Namurian Deposits Research Articles

Geology and thermal maturity of Namurian deposits in the Němčičky Sub-basin as the South-eastern continuation of the Upper Silesian Coal Basin (Czech Republic)

The southernmost documented occurrences of Namurian coal-bearing strata can be found in the Němčičky area, SE Moravia, that is considered to be the southern continuation of the Upper Silesian Coal Basin. Since the south-eastern Moravia belongs to the most prospective areas in terms of hydrocarbon exploration and production in the Czech Republic and Namurian deposits are considered to be one of the potential source rocks, there was a systematic evaluation of the southernmost occurrence of coal-bearing Carboniferous deposits in the Czech Republic during the hydrocarbon exploration within the area with regard to the regional geological setting and thermal maturity. 2D and high-quality 3D seismic surveys were used for a detailed thermal maturation analysis and a determination of the regional situation of heavily faulted/eroded Namurian strata. Cores and cuttings of coal and siltstones were used from 8 boreholes to investigate and measure the vitrinite reflectance; the lithology and petrography definition was also done based on thin sections. All new measurements were compared with archived data and older studies. In the Němčičky Sub-basin, the complete sedimentary succession occurs as part of typical cyclic development, starting with basal conglomerates and followed by sandstones alternating with claystones, siltstones and coal seams of marine and transitional origin. Samples from the Nikolčice-Kurdějov ridge are showing significantly lower vitrinitte reflectance values with respect to their depths than those from the Nesvačilka graben; this fact is supporting the distinctive lateral movement along the western Nesvačilka fault as presumed from the seismic interpretation. Dominant source from “immature” orogen is combined with the source from the “mature” continetal block i.e. opposite margin of the basin. The seismic interpretation shows that the thicknesses of Namurian deposits are not decreasing at all towards the recently deeper positions; accordingly, it is suggested that it is right within this erosionally untouched accommodational space of the Němčičky Sub-basin where we can find the interconnection to the USCB in the north.

A revised palynozonation of British Namurian deposits and comparisons with eastern Europe

Research Article| January 01, 2004 A revised palynozonation of British Namurian deposits and comparisons with eastern Europe Bernard Owens; Bernard Owens 1Palynological Research Facility, Department of Animal and Plant Sciences University of Sheffield, Western Bank, Sheffield S10 2TN, UK2British Geological Survey, Keyworth, Nottingham NG12 5GG, UK email: d.mclean@sheffield.ac.uk Search for other works by this author on: GSW Google Scholar Duncan McLean; Duncan McLean 1Palynological Research Facility, Department of Animal and Plant Sciences University of Sheffield, Western Bank, Sheffield S10 2TN, UK Search for other works by this author on: GSW Google Scholar David Bodman David Bodman 1Palynological Research Facility, Department of Animal and Plant Sciences University of Sheffield, Western Bank, Sheffield S10 2TN, UK Search for other works by this author on: GSW Google Scholar Micropaleontology (2004) 50 (1): 89–103. https://doi.org/10.2113/50.1.89 Article history received: 30 Sep 2003 accepted: 07 Dec 2003 first online: 06 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Bernard Owens, Duncan McLean, David Bodman; A revised palynozonation of British Namurian deposits and comparisons with eastern Europe. Micropaleontology 2004;; 50 (1): 89–103. doi: https://doi.org/10.2113/50.1.89 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyMicropaleontology Search Advanced Search Abstract Existing schemes for the palynozonation of the Namurian deposits in western Europe require updating to reflect improvements in both independent biostratigraphical calibration and species distribution data. New biozonation proposals are presented which include the accurate positioning of all biozonal boundaries and the establishment of new sub-biozonal units within the Pendleian – Alportian sections.The base of the renamed Cingulizonates cf capistratus – Bellispores nitidus (CN) Biozone is placed within the late Brigantian and a new unit , the C. cf. capistratus (Cc) Sub-Biozone, with an upper boundary coincident with the Viséan – Namurian Stage boundary is proposed. The Pendleian part of the revised CN Biozone is established as the Verrucosisporites morulatus (Vm) Sub-Biozone.Additional data from the Lycospora subtriquetra – Kraeuselisporites ornatus (SO) Biozone, in the interval adjacent to the proposed Mid-Carboniferous Boundary, permits the establishment of L. subtriquetra – Apiculatisporis variocorneus (SV)Sub-Biozone in the upper part of the Arnsbergian Stage and the L. subtriquetra – Cirratriradites rarus (SR) Sub-Biozone which occupies the Chokierian and most of the Alportian stages. The base of the Crassispora kosankei – Grumosisporites varioreticulatus (KV) Biozone is repositioned into the upper part of the Alportian Stage.Comparable assemblages described from the Silesian Coal Basins of Poland are discussed and correlations between the palynozonations of both areas are suggested. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

A revised palynozonation of British Namurian deposits and comparisons with eastern Europe

Abstract Existing schemes for the palynozonation of the Namurian deposits in western Europe require updating to reflect improvements in both independent biostratigraphical calibration and species distribution data. New biozonation proposals are presented which include the accurate positioning of all biozonal boundaries and the establishment of new sub-biozonal units within the Pendleian – Alportian sections. The base of the renamed Cingulizonates cf capistratus – Bellispores nitidus (CN) Biozone is placed within the late Brigantian and a new unit, the C. cf. capistratus (Cc) Sub-Biozone, with an upper boundary coincident with the Visean – Namurian Stage boundary is proposed. The Pendleian part of the revised CN Biozone is established as the Verrucosisporites morulatus (Vm) Sub-Biozone. Additional data from the Lycospora subtriquetra – Kraeuselisporites ornatus (SO) Biozone, in the interval adjacent to the proposed Mid - Carboniferous Boundary, permits the establishment of L. subtriquetra – Apiculatisporis...

The Ancenis Terrane: an exotic duplex in the Hercynian belt of Armorica, western France

The Ancenis Terrane, bordering the Loire, France, consists of Precambrian Brioverian basement and three Paleozoic sedimentary sequences: marine Ordovician to Devonian shelf sediments; Lower Carboniferous synorogenic intermontane sediments (the ‘Culm’); and coal-bearing Namurian deposits. The terrane is completely bound by faults, and its geology is in marked contrast with that of its neighbours. New data and observations along the terrane's southern boundary show that the Ordovician–Devonian sequence occupies a transpressional shear zone, and can be described as a tectonic mélange. The Culm outcrop, previously interpreted as a sinistral pull-apart structure, is reinterpreted as a Lower Carboniferous dextral pull-apart, and it is shown that Carboniferous transpression and thrusting remodelled the pull-apart basin into its present ‘mica-fish’ shape. With its remarkable concentric structure, and within a plate tectonic setting of mega dextral displacements along the northern boundary of Gondwana, the Ancenis Terrane can be interpreted as an exotic duplex.

Deep borehole evidence for a southward extension of the Early Namurian deposits near Němčičky, S. Moravia, Czech Republic: implication for rapid coalification

Abstract Unexpected Early Namurian (Namurian A) sediments were identified in several boreholes in the vicinity of Němčičky (the Němčičky basin), south Moravia. Coal fragments were recovered from the boreholes Něm 1, 2, 5 and 6. These fragments come partly from in situ coal seams, partly from eroded coal seams and partly from coalified logs. Although these fragments were recovered from depths of 2690.9 m (Něm 5) to 4803 m (Něm 1), their mean reflectance ( R 0 ) is 0.57% up to 0.9% which corresponds to subbituminous to high volatile bituminous coal. The very low rank of the coal at these depths argues for very fast coalification of the coal fragments most likely during the Carboniferous. The rank of the coal is believed not to have been affected by later burial beneath Jurassic sediments or by tectonic burial under Carpathian nappes.

Namurian miospores from China and their correlation with Europe and North America

Late Carboniferous deposits in Jingyuan, northwest China, were palynologically subdivided into TA, VR, SB, KM, BP, AS and TG miospore Zones, ranging from Namurian A to Westphalian A, based on the associated faunal evidence (mainly ammonoids, conodonts and fusulinids). Some more important characters and/or peculiarities of some of the components in the palynoflora in the Namurian deposits of Jingyuan, China are documented. The miospores for example assigned to Monoletes (mainly Laevigatosporites), with their known occurrence in lower frequency in the Tsingyuan Formation, increase markedly from the base of the BP miospore Zone (equivalent to R2-G1) of the upper part of the Hongtuwa Formation. Disaccites, including representatives of Limitisporites, Gardenasporites, Klausipollenites, Alisporites, Platysaccus, Illinites, Jugasporites and Vestigisporites, have their earliest records in the VR miospore Zone (equivalent to E2) of the upper part of the Tsingyuan Formation, and develop rapidly in the BP Zone. The stratigraphical distribution of these two important taxa is significantly different from their known occurrence in western Europe and North America, where the first appearance of Disaccites (non striatiti) and the first quantitatively significant increase of Laevigatosporites in coal-bearing peat deposits take place in the Westphalian within the Euramerican flora.Comparisons of the Namurian miospore assemblages of North America and Europe with those of China suggest that the KM and AS + TG Zones in Jingyuan can be correlated with the KV and SS Zones of the British palynological zonation, respectively. Other correlations of miospore zones from Jingyuan and other areas of the Northern Hemisphere are also suggested and discussed. A number of species, including Simozonotriletes verrucus Zhu, S. sinensis Zhu, Stenozonotriletes rotundus Wang emend. Zhu, S. circularis Zhu, Reinschospora granifer (Gao) Zhu and Procoronaspora odontopetala Zhu, are regarded as endemic species for Jingyuan and characterise the differences of the Namurian palynoflora between Jingyuan and other areas. The palynological differences combined with the peculiarities of fossil plants associated with the miospores imply that the differentiation of the Cathaysian from the Euramerican floras came into existence no later than the early Namurian rather than the latest Carboniferous which previously was considered the most probable time for the origin of the Cathaysian flora by Chinese palynologists.

A revised palynological sub-division of the Namurian of Jingyuan, northwest China

Studies carried out during the last decade have permitted the establishment of palynological zonal schemes for the Namurian deposits in China. The palynological zones proposed in this paper are based on material from Jingyuan, northwest China, where the exposures are well-developed without any apparent break and miospores are abundant and well preserved allowing the recognition of successive Namurian miospore zones. Seven miospore assemblage zones, i.e. Zones TA, VR, SB, KM, BP, AS and TQ, equivalent to goniatite Zones E 1, E 2, H, R 2, R 2-G 1, lower G 2 and upper G 2, respectively, according to the ammonoids and conodonts associated with them, covering the age from Namurian A to early Westphalian A, have been described. Some correlations of zones recognized in Jingyuan and those of Western Europe are briefly discussed.

PALYNOLOGICAL DIVISION OF THE NAMURIAN OF NORTHERN ENGLAND AND SCOTLAND

SUMMARY Studies carried out during the last decade have permitted the establishment of palynological zonal schemes for the Dinantian and Westphalian series in Britain. The present paper proposes a series of five concurrent assemblage range zones for the Namurian deposits of northern England and Scotland based on the results obtained from a number of widely-spaced sections. The scheme is defined so as to facilitate the establishment of one continuous set of palynologically defined zones for the entire Carboniferous deposits in Britain. The principal components of each of the zones are documented and details of local stratigraphical distribution are supplied. Attempts have been made to integrate the principal macropalaeontological data in order that this zonal scheme can be equated with others defined on different biostratigraphical criteria.

Comparison of namurian sediments of the central pennines, England, and recent deltaic deposits

This paper makes a general comparison of sediments of the Namurian delta in the central Pennines and sediments of Recent deltas. Some of the detailed evidence on which this comparison is based has been presented elsewhere and is only summarised here. As a result of the comparison it is concluded that the coarse sandstone of the Namurian deposits were laid down by rivers, and the sandstones of intermediate grain-size (0.3–0.1 mm median diameters) are tidal deposits. The marine shales of the Namurian, and their associated non-marine shales, resemble the deposits of tranquil embayments near modern deltas, and the laminated fine siltstones that usually succeed the marine shales closely resemble present-day pro-delta silts. The importance of compaction and of diachronism is stressed.

Sur quelques lepidodendrees du Namurien de la Basse-Loire

Abstract The lepidodendron genus Sigillaria, rare to the Namurian (Carboniferous), is represented by abundant forms of two species in the Namurian of the lower Loire region, France. Microspores similar to those described as Lepidophloios laricinus also occur in the Namurian deposits of the region.