scholarly journals II.—On Solenopora garwoodi, sp. nov., from the Lower Carboniferous in the North-West of England

1913 ◽  
Vol 10 (7) ◽  
pp. 289-292 ◽  
Author(s):  
George J. Hinde
Keyword(s):  
North America ◽  
Calcareous Algae ◽  
Lower Carboniferous ◽  
North West ◽  
The North ◽  
Jurassic Rocks

Some years since Professor E. J. Garwood sent to me for examination some pieces of limestone from the Lower Carboniferous rocks in the Shap and Ravenstonedale districts of Westmorland, in which he had observed the rounded outlines of fossils with a structure which appeared to him to resemble that of Stromatopora. The rock in which the fossils were embedded was so compact and hard that they could not be extracted, and it was necessary to make sections in various directions in order to ascertain their structure, which proved to be identical with that of Solenopora, now well known as one of the calcareous Algæ. It is many years ago since this genus was recognized in the Ordovician rocks in North America, Britain, and Eussia; more recently it was found in the Silurian rocks of the Isle of Gotland, and in 1894 a species was described from the Jurassic rocks of Gloucestershire and Yorkshire. But until this fortunate discovery of its occurrence in the Lower Carboniferous by Professor Garwood, no example of the genus was known in any of the rocks between the Silurian and the Jurassic.

On Heptaphyllum, a New Genus of Carboniferous Coral

1924 ◽  
Vol 61 (9) ◽  
pp. 416-423 ◽  
Author(s):  
Arthur E. Clark
Keyword(s):  
New Genus ◽  
Growth Stages ◽  
Lower Carboniferous ◽  
North West ◽  
The North ◽  
Rugose Corals ◽  
The Subject ◽  
The Way ◽  
West Of Ireland

A few years ago Mr. Carruthers described an aberrant coral, Cryptophyllum hibernicum, from the Lower Carboniferous of Bundoran, Donegal. Cryptophyllum occurred in the Lower Calp shales, which are considered to be about at the horizon of Vaughan's C2 to S1 beds. Another aberrant genus, Heptaphyllum, also from the north-west of Ireland—Lower Carboniferous shales, Sligo—forms the subject of this paper. Cryptophyllum is remarkable, first for the manner in which the earlier major septa appear—irregularly, and nearly simultaneously, instead of regularly, and in consecutive pairs, as is typical for Rugose Corals; and also in the development of only five septa instead of the normal six in the earliest growth stages. Heptaphyllum, as its name implies, develops seven septa in the young corallum. It resembles Cryptophyllum in having an early aseptate corallum, and in the way in which the earlier septa appear.

III.—Some new Rock-building Organisms from the Lower Carboniferous Beds of Westmorland

1914 ◽  
Vol 1 (6) ◽  
pp. 265-271 ◽  
Author(s):  
E. J. Garwood
Keyword(s):  
Presidential Address ◽  
The Other ◽  
Lower Carboniferous ◽  
North West ◽  
Western Province ◽  
The North ◽  
Calcareous Alga ◽  
The Village ◽  
Important Form ◽  
North Western

In my account of the Lower Carboniferous rocks of the North-West of England, published in 1912, I figured an organism, probably the thallus of a calcareous alga, which plays an important part as a rock-builder at the base of the Seminula gregaria sub-zone in Westmorland and Lancashire. More recently, at the meeting of the British Association in Birmingham, I pointed out the need of some distinctive name for this important form, and suggested for it the generic name of ‘Ortonella’, from the village of Orton, near Tebay, in the neighbourhood of which this fossil is specially abundant. Two other structures were mentioned at the same time which occur constantly in microscopic sections of the Lower Carboniferous rocks of the North-West of England and elsewhere. The first of these was alluded to under the general descriptive term ‘festoon structure’, and the other was referred to Gurich's somewhat obscure genus Spongiottroma. In view of the zonal value of these organisms in the North-Western Province and the probability that they will be found to be widely distributed in the Lower Carboniferous rocks elsewhere, I propose here to give a somewhat fuller description of these forms than could be attempted in the limits of a presidential address.

scholarly journals Are Carboniferous coals from the Danish North Sea oil-prone?

2007 ◽  
Vol 13 ◽  
pp. 13-16 ◽  
Author(s):  
Henrik I. Petersen ◽  
Hans P. Nytoft
Keyword(s):  
Source Rock ◽  
North Sea ◽  
Upper Jurassic ◽  
Source Rocks ◽  
Lower Carboniferous ◽  
North West ◽  
The North ◽  
Single Well ◽  
The North Sea ◽  
Clay Formation

The Central Graben in the North Sea is a mature petroleum province with Upper Jurassic – lowermost Cretaceous marine shale of the Kimmeridge Clay Formation and equivalents as the principal source rock, and Upper Cretaceous chalk as the main reservoirs. However, increasing oil prices and developments in drilling technologies have made deeper plays depending on older source rocks increasingly attractive. In recent years exploration activities have therefore also been directed towards deeper clastic plays where Palaeozoic deposits may act as petroleum source rocks. Carboniferous coaly sections are the most obvious source rock candidates. The gas fields of the major gas province in the southern North Sea and North-West Europe are sourced from the thick Upper Carboniferous Coal Measures, which contain hundreds of coal seams (Drozdzewski 1993; Lokhorst 1998; Gautier 2003). North of the gas province Upper Carboni-ferous coal-bearing strata occur onshore in northern England and in Scotland, but offshore in the North Sea area they have been removed by erosion. However, Lower Carboniferous strata are present offshore and have been drilled in the Witch Ground Graben and in the north-eastern part of the Forth Approaches Basin (Fig. 1A), where most of the Lower Carbon iferous sediments are assigned to the sandstone/shale-dominated Tayport For mation and to the coal-bearing Firth Coal Formation (Bruce & Stemmerik 2003). Highly oil-prone Lower Carboniferous lacustrine oil shales occur onshore in the Midland Valley, Scotland, but they have only been drilled by a single well off shore and seem not to be regionally distributed (Parnell 1988). In the southern part of the Norwegian and UK Central Graben and in the Danish Central Graben a total of only nine wells have encountered Lower Carboniferous strata, and while they may have a widespread occurrence (Fig. 1B; Bruce & Stemmerik 2003) their distribution is poorly constrained in this area. The nearly 6000 m deep Svane-1/1A well (Fig. 1B) in the Tail End Graben encountered gas and condensate at depths of 5400–5900 m, which based on carbon isotope values may have a Carboniferous source (Ohm et al. 2006). In the light of this the source rock potential of the Lower Carboniferous coals in the Gert-2 well (Fig. 1C) has recently been assessed (Petersen & Nytoft 2007).

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