scholarly journals Caledonian foreland basin sedimentation: A new depositional model for the Upper Silurian‐Lower Devonian Lower Old Red Sandstone of the Midland Valley Basin, Scotland

2020 ◽  
Author(s):  
Zoe McKellar ◽  
Adrian J. Hartley
Keyword(s):  
Lower Devonian ◽  
Foreland Basin ◽  
Depositional Model ◽  
Red Sandstone ◽  
Upper Silurian

Synchronology

1985 ◽  
Vol 309 (1138) ◽  
pp. 11-27 ◽  
Keyword(s):  
Sea Level ◽  
Quantitative Methods ◽  
Lower Devonian ◽  
Practical Interest ◽  
Radiometric Dating ◽  
Vertebrate Evolution ◽  
Significant Evidence ◽  
Red Sandstone ◽  
Level Curves ◽  
Upper Silurian

Radiometric dating cannot as yet approach the resolution obtainable in Silurian and Devonian biostratigraphy. Progress towards achievement of a global standard for the Wenlock and Emsian interval (against which evolution and environment must be seen) is reviewed. In biostratigraphical correlation with this standard certain groups are especially useful. Correlation between marine Upper Silurian and Lower Devonian rocks and their equivalents in the Old Red Sandstone magnafacies presents particular problems and yet the latter provides significant evidence of plant and vertebrate evolution at this time. The recognition of widespread physical events such as volcanic episodes may sometimes prove useful. Sea level curves seldom provide a precise synchronology not achievable through biostratigraphy. Quantitative methods of correlation are so far of theoretical rather than practical interest.

scholarly journals II - The Acanthodian fishes

1937 ◽  
Vol 228 (549) ◽  
pp. 49-146 ◽  
Keyword(s):  
Lower Devonian ◽  
Good Evidence ◽  
Caudal Fin ◽  
Red Sandstone ◽  
The World ◽  
Upper Silurian ◽  
Devonian Age ◽  
Fin Spines

The Acanthodian fishes form one of the most sharply demarcated and recognizable groups of vertebrate fossils. Their characteristic squamation of square, exceedingly minute ganoid scales, and the fact that all the fins except the caudal fin are supported by large anterior spines, distinguish them sharply from all other fishes, and enable even fragmentary specimens to be recognized without doubt. They are worldwide in distribution, and their range in tim e is thus known with considerable certainty. The first fragments, attributed on very good evidence to the group, are isolated fin spines, found in Upper Silurian rocks perhaps not earlier than the Downtonian, which seem to be identical with those found in complete fishes of Lower Devonian age. The group was more varied in structure and played a larger part in the world in Lower Devonian times than at any other period. Even in the Middle Old Red Sandstone the range in structure had been reduced, and by Carboniferous times very few forms remained.

scholarly journals The Cosheston Group (Lower Old Red Sandstone) in southwest Wales: age, correlation and palaeobotanical significance

1998 ◽  
Vol 135 (3) ◽  
pp. 397-412 ◽  
Author(s):  
C. H. WELLMAN ◽  
R. G. THOMAS ◽  
D. EDWARDS ◽  
P. KENRICK
Keyword(s):  
Lower Devonian ◽  
New Age ◽  
Early Devonian ◽  
Red Sandstone ◽  
South Wales ◽  
Upper Silurian ◽  
Devonian Age ◽  
Sandstone Facies

Upper Silurian–Lower Devonian ‘Lower Old Red Sandstone’ facies deposits cropping out in southwest Wales are poorly age-constrained and difficult to correlate. Spore assemblages have been recovered from sequences of these deposits belonging to the lower part of the Cosheston Group. The spore assemblages are equated with the breconensis–zavallatus and polygonalis–emsiensis Spore Assemblage Biozones and indicate an early Devonian age (late Gedinnian (late Lochkovian)–Siegenian (Pragian)). The new biostratigraphical data enable correlation of the lower part of the Cosheston Group with the Senni Beds from the main outcrop of the Lower Devonian in South Wales and the Welsh Borderland. In addition, the new age data and stratigraphical correlation place important plant megafossil assemblages from the Cosheston Group and Senni Beds in a more secure stratigraphical framework, thus facilitating comparisons with other Lower Devonian plant megafossil assemblages and enhancing palaeobotanical understanding. Evidence from palynofacies analysis supports sedimentological interpretations which suggest that the ‘Lower Old Red Sandstone’ facies deposits belonging to the Cosheston Group accumulated in a continental fluviatile environment.

Notes of a Geologist in Ireland During August and September, 1857

The Geologist ◽  
1858 ◽  
Vol 1 (8) ◽  
pp. 330-335
Author(s):  
W. S. Symonds
Keyword(s):  
Lower Cambrian ◽  
Red Sandstone ◽  
Upper Silurian ◽  
Cover Up

On leaving Dublin, we travelled northwards, for the purpose of examining the carboniferous rocks, and visiting the magnificent collection of fossil-fishes in the museum of the Earl of Enniskillen; we then journeyed south for Killarney and the Dingle district, but as it may be more convenient to the reader to travel geologically, we will reverse the order of our journey, and visit the Upper Silurian and Old Red Sandstone districts before we examine the carboniferous deposits.The lower Cambrian rocks of Wales, of which the Oldhamia-schists of Ireland are believed to be the equivalents, pass upwards by insensible gradations into the Lingula-flags, to which they are altogether conformable. The Lingula-flags are reckoned to be four or five thousand feet thick, and the Llandeilo or Builth-beds, which cover up these, are probably as thick; but geologists are, as yet, uncertain whether they possess in Ireland any true equivalents either of the Lingula-flags or of the Llandeilo and Builth deposits. There are, however, fossiliferous rocks of the Bala and Caradoc age in Ireland similar to those which, in Wales, succeed conformably to the Llandeilo and Builth beds, and they may be examined at Courtown, in the county of Wicklow, and again at Tramore, south of Waterford. They are unconformable to the rocks below, which are undoubtedly Cambrian, and thence, we imagine, has arisen the suspicion that the Lingula-beds and Llandeilo-flags have never been deposited in Ireland, or that if they were, they have been denuded and swept away before the deposition of the Bala or Caradoc strata.

scholarly journals Stauromatidium and Stauromatidiidae, new genus and family of Upper Silurian and Lower Devonian rugose corals

1982 ◽  
Author(s):  
A E H Pedder ◽  
W A Oliver
Keyword(s):  
Lower Devonian ◽  
New Genus ◽  
Rugose Corals ◽  
Upper Silurian

Lower Devonian plant and spore assemblages from Lower Old Red Sandstone strata of Tredomen Quarry, South Wales

2011 ◽  
Vol 165 (3-4) ◽  
pp. 183-208 ◽  
Author(s):  
Jennifer L. Morris ◽  
John B. Richardson ◽  
Dianne Edwards
Keyword(s):  
Lower Devonian ◽  
Red Sandstone ◽  
South Wales

Devonian

1992 ◽  
Vol 13 (1) ◽  
pp. 57-66 ◽  
Author(s):  
B. J. Bluck ◽  
J. C. W. Cope ◽  
C. T. Scrutton
Keyword(s):  
Lower Devonian ◽  
Quaternary System ◽  
Upper Devonian ◽  
Type Locality ◽  
System Boundary ◽  
Red Sandstone ◽  
Stratotype Section ◽  
Lacustrine Facies ◽  
Selection Of ◽  
Upper Boundary

AbstractThe Devonian System was the first pre-Quaternary system to have its base established at an internationally ratified Global Stratotype Section and Point (GSSP). The base of the System was defined at the base of the Monograptus uniformis Biozone at Klonk in Czechoslovakia (McLaren 1977). The upper boundary of the System is fixed by the base of the Carboniferous, which has been recently ratified in a GSSP at La Serre, Herault, France, at a point coincident with the first appearance of the conodont Siphonodella sulcata.Series. GSSPs have now been designated to define the bases of the Middle and Upper Devonian Series (that of the Lower Devonian being automatically defined by the System boundary).Stages. Consequent upon the selection of a Czech type section for the basal boundary stratotype of the System, the Germanic stages for the lowest parts of the Devonian were no longer appropriate and Lochkovian and Pragian stages have now been formally defined with stratotypes ratified by the I.U.G.S.Devon, the nomenclatorial type locality for the Devonian System (Sedgwick & Murchison 1839) is a region of great tectonic complexity and has not provided suitable sections on which to base international correlations. However, the rocks are frequently richly fossilferous and firm correlations can now be established with the intensively studied developments of the Devonian in Belgium and Germany.Northwards from Devon are found large tracts of the predominantly fluviatile and lacustrine facies which characterizes the Old Red Sandstone. Correlation between the marine Devonian rocks of southwest England and the

Arthropod ichnofauna of the Old Red Sandstone at Dunure and Montrose, Scotland

1985 ◽  
Vol 76 (2-3) ◽  
pp. 287-297 ◽  
Author(s):  
Elaine F. Walker
Keyword(s):  
Lower Devonian ◽  
Trace Fossils ◽  
Red Sandstone

ABSTRACTSediments which occur frequently within Lower Devonian andesites of the Midland Valley of Scotland have so far yielded trace fossils in only two areas: Dunure, Ayrshire and Montrose, Angus.Smith (1909) interpreted the trace fossils from Dunure as representing an “Upland Fauna” and he named 23 new ichnogenera. Re-examination of his localities and specimens suggests that the environment was a shallow ephemeral lake and when sedimentological and preservational factors, size, behavioural variation and synonymy are taken into account, only 8 ichnogenera are here considered valid. These are redefined as Siskemia, Stiaria, Danstairia, Keircalia, Stiallia, Isopodichnus (=Archatomia Smith), Mermia and Merostomichnites. The Montrose ichnofauna of 5 ichnogenera includes a large arthropod trackway Mitchellichnus ferrydenensis gen. and sp. nov.The trackways from both localities appear to have been formed by various merostomes, crustaceans and possibly early myriapods. The habitat was essentially aquatic although some arthropods may have been amphibious.

scholarly journals III.—On the Occurrence of Haliserites in the Upper Silurian and Upper Devonian Rocks of Victoria, Australia

1908 ◽  
Vol 5 (10) ◽  
pp. 438-440
Author(s):  
Fredk Chapman
Keyword(s):  
Upper Devonian ◽  
Fossil Plant ◽  
Red Sandstone ◽  
Fossil Remains ◽  
Upper Silurian

During the last few years there have passed through my hands for determination many specimens of a twig-like fossil-plant from the highest Silurian flaggy-sandstones of Victoria. These were usually too fragmentary to afford any very decided evidence as to their affinity, although their surfaces showed a close-textured and well-defined structure, referable to that of prosenchymatous wood-cells, and the stem had a definite central vascular axis, such as was first noticed by Hugh Miller in similar fossil remains from the Old Red Sandstone of Scotland.

Sign in / Sign up

Export Citation Format

Share Document