Lower Carboniferous Bryozoa from some localities in Sauerland, Germany

2005 ◽  
pp. 59-72
Keyword(s):  
Lower Carboniferous

Lithostratigraphy of the Kweekvlei Formation (Witteberg Group), Cape Supergroup

2017 ◽  
Vol 120 (3) ◽  
pp. 421-432 ◽  
Author(s):  
C. Browning ◽  
M. Reid
Keyword(s):  
South Africa ◽  
Transition Zone ◽  
Distal Part ◽  
Vascular Plant ◽  
Trace Fossil ◽  
Plant Debris ◽  
Lower Carboniferous ◽  
Fossil Assemblage ◽  
Low Diversity ◽  
Storm Wave

AbstractThe Lower Carboniferous, probably Tournaisian, Kweekvlei Formation is part of the Witteberg Group (Cape Supergroup) of South Africa. Together with the overlying Floriskraal Formation, it forms an upward-coarsening succession within the Lake Mentz Subgroup. Sedimentary features of the Kweekvlei Formation suggest deposition in a storm-wave dominated marine setting, within the storm-influenced, distal part of an offshore transition zone environment. This predominantly argillaceous formation preserves a low diversity trace fossil assemblage. Reworked vascular plant debris (including the problematic genus Praeramunculus sp.) and a shark spine have been reported for the Kweekvlei Formation. There are no known stratigraphic equivalents in South Africa.

The Mississippian (Lower Carboniferous) in northeast Spitsbergen (Svalbard) and a re-evaluation of the Billefjorden Group

2012 ◽  
Vol 163 (3) ◽  
pp. 293-308 ◽  
Author(s):  
Christian Scheibner ◽  
Christoph Hartkopf-Fröder ◽  
Dierk Blomeier ◽  
Holger Forke
Keyword(s):  
Lower Carboniferous

scholarly journals II.—Description of a Fossil Shark (Ctenacanthus costellatus) from the Lower Carboniferous Rocks of Eskdale, Dumfriesshire

1884 ◽  
Vol 1 (1) ◽  
pp. 3-8 ◽  
Author(s):  
R. H. Traquair
Keyword(s):  
Lower Carboniferous ◽  
General Organization

The deficiency of our knowledge of the organization and configuration of the Palaeozoic Selachii is an unfortunate fact too well known to biologists to render it necessary for me to dilate upon here. Immense numbers of genera and species have been founded upon detached teeth and spines; but as yet very few specimens have occurred, which threw any light upon the general organization and configuration of the ancient possessors of these now scattered relics.

Planalvus (Brachiopoda, Athyridida) from the Lower Devonian of the Armorican Massif, northwest France

1994 ◽  
Vol 68 (3) ◽  
pp. 451-460 ◽  
Author(s):  
Patrick R. Racheboeuf ◽  
Paul Copper ◽  
Fernando Alvarez
Keyword(s):  
New Species ◽  
North America ◽  
Lower Devonian ◽  
Eastern North America ◽  
Lower Carboniferous ◽  
Armorican Massif ◽  
A New Species

Cryptonella? cailliaudi Barrois, 1889, from the Lower Devonian of the Armorican Massif, is tentatively assigned to the athyridid brachiopod genus Planalvus Carter, thus far known only from the Lower Carboniferous of eastern North America. In addition, a new species, Planalvus rufus, is described from the Bois-Roux Formation (Pragian) of Brittany, France. These French species are small brachiopods with complex spiralial and jugal structures, which permit assignment to the order Athyridida.

Interpretation of Pb isotope compositions of galenas from the Midland Valley of Scotland and adjacent regions

1984 ◽  
Vol 75 (2) ◽  
pp. 85-96 ◽  
Author(s):  
John Parnell ◽  
Ian Swainbank
Keyword(s):  
Lower Devonian ◽  
Lead Isotope ◽  
Sedimentary Rocks ◽  
Isotope Ratios ◽  
Igneous Rocks ◽  
Pb Isotope ◽  
Lower Carboniferous ◽  
Granite Magma ◽  
Lower Palaeozoic ◽  
Caledonian Granite

ABSTRACTThe lead isotope compositions of 61 galenas from central and southern Scotland vary markedly between different regions. Most galenas from the southern Grampian Highlands yield isotope ratios (206Pb/204Pb 17·77 ± 0·25, 207Pb/204Pb 15·47 ± 0·05, 208Pb/204Pb 37·63 ± 0·26) less radiogenic than those from Midland Valley galenas (18·22 ± 0·12, 15·55 ± 0·05, 38·13 ± 0·14) whilst galena lead from the Southern Uplands (18·28 ± 0·12, 15·56 ± 0·03, 38·21 ± 0·18) is more radiogenic than that from the southern Midland Valley (18·12 ± 0·06, 15·52 ± 0·02, 38·06 ±0·10). The change in isotopie composition across the Highland Boundary fault reflects the presence or absence of Dalradian rocks which included a magmatic component of lead. Galenas from the Dalradian sequence in Islay, where igneous rocks are lacking, have a composition (18·14±0·04, 15·51±0·01, 37·90±0·02) more like Midland Valley galenas. In the Southern Uplands, galenas yield lead isotope ratios similar to those of feldspars from Caledonian granite (18·30 ± 0·14, 15·57 ± 0·04, 37·96 ± 0·15) analysed by Blaxland et al. (1979). The similar ratios reflect the incorporation of Lower Palaeozoic sedimentary rocks into the granite magma, rather than a granitic source for the mineralisation. The granites were then thermal-structural foci for later mineralising fluids which leached metals from the surrounding rocks. Within the Midland Valley, galenas hosted in Lower Devonian-Lower Carboniferous lavas are notably more radiogenic (18·31 ±0·12, 15·58 ± 0·06, 38·20 ± 0·16) than sediment-hosted galenas (18·14 ± 0·07, 15·52 ± 0·02, 38·08 ± 0·10). The Devonian lavas at least may have inherited lead from subducted (? Lower Palaeozoic) rock incorporated in the primary magma.

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