bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Carboniferous Succession in the Slaidburn District, Yorkshire
Authors: Parkinson Donald 
Published: October 2009

I. Introduction
The district which forms the subject of this paper covers an area of about 30 square miles in north-western Yorkshire, and comprises the north-eastern part of the region known as “Bolland” or “Bowland”. It lies almost entirely within the valley of the Hodder, a tributary of the Ribble, but the water-shed is crossed in the north-east, where the streams flow directly into the Ribble. The reservoir recently constructed by the Fylde Water Board is situated within the area, this part of the ground having been examined before submergence.
The area is bounded on the north and west by the grit hills of Bowland Forest, which rise to altitudes of from 1400 to 1800 feet, and on the south-east by the grits of Easington, Newton, and Waddington Fells. The steep hillsides below the grit escarpments are occupied by the Bowland Shales, whilst the lower ground is usually Carboniferous Limestone with its associated shales; the harder rock sometimes forms prominent features, of which the more notable are knolls of reef-limestone.
The stratigraphical sequence is as shown on the diagram (Pl. XXIV). It varies in detail from place to place as a result of facies changes and non-sequences, but is similar in a general way to that in the type area of Clitheroe-Pendle to the south-south-east. Figure 1 illustrates the variation in thickness and the positions of the non-sequences in different localities within the area to be described (Pendle being included for comparison).
Bolland is noted geologically by reason of the
The Evolution of the Lower Archæan Rocks in Central Sweden and their Iron, Manganese, and Sulphide Ores
Authors: Magnusson Nils H. 
Published: October 2009

The high-grade iron and manganese ores of central Sweden are well known to geologists, many of whom, however, are not aware of modern views of the relationship of the ores to the enclosing rocks and the origin of the latter. The ores are found in an ancient complex of highly altered rocks, including an extensive development of gneisses which differ so widely from their parent material that their genesis can only be elucidated by carefully tracing the sequence of metamorphic changes through a series of transitional types. In recent years much work has been done on these lower Archæan rocks, and the following account, which is mainly for non-Scandinavian readers, has been written to provide a summary of the results and to record the present state of opinion concerning the many problems encountered.
Nearly all iron ores of central Sweden belong to the leptite formation, which is the oldest formation known in Fennoscandia. It consists of volcanic rocks (lavas and tuffs) and of sediments such as slates, greywackes, and conglomerates. The volcanic rocks comprise leptites and hälleflintas, the difference between them consisting in the grade of their metamorphism, the hälleflintas having dense groundmasses, the leptites fine-grained, recrystallized groundmasses. The leptites are, in effect, more or less metamorphosed hälleflintas.
The volcanic rocks are best preserved in the westernmost part of the ore-bearing region. In the Grythytte field, for instance, N. Sundius has found extremely well-preserved hälleflint-lavas, with euhedral phenocrysts of quartz and felspar, spherulites, micro-poikilitic quartz, and fluidal and granophyric structures.
The Cairnsmore of Fleet Granite and its Metamorphic Aureole
Authors: Gardiner Charles Irving , Reynolds Sidney Hugh 
Published: October 2009

Abstract
The Cairnsmore of Fleet granite, the second largest of the four major intrusions of the Southern Uplands of Scotland, is a roughly oval mass, measuring eleven miles by seven, with the long axis trending north-east and south-west: that is, parallel to the strike of the sediments, mainly Silurian, into which it is intruded.
It is the most acid of the four intrusions and consists entirely of granite: an incomplete ring of biotite-granite, with an average specific gravity of 2·64, surrounds a larger area of biotite-muscovite-granite, with an average specific gravity of 2·61. The rocks vary very little, and the authors consider that they are the product of two successive intrusions separated by no great interval of time, the biotite-granite being the earlier.
An intrusion, about 250 yards long, of a dioritic rock bearing nickel and cobalt penetrates the sediments near the western margin of the granite and is the only mass in any way comparable with the marginal basic intrusions of the Loch Doon area.
Dykes of any kind are very scarce, not only in the granite, but in the immediately surrounding metamorphosed sediments. They are mostly quartz-biotite-hornfelses, cordierite being less plentiful than in the Loch Doon area. The metamorphism is sometimes very conspicuous, as at Knocknairling Hill near New Galloway. While at the north-eastern and south-western ends the granite cuts across the sediments, along the north-western and south-eastern margins the latter dip off the granite, which may be regarded as an intrusion essentially laccolithic in character.
The Pleistocene Geology of the Area between the Tees and the Trent
Authors: Gayner John Stansfield , Melmore Sidney 
Published: October 2009

Abstract
The Pleistocene detritus in Ryedale above Helmsley is described. A study of its distribution leads to the conclusion that at one time the surface of “Lake Pickering” stood at between 300 and 400 feet O.D. If this were so, the water must have overtopped a large part of the Howardian Hills, and evidence derived from these hills has proved this inference to be correct. Erratics of easterly derivation, now found at the same altitude on the western side of the Vale of York, have been known for a considerable time, and support the conclusion that “Lake Pickering” and “Lake Humber” formed one sheet of water. Lacustrine deposits in South Durham, of which those representing the deeper water facies extend to a height of 250 feet O.D., are described in detail.
As the result of this work, a number of conclusions have been reached, including the following: (1) a “Lake Humber”, the surface of which stood at a height of over 300 and not far short of 400 feet O.D., existed in late Glacial times; (2) even after the retreat of the Stainmore glacier from the Vale of York and the Tees basin this lake was still in existence, and its surface still at about the same level; (3) the land ice was in retreat before the North Sea ice-sheet had begun to withdraw.
The hypothesis of glacial lateral drainage, as it has been applied in the Vale of York, is briefly discussed in the light of the above conclusions.
A note is added on the character aqnd distribution of the Hessle Clay.
The Geology of Part of the Upper Luangwa Valley, North-Eastern Rhodesia
Authors: Dixey Frank 
Published: October 2009

The Luangwa Valley is a deep, broad depression that runs in a south-westerly direction down the whole length of north-eastern Rhodesia for a distance of about 400 miles (Fig. 1). Except for a short distance near the south-western end, the floor of the valley is occupied throughout by Karroo sediments, and these continue for another 400 miles in the same direction as far as the Wankie area of Southern Rhodesia. The presence of the Karroo in the Luangwa Valley is due partly to synclinal folding and partly to marginal faulting which has brought down the sediments against the margin of the crystalline plateau. Near the southern end, the western boundary fault has a throw of 5000 feet (Molyneux 1909, p. 434), and at the upper end, near Chikonta, the main eastern fault probably has a throw of about 2500 feet.
In 1907 L. A. Wallace showed that the rocks occupying the floor of the Luangwa Valley consisted of sandstones and limestones that were presumably of Karroo age. Subsequently, A. J. C. Molyneux (1909), in his account of the Karroo of Northern Rhodesia, described the sediments of the Luano Valley near the southern end of the Luangwa depression; here the beds ranged from the basal conglomerates upwards as far as the Escarpment Grits, and comprised a total thickness of about 4800 feet. They yielded fragments of fossil wood at various horizons. Fine-grained sediments of Forest Sandstone type were not seen in the Luano area nor in the Luangwa Valley (Molyneux 1909,
The pre-Karroo Landscape of the Lake Nyasa Region, and a Comparison of the Karroo Structural Directions with those of the Rift Valley
Authors: Dixey Frank 
Published: October 2009

In the course of an examination of part of the upper Luangwa Valley of north-eastern Rhodesia (Dixey 1937a) some features of unusual interest were observed in the relation of the Karroo sediments to the land surface of that time, and it was found that certain elements of that old surface still play an important part in the modern landscape. An extension of these observations into northern Nyasaland has yielded similar results, which, with those from the Luangwa Valley, are described in the following pages.
With the exception of the Livingstone Mountains (8000–9000 feet), overlooking the opposite shores of Lake Nyasa, and the neighbouring Rungwe group (10,400 feet), northern Nyasaland includes the highest and the most striking uplands throughout this part of central Africa. The nearest highlands of equal or greater height are the Mlanje Mountains (8000–10,000 feet), 400 miles to the south by east, the highlands around the northern end of Lake Tanganyika and around Lake Kivu (9000–14,000 feet) 600 miles to the north-north-west, and the highland masses of northern Tanganyika Territory (9000–19,000 feet) 600 miles to the north-north-east.
The Mlanje Mountains consist of syenite, in all probability of late Karroo or early post-Karroo age; Rungwe and the highest mountains of northern Tanganyika Territory consist of volcanic rocks, principally of Tertiary and later age; with these exceptions the highlands named, including North Nyasa, consist mainly of Muva-Ankole, Basement Complex, and other pre-Karroo formations.
The highlands of northern Nyasaland (Pl. V) comprise principally the Nyika plateau (6000–8000 feet), with five similar
The Overstep of the Sandgate Beds in the Eastern Weald
Authors: Kirkaldy John Francis 
Published: October 2009

Comparatively little work has been done on the Lower Greensand of the eastern Weald for the last fifty years, whilst the current maps of H.M. Geological Survey are based on the original survey made under Topley prior to 1875. The general succession and fauna of the beds are fairly well known in East Kent, but in East Sussex, where the beds are thin, great difficulty has been found in the past in subdividing them and correlating them with the lithological subdivisions recognizable in other parts of the Weald.
Detailed mapping of the outcrop has, however, shown that in the extreme east of Sussex the Sandgate Beds overstep the Hythe Beds to rest on the Weald Clay. A similar overstep is traceable in the Boulonnais and in the boreholes of the East Kent coalfield.
The only literature relating to the Lower Greensand of Sussex is to be found in the pioneer accounts of Martin, Mantell, and Fitton, and in the memoirs of H.M. Geological Survey. In Topley's classic memoir (1875, p. 126) the Lower Greensand is described as retaining its usual lithological units to beyond Henfield, but farther east, owing to the disappearance of the distinctive stone bands, it was found to be incapable of subdivision. At a later date, part of the area was resurveyed by Lamplugh (Reid 1903), whilst the country farther east was redescribed, but not remapped, by Osborne White (1924, 1926), who also experienced difficulty in the correlation of the beds of the Lewes area with the
The Geology of the Solwezi District, Northern Rhodesia
Authors: Hatfield Willis Charles 
Published: October 2009

The Solwezi district lies on the southern side of the Congo-Zambezi divide along the Rhodesian-Belgian Congo border, approximately 100 miles west of N'Changa. It comprises nearly 450 square miles and forms part of the great Central African Plateau. It is a previously unmapped portion of the Northern Rhodesian copper belt, of which the climate, vegetation, and general features are adequately described in many of the works referred to on p. 152. The district is named after the Government post at Solwezi, the officials at which generously gave assistance at numerous times during my investigation of the area.
I am greatly indebted to Dr. J. A. Bancroft, who directed the field work in 1929, and to Dr. C. P. Berkey and Professor R. J. Colony, who guided the laboratory work at Columbia University.
The Solwezi district forms a small part of an uplifted peneplain now in the youthful stage of dissection by the headwaters of small tributaries of a major branch of the Zambezi river. The average elevation is approximately 4500 feet. Numerous low ridges and scarps and a few isolated hills interrupt an otherwise gently rolling surface, and the present physical features strikingly reflect the character of the underlying rocks.
The rocks, a continuation of the complexly folded and faulted Pre-Cambrian formations of Katanga to the north, range from the Basement Series through the Mine Series and part of the Kundelungu, and in this paper are divided into five natural groups, as was done in the field for convenience in mapping
The Geological Basis of the Present Search for Oil in Great Britain by the D'Arcy Exploration Company, Ltd.
Authors: Lees George Martin , Cox Percy Thomas 
Published: October 2009

Seepages of oil at the surface or in coal mines have been known in Great Britain for several centuries. Records of the use of oil from the Coalport seepages date from 1684. James Young in 1847 extracted wax, burning oil, and lubricating oil from a crude oil obtained in the Biddings colliery, near Alfreton in Derbyshire. In 1902, some boring was carried out in the Sussex Weald, stimulated by the accidental discovery of natural gas at Heathfield, but this enterprise was soon abandoned.
In 1918, a serious search for oil was made under the pressure of war-time conditions, and Messrs. S. Pearson & Son, Limited, between 1918 and 1921, under contract for H.M. Government, drilled 11 test-wells: seven in Derbyshire, two in Staffordshire, and two in Scotland. In every case the objective was an oil accumulation in Carboniferous beds. A small production was obtained from their first well, Hardstoft No. 1 in Derbyshire, and showings of oil were struck elsewhere, notably in the D'Arcy well in Scotland. Although the results up to that time may not have been conclusive, they were not considered sufficiently encouraging to justify further Government expenditure, and operations were suspended. Two wells were drilled later (1924–26) on the Hardstoft structure on the initiative of the Duke of Devonshire, owner of the property, but neither obtained any oil-production.
Other attempts during the last 20 years to find oil by drilling have been those at Kelham, near the site of a coal exploration borehole, which found a show
The Coal Measures of Bristol and Somerset
Authors: Moore Leslie Rowsell , Trueman Arthur E. 
Published: October 2009

The Coal Measures of Bristol and Somerset are in some ways less completely known than those of most other English coalfields. This is partly due to the fact that the Coal Measures are to a great extent concealed under newer rocks, while the interpretation of the sequence has been made still more difficult by the complexity of the structure, especially in those areas where the lowest part of the sequence is exposed. Maps of the area on the one-inch scale were published in 1845, and some revision has been made since; an account of the sequence and structure was prepared by Prestwich in 1871, and a memoir by H. B. Woodward was published in 1876. Since that time sections of colliery shafts have been issued by the Geological Survey (sheets 11, 48-52). Other works on the area are referred to incidentally below.
The general lithological sequence has been recognized for many years, but the correlation of the various parts of the coalfield has been largely a matter of speculation: there has been little palæontological evidence on which even a tentative correlation could be based.
Several workers have, however, made important contributions to the palæontology of the coalfield. The rich floras of the upper part of the Coal Measures, long famous in the Radstock district, were investigated by Kidston (1887) and more recently by Dr. R. Crookall (1925, 1929). The lower part of the sequence, which is generally less fossiliferous, received less attention, and its floras are very incompletely known; from
The Tectonic Problems of an Area of Salopian Rocks in North-Western Denbighshire
Authors: Boswell Percy George Hamnall 
Published: October 2009

The area which forms the subject of this communication comprises nearly 300 square miles of country in north-western Denbighshire; its boundaries are the Gonway valley on the west, the Irish Sea on the north, the Vale of Clwyd on the east, and the road from Bettws-y-coed to Cerrig-y-druidion and Derwen on the south. This area is occupied by Salopian rocks, and its interesting tectonic features have engaged my attention for several years. Certain parts of the work on the district have already been published (Boswell 1926, 1928A, B, 1930, 1932; Boswell and Double 1934), and an account of the tectonic features was to have followed the completion of the re-survey of the area on the six-inch scale, a task that has been delayed because of the limited opportunities now available to me for field-work.
Recently, however, certain of the disturbed beds in the area have been interpreted as the result of slumping movement (contemporaneous submarine sliding), and since this explanation differs from the interpretation that I should offer, it seems desirable that some details supplementary to the earlier accounts should now be put on record. Certain of the tectonic phenomena about to be described anoear to be novel.
One of the most complete successions of graptolite-bearing Salopian rocks is displayed in the region. Moreover, the area is sufficiently large to permit many interesting lateral changes in facies to be traced. For the most part, the succession and geographical distribution of these rocks have been described in earlier papers, but the
Rock Succession and Structure in South Cornwall: a Revision. With Notes on the Central European Facies and Variscan Folding there present
Authors: Hendriks Eileen M. Lind 
Published: October 2009

The area dealt with in this paper is the coast of South Cornwall from Porthleven in Mount's Bay to Pentewan in Mevagissey Bay. It is separated by the Carrick Roads and tributary creeks into two parts, Meneage and the Roseland-Gorran country. The similarity of the rocks and problems in the two areas is recognized in the memoirs of H.M. Geological Survey (Flett and Hill 1912; Hill and MacAlister 1906; Reid 1907; Reid and Scrivenor 1906), but no detailed correlation based on local developments has been made, and the stratigraphical terms in use (“Mylor,” “Falmouth,” “Portscatho,” “Veryan,” “Manaccan” and “Grampound”) have never been satisfactorily defined, so that the geological history of Cornwall is still unexplained.
The rock succession of South Cornwall begins with the altered rocks of two peninsulas (the Lizard and Dodman), of unknown age, related to one another and to the Start in South Devon by their rock types and by certain peculiar features in their boundary lines. The Lizard differs from the other two in the presence of an intrusive complex, also of unknown age, of serpentine-gabbro and granite-gneiss, described in 1912 by Sir John Flett, who regarded the serpentine as injection-foliated, and the Lizard boundary features as compatible with both dislocation and intrusion (Flett and Hill 1912, pp. 213–6, 242). In 1896, Professor Bonney had pointed to Kiberick valley, near Veryan, as a locality likely to afford crucial evidence of the age of the Lizard serpentine (1896, p. 48), and he had previously (1877)
Observation on the Geology of Northern Central Africa
Authors: Sandford Kenneth Stuart 
Published: October 2009

The object of this lecture is to sketch the geological history of a remote continental region, much of which remains to be surveyed, between the Belgian Congo and Cyrenaica, the Nile and the French Sahara and Soudan. Only incidental reference is made to Egypt, East and South Africa, and territories where British official surveys are established. An effort is also made to review recent Belgian, French, and Italian work in this region. I am especially indebted to Mr. H. B. Maufe, who read the text and gave much valuable advice, to M. Blondel, Director of the Bureau d'Études géologiques et Minières coloniales, Paris, and to M. T. Monod, of the Muséum d'histoire naturelle, Paris, for their unstinted help. My thanks are due also to M. R. Perret for the photograph reproduced as Plate XXXII, to MM. Perret and J. Bourcart for permission to reproduce Figure 2, and to my wife for the photograph of Plate XXXIII and for much help in preparing the text and bibliography.
This attempt to visualize the geology of the region as a whole is based on my field work in the critical central area. The whole of the well-known and broad coastal and marginal lands are omitted from consideration : they can be studied in official publications and in the works of Krenkel (1925–34) and other authors. Reference is made also to the Congo basin-Zambesi watershed.
These rocks may be divided into an Archaean basement complex and a series of altered, often highly folded, sediments
The Age of the Mountains of Snowdonia
Authors: Greenly Edward 
Published: October 2009

The Development of Opinion on the Problem.
—Half a century ago, it seems to have been widely held that the mountains of North Wales were, as mountains, very ancient; much older, it was remarked, than some which are loftier and more famous. Yet by 1867–1870 it had come to be generally recognized that the mountains of the Inner Hebrides (which are very nearly as high) are, as mountains, of Tertiary age (Geikie 1897, pp. 114–5). Why did not this arouse speculation with regard to the mountains of Wales?

Some ten years later it was urged by Goodchild (1880; repeated, more fully, in 1888 and 1889) that the mountains of Lakeland had been sculptured out of a high plateau which was a sub-Cretaceous floor, so that, as mountains, they must be of Tertiary age.
About the same time, Ramsay (1881, p. 319) expressed an opinion which approached Goodchild's somewhat nearly: “During the deposition of the chalk, there is no proof that the higher parts of Wales were altogether submerged, but rather the opposite.” He does not (so far as I know) specify the grounds for this “opposite”, and seems indeed not to have thorough-going confidence in it, for he says on p. 320: “It thus appears that since the beginning of the Permian epoch, the higher ground of Wales has formed land well raised above the level of the sea, and even if there be some doubt about this while the chalk was being deposited, that must have formed merely an episode