bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Origin of the Etruria Marl
Authors: Robertson Thomas 
Published: October 2009

It has long been known that there lies immediately above the main productive Coal Measures of the Midlands a peculiar group of variegated clays. These beds are known by differ- ent names in the different coalfields, but the best-known term is that of Etruria Marl, first used by Dr. W. Gibson in his elucidation of the sequence in the Upper Coal Measures of North Staffordshire.
The position of this group in the Coal Measure sequence is as follows:—

A consideration of the nature and distribution of the deposits of Etruria Marl type in the Midlands shows

1.
That they are similar in macroscopic and microscopic character and in chemical composition to deposits undoubtedly formed by the decomposition of the basaltic rocks of the Midlands and of many other districts.

2.
That they contain, in the vicinity of the Midland basalts, actual fragments of decomposed basalt.

3.
That they were deposited at times during which we have proof of extensive denudation of basic volcanic rocks in the Midlands, and in the areas in which we have proof that the products of this denudation were deposited.

4.
That no known occurrence of earlier rocks is competent to produce a deposit corresponding in age, character, quantity and distribution to the Etruria Marl of the Midlands.

These facts appear to admit of no escape from the conclusion that the Etruria Marl was produced by the decomposition and denudation of the Midland Basalts in
The Geology of North-Eastern British Somaliland
Authors: Brown Charles Barrington 
Published: October 2009

This paper deals with a strip of country lying along the 49th meridian east of Greenwich from the coast to about 80 miles inland, and with a belt 50 miles long running westwards of that meridian between latitudes 11° 00′ and 11° 08′. The political boundary between British and Italian Somaliland coincides with this meridian.
I was fortunate in being provided with the topographical map, contoured at 250-foot intervals, which had recently been made by the officers of the Anglo-Italian Boundary Commission. Part of this was enlarged to the scale of 1 inch to a mile, and with it I mapped geologically a considerable area.
North-eastern Somaliland has been visited previously by geologists on two occasions. R. A. Farquharson (1924), the Government Geologist of the Protectorate, made a reconnaissance from Las Khorai along the foot of the Al Hills for some 25 miles, and thence to Bunda Ziada, from whence he returned by a more northerly route. Prof. G. Stefanini (1925) journeyed southwards in 1924 from Bosaso on the coast, in Italian territory, and crossed into British Somaliland at Hegligab: thence he passed through Buran to the Nogal Valley. The greater part of the district I mapped had, therefore, been unvisited hitherto.
II. Topography.
The political boundary crosses four types of surface:―
(1) The Nogal Valley and Sorl Haud: drainage east-ward.
(2) The Hormo Plain: drainage eastward.
(3) The A1 hills: drainage south to south-eastward on one flank, and northward on the other.
(4) The coastal region: drainage northward.
(1)
Additional Fossils from the Cambrian Rocks of Comley, Shropshire
Authors: Cobbold Edgar Sterling 
Published: October 2009

During the last 20 years a good many additions have been made to my collection from the Cambrian rocks of Comley. Some of these specimens indicate species new to the locality; others throw additional light on those previously described.

An attempt is also made in this paper to clear up a number of doubtful generic references that have appeared in my previous communications. Particularly is this the case with those species that were formerly referred by me to
Micmacca
Matthew and
Anomocare
Angelin. Matthew's genus is certainly present, but some of the specimens must be put under
Strenuella
. Angelin's genus is not represented, and the forms so designated seem to come under
Protolenus
and
Strenuella
.

Prof. P. E. Raymond (1913, p. 102) defines the family as follows:—
‘Hypoparia of small size, cephalon and pygidium subequal, free cheeks absent from the dorsal side, thorax of three segments; pygidium annulated or smooth. Lower and Middle Cambrian. Northern Europe and Eastern North America.’

He includes the following genera in the family:—
Eodiscus
Matthew, type species
E. schucherti
Matthew;
Goniodiscus
Raymond, type species
Microdiscus lobatus
Hall;
Weymouthia
Raymond, type species
Agnostics nobilis
Ford.

Unfortunately,
Goniodiscus
is pre-occupied, having been used by Müller and Troschel in 1842 for an asteroid. I do not propose any new generic name to replace
Goniodiscus
, for, on analysis of the published figures of the species of the Eodiscidae, I find that in respect of Raymond's first distinction, namely, the relative lengths of the glabellae, the two groups seriously overlap, and
The Stratigraphical Distribution of the Cornbrash : II. The North-Eastern Area
Authors: Douglas James Archibald , Arkell William Joscelyn 
Published: October 2009

I. I
ntroduction

I
n
a previous communication to the Society (
Douglas & Arkell, Part I, 1928
) we gave a detailed account of the stratigraphical distribution of the Cornbrash in the South-West of England between Oxford and the Dorset coast, describing the more important features of the faunal sequence and giving our reasons for amending the list of brachiopod zones propounded by the late
S. S. Buckman (1927, p. 10)
.

The present paper deals mainly with that part of the Cornbrash outcrop which lies between Oxford and the Humber, running through the counties of Oxfordshire, Buckinghamshire, Bedfordshire, Northamptonshire, and Lincolnshire. Preliminary observations on the outcrop in Yorkshire are also included, but the detailed investigation of that county has not yet been completed.
Many of the conclusions arrived at during our study of the South-Western area have been strengthened or confirmed by discoveries made when following the outcrop farther north, and many new facts have come to light which show that our criticism of Buckman's clinal diagram (1927, p. 12), in which he sought to prove extensive penecontemporaneous erosion in the Cornbrash, was fully justified. As before, we have confined our attention chiefly to the brachiopod sequence, but it is hoped that the numerous ammonites collected will be dealt with at some future date.
It may be recalled that the exact stratigraphical position of two of the suggested brachiopod zones—those of Tegulithyris bentleyi and Obovothyris stiltonensis, yet remained to be proved. The first-named (Zone 11) was placed by Buckman at the summit of
An Ordovician Grit from Anglesey, with its bearing on Palæogeography and on the Tectonics of the Mona Complex
Authors: Edward Greenly , Boswell Percy George Hamnall 
Published: October 2009

I. I
ntroductory

S
ome
15 or 20 years ago, the rocks and slides collected by-Blake and Callaway were purchased by the Geological Survey. The Anglesey slides were put into the hands of one of us (E. G.), and many of them were used for the Memoir upon Anglesey. Later on, both collections were gone through systematically, partly for further description, but partly because, by means of the 6-inch geological maps, it had become possible often to state the localities with much greater precision.

One of the Blake slides (J.F.B. 315 = E. 10914) is an Ordovician grit. It is labelled ‘ South of Holland Arms ’, and while possibly from the floor of the steep lane about 100 yards south of the Inn, is more likely to be from Glanmorfa lane—a quarry in the Ordovician strip which, running for a mile from Berw-uchaf to Tai-hirion, may conveniently be termed the Berw strip.
It was found to be surprisingly rich in heavy minerals, and was therefore sent to the other author (P. G. H. B.). The Geological Survey also very kindly had a piece cut off Blake's specimen in order that the heavy minerals might be separated. In March, 1931, we re-examined, together, all the exposures of the Berw grits, and collected specimens for slicing and separation.
These Ordovician rocks are briefly described by Ramsay.In the Anglesey Memoir they are considered, under the subtitle of ‘ The Strips along the Berw Faults ’, on pp.
Petrology of the Volcanic Fields East and South-East of Ruwenzori, Uganda
Authors: Holmes Arthur , Harwood Henry Francis 
Published: October 2009

I. G
eneral
D
escription of the
V
olcanic
A
reas

U
ntil
1891 the possibility was entertained that Ruwenzori, like the other high mountains of Central Africa, might be of volcanic origin. As a result of his explorations during that year,
Dr. F. Stuhlmann (1894)
showed that this preliminary suggestion was without foundation, adding that no signs of volcanic activity had been detected in the regions traversed. In 1894, however, G. F. Scott Elliot recognized three well-marked volcanic belts in the adjoining country east and southeast of Ruwenzori (
Elliot & Gregory, 1895, p. 674
;
Elliot, 1896, p. 168
). He described the bedded tuffs, craters, and crater-lakes of Toro (fig. 1) as occurring in the Vijonga area (Lake Kijongo), north-west of Fort Portal; the Butanuka or Kyatwa area, south of Fort Portal, locally forming the boundary of the low Toro plains to the east; and the Katwe and Kaihura Straits area (north-west of the Kazinga Channel between Lakes George and Edward).

It is remarkable that Stanley failed to recognize the volcanic origin of the famous salt-lake of the Katwe crater. He visited the locality in 1889 and commented on the deep depression and the salinity of the lake, and even recorded the occurrence of a spring of sulphurous water.
Scott Elliot also indicated that Karimi Hill, south-west of Ruwenzori (now in Belgian territory), might be of volcanic origin, and suggested that the different belts of cones and craters were alined on fissures radiating outwards from the uplifted massif of Ruwenzori. The nature of Karimi Hill
The Geology of some Salt-Plugs in Laristan, Southern Persia
Authors: Harrison John Vernon 
Published: October 2009

Salt-Plugs occurring in a bare land such as Laristan are intriguing, on account of their fantastic shapes, their queer colouring, and their rock-assemblages. Their profusion here and in only a few other regions in the world awakes interest regarding causal forces, as also the desire to make comparisons.
During a reconnaissance in the season 1928–29 I had the opportunity, with A. H. Taitt, to visit or view thirty-three different salt-plugs. Although the needs of survey prevented us from making a detailed study of any of the occurrences, notes and specimens were collected in sufficient quantities to yield a considerable amount of new information, which is set forth below.
The extrusive salt has come to the surface at different periods from Oligocene to Pliocene, has formed hills and salt-gypsum ‘glaciers’, and has left after erosion great corries in the limestone ‘whaleback’ mountains of the region. It has penetrated the folds irregularly, so that the salt-masses show no recognizable order of distribution within the zone where they occur, an area determined by the front of the South Persian nappes. It is suggested that they have originated through tangential pressure acting on a series of beds which extends at least as low as the Ordovician in places, is up to 25,000 feet thick, and is underlaid by salt and gypsum of Cambrian or possibly pre-Cambrian Age.
A. T. Wilson (now Sir Arnold) (3), G. E. Pilgrim (2, 9, 11), R. K. Richardson (15, 25), K. Krejci (20), G. M. Lees (21, 24, 27),
The Iron-Ore Oolites and Pisolites of North Wales
Authors: Pulfrey William 
Published: October 2009

I. Introduction and History of Previous Research
The oolitic iron ores of Anglesey, Carnarvonshire, and Merionethshire in North Wales (see fig. 1) have received attention from numerous authors since the middle of the nineteenth century. These ores, of variable nature and age, consist largely of chlorite with or without clastic constituents, and locally peculiar varieties contain haematite, pyrite, etc., usually associated with chlorite. They generally contain abundant nodules bearing sponge spicules.

The literature of the Welsh oolites is extensive and has been clearly summarized by Sherlock and Cantrill (1920) in a special report of the Geological Survey on iron ores. Two years previous to the publication of this report, Sherlock (1918) had described the pyritic ores of Trefriw, and had concluded that they are probably a highly metamorphosed pisolitic iron ore of Nemagraptus gracilis age. The Geological Survey Memoir on Anglesey (Greenly, 1919) gave an account of the oolitic iron ores of the island. Greenly distinguished three types of ore—feebly oolitic siderite rocks, ferrified grits, and ‘heavy oolites’, and proved most of the ores to be of
Nemagraptus gracilis
age.

A further special report of the Geological Survey, by A. F. Hallimond (1925), dealt with the nature and origin of the oolitic ironstones of Great Britain, including an account of some Welsh ironstones. Hallimond proved the almost universal presence in the English ores of chlorites allied to chamosite, but he believed that other chlorites would be found in the Welsh ores, owing to some degree of metamorphism. He concluded that
The Upper Devonian Rocks of The Chudleigh Area, South Devon
Authors: Anniss Leslie George 
Published: October 2009

I. Introduction
The Upper Devonian rocks under consideration occupy a small portion of the area of the 1-inch geological map (Sheet 339). They occur as small faulted inliers on the north-eastern side of the Bovey basin in a region otherwise occupied by Culm overlain by Permian and Cretaceous strata. The main (Chudleigh) outcrop, which is a mile across at its widest part, extends from the neighbourhood of Harcombe to Chudleigh Rocks—a distance of
about 3½ miles. East of this outcrop, and on the same latitude as Chudleigh, is the small triangular patch of Lower Dunscombe, and farther south lies the much larger but partially concealed Ugbrooke-Well inlier, which appears on the map as three detached outcrops. The nearest edge of the Dartmoor granite
lies about 2½ miles to the west. The Devonian inliers include the upper part of the Massive Limestone of South Devon thrust over thinly bedded limestones and shales. The Massive Limestone is here shown to be Lower Frasnian and the thinly bedded limestones and shales Upper Frasnian and Famennian respectively. The Kate Brook, the main stream in the area, has cut its valley along the main outcrop of the Famennian shales. The lowest part of the valley lies below the 100-foot contour. The Massive Limestone flanks the depression on the east, rising to 300 or 400 feet; the surrounding Culm forms undulating ground 400 to 500 feet high. The Permian with its Cretaceous capping rises to 700 feet in the north-east.
My thanks are due to Lord
The Carnmenellis Granite: Its Petrology, Metamorphism and Tectonics
Authors: Ghosh P. K. 
Published: October 2009

I. Introduction
The Carnmenellis granite and its metamorphic aureole were mapped, in 1839, by de la Beche. The area has since been re-surveyed by the Geological Survey and the results recorded in the one-inch maps, nos. 352 and 359 (New Series) and in the Survey Memoir on the Falmouth and Camborne district (Hill & MacAlister, 1906). The granite is an important unit in the chain of post-Carboniferous granite intrusions forming the backbone of the peninsula of Cornwall and Devon.
The consanguinity of these intrusions has long been known, but the recognition of the composite character of individual intrusions is comparatively recent. Intrusive relationship between major composite masses was observed on Dartmoor by the members of the Geological Survey (Reid & others, 1912), Brammall (1923), and Osman (1928), and on Bodmin Moor by myself (1927). Intrusion sequences are discussed by Brammall (1923 & 1932) and Osman (1928).
Important petrological contrasts between the Devonian and the Cornish granites were pointed out by Flett and Dewey (Reid & others, 1912), and problems of variation within individual complexes have since been made the basis of detailed study by Osman with special reference to the Dartmoor and Scilly Isles masses, by Richardson (1923) dealing with the St. Austell granite, and by myself in a paper on the Bodmin Moor granite (1927), and the Carnmenellis granite, the subject of the present contribution. I would add that, subsequent to the presentation of the paper to the Society, I have had the advantage of re-examining my analytical data
The Borrowdale Volcanic Series and Associated Rocks in the Country Between Long Sleddale and Shap
Authors: Mitchell George Hoole 
Published: October 2009

I. Introduction
A remote and little frequented group of fells lying some ten miles to the north of Kendal in the eastern part of the Lake District forms the easterly portion of the mountainous country centred on High Street (Mitchell, 1931). The area is traversed by the main watershed of the Lake District extending from Harter Fell by way of Gatesgarth Pass, Tarn Crag, and Grey Crag to Shap summit on the L.M.S. Railway. The highest ground is in the west, where High Street and Harter Fell are more than 2500 feet in altitude. Eastwards the level falls steadily until the escarpment of the Carboniferous Limestone is reached between Shap summit and Bampton. Much of the fell is smooth in outline; but long stretches of craggy ground break the monotonous grass-covered slopes. This is specially noticeable in the valleys, for most of them exhibit signs of severe glaciation, which has resulted in those steep cliffs and bare rock faces which contribute in no small degree to the boldness of the scenery. In the Lowther valley near Shap, the ground is thickly smothered by glacial drift, which forms long mounds and hummocks, effectively masking the solid rocks over large areas.
To the south of the watershed, a number of streams flow in a south-south-easterly direction. Of these, the River Sprint in its upper reaches is formed by the junction of several small gills—Wren Gill is the largest—that have their sources on the southern side of Gatesgarth Pass. Almost at once the
The Age and Origin of the Lower Rhône
Authors: Oldham Richard Dixon 
Published: October 2009

I. Introductory
In a previous communication to this Society it was shown that the region of the lower Rhône, bordering the main stream from Beaucaire and Tarascon to the sea, which has been currently accepted as a typical delta, was, genetically, of very different origin, the deltaic character having been impressed on it at a late period in the development of the river.
The stratigraphy of the alluvium is such that it can only be accounted for by a barrier having formerly existed beyond the sea-coast of the present day, and the Rhône having been compelled to flow westwards to the neighbourhood of Cette, or possibly still farther, before it found an outlet to the sea. Across this barrier a passage was opened, and became the main channel by which the river found access to the Mediterranean, but this occurred at a period which, geologically speaking, is extremely recent, though anterior to the first appearance of Roman power in this region.
A similar conclusion may be drawn from a study of the two branches of the Rhône. The eastern branch is not only the larger but is also materially shorter in length, measured from the bifurcation to the sea, and this condition is necessarily unstable; the greater volume and the steeper gradient would give greater power to the eastern channel, which must ultimately lead to a capture of the whole of the discharge of the river and to the disappearance of the western branch. Though the bifurcation must be regarded
The Downtonian and Dittonian Strata of Great Britain and North-Western Europe
Authors: King William Wickham 
Published: October 2009

I. Introduction
The determination of a Siluro-Devonian boundary in Great Britain and north-western Europe has been dealt with by Barrels, Pruvost, and Dubois (1920), Stamp (1923), and Robertson (1928). My own investigation has been based in part on an application of the principles relating to deposition of sediments set out by Watts (1911), and more recently by Marr (1929). It has been shown (King, 1925) that the Down-Ionian and Dittonian strata of the West Midlands of England are mainly marls, belonging to one ldmud belt”, and laid down in epi-continental marine waters of moderate depth; and that they are a conformable sequence of beds transitional from the Upper Ludlow.
The discovery, described later, of a shell fauna, abundant in individuals but sparse in genera and species, reaching nearly to the top of the Downtonian, is of some utility if considered in connexion with the Merostomata and fishes, and with the physiographical conditions under which these sediments with a “red fades” were laid down in north-western Europe. I have, therefore, investigated this region, in part personally and in part by making use of the work of others, so as to trace the “variable”, and “mud,” and “organic” belts (not oozes) laid down in the Siluro-Devonian period on this continental shelf, the continuation of a north-western land which at first encroached on the sea to the south-east, but in Devonian times receded again. The following divisions and stages are now adopted for the West Midlands, including the Black Mountains, where the Downtonian
The Eastern end of the Newry Igneous Complex
Authors: Livesey Reynolds Doris 
Published: October 2009

I. Introduction
The Newry Igneous Complex, generally known as the Newry granite, extends from Slieve Croob in County Down, where it attains its greatest height, south-westward past Newry into County Armagh. A general account of the “granite” was given by J. E. Richey and H. H. Thomas in their recent description of the Tertiary Ring Complex of Slieve Gullion. As pointed out by Richey, it has an elongate outcrop with dimensions of roughly 26 by 6 miles, extending in a direction E. 35° N. to W. 35° S. parallel to the prevalent strike of the Silurian rocks, and can be assigned to the Old Red Sandstone period of activity.
The eastern end of the mass is now definitely dated by the fact that on Seeconnell it is cut by hornblende-lamprophyres (spessartites), similar to the uncrushed hornblendic types in the Ards Peninsula and there found to belong to the Caledonian period of activity, but to be post-Caledonian folding in age. This evidence, in conjunction with the absence of signs of crushing in the eastern end of the mass, fixes the age within narrow limits.
The present paper forms part of a detailed investigation of the area, and deals with the eastern end of the complex as far westward as Slievenaboley and southward to Lough Island Reavy, the region described being about 21 square miles. This small area is so crowded with interest in regard both to variety of rock-types and evidence of hybridization and ultrametamorphism, that it is considered to merit