagoons of the north of Peru harbor a rich microbiome, due to reported studies of different extreme environments around the world. In these regions, there are several ecosystems and microhabitats not yet explored, and little is known about the diversity of actinobacteria and other microorganisms. We suggest that the endemic bacteria present in this extreme environment could be source of active molecules with anticancer, antimicrobial, antiparasitic properties. Using phenotypic and genotypic characterization techniques including the 16S rRNA were identified into the genera Streptomyces 39 (78%), Pseudonocardia 3 (6%), Staphylococcus 4 (8%), Bacillus 2 (4%), and Pseudomonas 2 (4%). All isolated bacteria for the genotypic data were preliminarily identified. Actinobacteria strains were found dominantly in both sites (Lagoon1-3 = 16 isolates and lagoon 4 = 12 isolates). Phylogenetic analysis revealed that 28 isolates were exclusively affiliated to eleven different clusters of Actinobacteria of the major genus Streptomyces. Three Streptomyces sp. strains M-92, B-146, and B-81, were tested for antibacterial and antiproliferative activities. The results showed antiproliferative activities against three tumor cell lines, U251 glioma; MCF7 breast; NCI-H460 lung non-small type of cells, and the antibacterial activity to Staphylococcus aureus ATCC 6538, E. coli ATCC 10536, and Acinetobacter baumanni AC-972 which is resistant to multiple drugs. The promising results belong to Streptomyces sp. B-81 strain in the R2A medium using a doxorubicin with control positive, the best result was from the latter (TGI = 0,57 µg/mL) for glioma; NCI-H460 lung of type non-small cells (TGI = 0,61 µg/mL), and breast cancer (TGI =0,80 µg/mL), this strain was selected to be fractionated because it had better antiproliferative and antibacterial activity, and its fractions were evaluated concerning antiproliferative activity against nine types of tumor cells and one non-tumor. The methanolic fraction showed a better result in the antiproliferative activity and was able to inhibit U251 (glioma) (TGI = 38.3 µg/mL), OVCAR-03 (ovary) (TGI = 62.1 µg/mL), and K562 (leukemia) (TGI = 81.5 µg/mL). The methanol 50% - acetate 50% fraction (Fraction 4) inhibited U251 (glioma) (TGI = 73.5 µg/mL) and UACC-62 (melanoma) (TGI = 89.4 µg/mL). Moreover, the UHPLC-MS/MS data and molecular networking of Streptomyces sp. B-81 isolate extract revealed the production cholic acid, Lobophorin A, Lobophorin B, Lobophorin E, Lobophorin K and compound 6. Extremophilic environments such as the Mórrope and Bayovar Salt Flats are promising sources of new bacteria with promising pharmaceutical potential; These compounds could be useful to treat various infectious diseases or even some type of cancer.

scholarly journals Field work in the north of the Ivisârtoq region, inner Godthåbsfjord, southern West Greenland

1983 ◽  
Vol 115 ◽  
pp. 49-56
Author(s):  
B Chadwick ◽  
M.A Crewe ◽  
J.F.W Park
Keyword(s):  
Field Work ◽  
Geological Survey ◽  
West Greenland ◽  
North West ◽  
The North ◽  
Field Investigations ◽  
New Findings ◽  
Host Rocks

The programme of field investigations in the north of the Ivisartoq region begun in 1981 by Chadwick & Crewe (1982) was continued in 1982. Julia Park began mapping the Taserssuaq granodiorite, its host rocks and the Ataneq fault in the north-west. Dur team was joined by D. Bellur, Geological Survey of India, nominally as an assistant. In this report we present only summary notes of new findings relevant to the interpretation of the geometry and chronology of this segment of the Archaean crust in southern West Greenland. We use the established terminology for the Archaean rocks of the Godthåbsfjord region.

scholarly journals Studies on the onshore hydrocarbon potential in East Greenland 1986-87: field work from 72° to 74°N

1987 ◽  
Vol 135 ◽  
pp. 72-81
Author(s):  
C Marcussen ◽  
F.G Christiansen ◽  
P.-H Larsen ◽  
H Olsen ◽  
S Piasecki ◽  
...  
Keyword(s):  
Thermal History ◽  
Sedimentary Basins ◽  
Field Work ◽  
Source Rocks ◽  
Hydrocarbon Potential ◽  
East Greenland ◽  
The North ◽  
Hydrocarbon Traps ◽  
Subsidence History ◽  
Tectonic Study

A study of the onshore hydrocarbon potential of central and northem East Greenland was initiated in 1986. Field work was carried out from early July to mid August covering the region between Kong Oscar Fjord and Kejser Franz Joseph Fjord (fig. 1). In 1987 field activities will continue further to the north, eventually reaching Danmarkshavn (77°N). The programme is a continuation of the 1982-83 investigations in Jameson Land (Surlyk, 1983; Surlyk et al., 1984a) and is part of a regional programme comprising petroleum geological studies of all sedimentary basins in Greenland (Larsen & Marcussen, 1985; Larsen, 1986). The aim of the two-year field study followed by laboratory analyses is: (1) to study the presence and distribution of potential hydrocarbon source rocks in the region; (2) to evaluate the thermal history and maturity pattern of the region including the thermal effect of Tertiary intrusions and volcanics; (3) to make a stratigraphic, sedimentological and tectonic study of the region with special emphasis on subsidence history, reservoir formation and potential hydrocarbon traps.

scholarly journals The geology of the north-eastern corner of Greenland - photogeological studies and 1993 field work

1994 ◽  
Vol 161 ◽  
pp. 21-33
Author(s):  
H.F Jepsen ◽  
J.C Escher ◽  
J.D Friderichsen ◽  
A.K Higgins
Keyword(s):  
Field Work ◽  
Tectonic Activity ◽  
Mobile Belt ◽  
North East ◽  
The North ◽  
Upper Proterozoic ◽  
North Eastern ◽  
Field Season ◽  
Upper Boundary ◽  
Middle Proterozoic

Late Archaean and Early Proterozoic crust-forming events in North-East and eastern North Greenland were succeeded by Middle Proterozoic sedimentation and volcanic activity; Late Proterozoic through Tertiary sedimentation was interrupted by several periods of tectonic activity, including the Caledonian orogeny in East Greenland and the Mesozoic deformation of the Wandel Hav mobile belt. Photogeological studies helped pinpoint areas of special interest which were investigated during the short 1993 field season. Insights gained during field work include: the nature of the crystalline basement terrain in the Caledonian fold belt, redefinition of the upper boundary of the Upper Proterozoic Rivieradal sandstones, revision of Caledonian nappe terminology, and the northern extension of the Caledonian Storstrømmen shear zone.

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