bluuebunny/crossref_metadata_2025 huggingface dataset:
The Geology of the N'Changa District, Northern Rhodesia
Authors: Jackson Gerald Christopher Arden
Published: October 2009

I. I
ntroduction

T
his
paper presents a brief account of the general geology and petrology of a previously unmapped portion of the Northern Rhodesian copper belt, and covers approximately 800 square miles of territory. The map-area forms a portion of the Rhodesian Congo Border Concession now being explored by the Rhokana Corporation, Ltd. The area is bounded on the south by the 13th parallel of south latitude, on the east by the boundary between the Rhodesian Congo Border and the N'Kana Concessions, and on the west by the Lufwanyama River. Its northern boundary lies approximately 6 miles north of the Kafue River near N'Changa, and 8 miles south of the Belgian Congo border.

The district is in the heart of the Northern Rhodesian copper belt, and includes the N'Changa Copper Mines Ltd. Concession and its extensions; it lies in close proximity to the other principal copper deposits of Northern Rhodesia and the Katanga.

Within the last few years, Northern Rhodesia has attracted wide interest by virtue of its recently discovered copper deposits, which in tonnage and tenor of ore now rank amongst the foremost of the world. Lying within this region, the N'Changa district, in respect of both geology and mineralization, is typical of the Northern Rhodesian copper belt, and contains, perhaps, a wider range of rock types and a greater abundance of natural exposures than is usual in neighbouring districts. Consequently, the results of the studies described in this paper may assist in the elucidation of the broader problems of
The British Carboniferous Reticulate Spiriferidæ
Authors: George Thomas Neville
Published: October 2009

I. I
ntroduction

I
n
this paper are considered those members of the Spiriferidae which are commonly characterized by the presence of a clath-rate or spinous ornament, and which have usually been referred to the genus
Reticularia
M'Coy. Certain similar forms have been considered in a previous paper (
George, 1931
), but although in the past these have been classed with
Reticularia
(
Waagen, 1883, p. 497
), they are very different from that genus in both external and internal structure (
George, 1931, p. 41
).

Forms which have been included in
Reticularia
are recorded from Permian, Upper Carboniferous, and Devonian rocks of other countries, but as these are very rare in, if not entirely absent from, the rocks of Great Britain, only those of Lower Carboniferous age are here considered. No attempt at an exhaustive study of the British species has been contemplated ; only the more common forms, or those demonstrating certain interesting peculiarities, are described.

While many of the specimens examined were of my own collecting, I am under considerable obligation to numerous people for permission to examine specimens committed to their care, or for the loan of specimens from private collections; some were so kind as to permit me to determine the internal features by polishing and making serial sections. For such facilities, I wish to thank Dr. R. G. Absalom (Kelvingrove Museum); Mr. G. B. Alexander; Dr. F. A. Bather, Dr. W. D. Lang, and Miss H. M. Muir-Wood (British Museum, Natural History); Dr. E. D. Currie (Hunterian Museum); Prof. E.
The Geology of the Western Macdonnell Ranges, Central Australia
Authors: Madigan Cecil Thomas
Published: October 2009

I. I
ntroduction

T
he
literature on the geology of Central Australia is now becoming somewhat voluminous. Owing to the vastness of this largely desert area, the sparseness of settlement, which is almost wholly confined to the neighbourhood of the overland telegraph line, and the cost and difficulty of travel in a land where waters are few and far between and petrol only available if sent out by camel, the geological work has been in the nature of rapid route reconnaissances in scattered directions.

Although the chief ore deposits are in the eastern MacDonnell Ranges, very little has been done in that area, while the western ranges, though quite devoid of any mineral wealth, have received a relatively large amount of attention geologically. The reason for this is that on the western side of the telegraph line the geological structures show comparative simplicity, while to the east there has been much more complex movement, the formations occurring in jumbled hills and ranges in such confusion as only closely detailed mapping could unravel. The key to the geology of the whole area lies in the west.

I first visited the western MacDonnell Ranges in company with Sir Douglas Mawson in 1927. A hurried motor journey was made to near Glen Helen Station, 90 miles west of Alice Springs, to inspect a deposit of saltpetre in limestone caves Only five days were spent in the field, three of them in travel ling, and there was little time for geological work apart from examining the
The Permian Lavas of Devon
Authors: Tidmarsh Wilfred George
Published: October 2009

I. I
ntroduction

T
he
rocks to be described comprise the relics of a suite of lavas forming two main groups of exposures : (i) the Exeter lavas, constituting a zone of outcrops north of Dartmoor, and (ii) lavas south of Dartmoor occurring near Kingsbridge and in the Maker peninsula south-west of Plymouth. These rocks present features of special interest as being the latest surface manifestations of the Dartmoor cycle of igneous activity, and are products of a later stage of magmatic differentiation than any other known rocks of the region.

All the occurrences have been previously recorded and, in part, described, but the probable modes of origin have not hitherto been discussed. The present investigation was, therefore, directed to the study of the suite as a whole in the light of recent petrological progress, the object being to determine the precise character and sequence in time of the Devon lavas and to discuss the genetic relationship with the igneous rocks in the Devon sub-province.

(a) Distribution of the Lavas

Geographically, the lavas occur in five groups : (i) immediately to the south-west of Exeter, (ii) in the valleys of the Exe, Culm, and Clyst, (iii) in the Crediton valley, (iv) west of Tiverton, and (v) to the south of Dartmoor.

With the exception of the rocks in groups (ii) and (v), the lavas occur generally at or near the boundary between the Culm Measures and the Permian. Lavas of group (ii) appear to lie higher in the succession and, with minor
The Tertiary Ring Complex of Slieve Gullion (Ireland), with Petrological Notes by Herbert Henry Thomas
Authors: Richey James Ernest
Published: October 2009

I. I
ntroduction

T
he
Tertiary plutonic rocks of north-eastern Ireland are confined to two main areas—the Mourne Mountains in Co. Down and the mountainous tract of country extending from the Carlingford peninsula, in Louth, north-westwards to beyond Slieve Gullion, in Co. Armagh. They are intruded into the middle of the well-known belt of Ordovician and Silurian strata which continues north-eastwards across the Irish Sea to form the Southern Uplands of Scotland. Near Carlingford, the Carboniferous Limestone also is cut by the plutonic rocks, while the country rocks immediately around Slieve Gullion consist of the Caledonian (or Lower Old Red Sandstone) granite of Newry (fig. 1).

The Tertiary age of the plutonic rocks has been for many years accepted, on account of their petrological similarity to those intruded into the Tertiary basalt lavas in western Scotland. In Ireland, the basalts overlie the Antrim chalk and transgress southwards across the Carboniferous, Silurian, and Ordovician sediments of Armagh and Down. Remnants of the basalts are now known to occur still farther south, within the Slieve Gullion and Carlingford area. These, as is shown below, are earlier than the Slieve Gullion plutonic rocks, and direct evidence of the Tertiary date of the intrusive complexes is thus forthcoming.

reservoir was formed by subsidence rather than by melting. Not improbably the western portion of the Newry granite itself occupies the space left by a cauldron subsidence of Lower Old Red Sandstone date. If at some depth in the crust there lay a subsided mass of country rock,
Upper Devonian Fishes from New South Wales
Authors: Hills Edwin Sherbon
Published: October 2009

I. I
introduction

S
ome
years ago, the Geological Survey of New South Wales sent a small collection of Devonian fishes from that State to Sir Arthur Smith Woodward, who, however, beyond exhibiting certain specimens at a meeting of the Geological Society in 1916, did not deal more fully with them, and I am greatly indebted to him both for permission to describe the remains, and for discussion and revision of the manuscript. The Under-Secretary for Mines in Sydney sanctioned the undertaking of the descriptions, and I was especially fortunate in that Prof. Stensiö of Stockholm was able to examine the collection and to recognize among certain of the specimens that had been put aside as not belonging to known genera, plates of a new Antiarchan,
Remigolepis
Stensiö, which he has found in the Upper Devonian rocks of East Greenland. He also allowed me full use of the proofs of his recent paper (
Stensiö, 1931
), in which the new genus is described. I am obliged to Dr. W. D. Lang and Dr. E. I. White for the provision of facilities at the Natural History Museum, South Kensington, and to the Royal Commissioners for the Exhibition of 1851 for granting an extension of my scholarship to enable the work to be carried out.

II. G
eology

(i) Harvey's Range.—By far the greatest part of the collection comes from Harvey's Range, north-north-east of Parkes, where the fossiliferous formation is a coarse sandstone in which the broken plates are preserved as moulds, the rock being
The Upper Estuarine Series of Northamptonshire and Northern Oxfordshire
Authors: Thompson Beeby
Published: October 2009

In Northamptonshire, between the Lincolnshire Limestone and the Great Oolite Limestone in the north-eastern part of the county, and between the Northampton Sand (or the Lower Estuarine Beds) and the Great Oolite Limestone in all other parts of the county, occurs a series of variable beds, largely variegated clays containing abundance of vegetable matter of probably freshwater origin, interspersed with brackish-water beds and with distinctly marine beds. To this aggregate J. W. Judd, in 1867, gave the name ‘Upper Estuarine Series’, which he then thought represented the Stonesfield Slate or Lower Zone of the Great Oolite of the more south-westerly parts of England, Oxfordshire in particular.

In Northern Oxfordshire, between certain Inferior Oolite Limestones or White Sands (the time-equivalents of the Lincolnshire Limestone), or ferruginous sands (the equivalents of the Variable Beds of the Northampton Sand or even the ironstone series) below, and the Great Oolite Limestone above, occurs a series of beds which in various parts physically, and in others palæontologically, agree, as does the complete set in sequential position, with the Upper Estuarine Series of Northamptonshire.

It is an important object of this part of the paper to show how the Northamptonshire and Oxfordshire sections at this geological horizon may be more definitely correlated. The name ‘Upper Estuarine’ is retained for the complete series in both counties as free from the complication of an incomplete local place-name (Chipping Norton Limestone Series) and an incomplete and unsatisfactory palæontological one (Neæran Beds).

In attempting to correlate a variable set of
The Geological Structure of the Eastern Mendips
Authors: Welch Francis Brian Awburn
Published: October 2009

I. Introduction

The area under discussion comprises that part of the Mendip Hills lying east of a north-and-south line from Oakhill to Shepton Mallet, and extending eastwards as far as Frome.

Investigations were begun by Miss A. E. Bamber and Miss B. Gullick, who, being later prevented from continuing their undertaking, allowed me to conduct my research over their territory. They gave to me all their notes and maps, which have been of much use and for which I wish to express my gratitude. The later stages of my work were completed whilst holding a Carnegie Teaching Fellowship in the University of St. Andrews. I should also like to take this opportunity to thank Dr. Stanley Smith for his examination of the D
3
material, and Miss H. Muir-Wood for naming certain Productids.

The summary of literature dealing with this area, since it must of necessity be almost a repetition of that given in my paper (1929) on the adjoining area to the west (the central Mendips), will be omitted here. Two papers, however, by Prof. S. H. Reynolds (1907 & 1912) describing the Silurian inlier in the eastern Mendips, and one by G. E. Bush (1925) on the Avonian of Vallis and Spring Gardens were not included in that summary.

Geologically, the area consists of the Beacon Hill pericline, which is the most southerly situated of the four echeloned periclines constituting the Mendip Hills. This pericline forms an approximately east-and-west ridge which attains at its western end a maximum altitude
A Revision of the British Carboniferous Members of the Family Loxonematidæ, with descriptions of New Forms
Authors: Longstaff Jane
Published: October 2009

I. Introduction

The characteristics of the genus
Loxonema
Phillips, and of the genotype
L. sinuosum
(J. de C. Sowerby), have previously been defined by me (1909, p. 329). Since the latter is of Silurian age, it is not surprising that none of the British Carboniferous forms hitherto referred to the genus strictly belong there, though some are referable to genera and sub-genera into which the family Loxonematidæ Koken has been divided.

Before describing new forms it seems advisable to review the older ones. Etheridge (1888, pp. 299, 300) records nineteen Carboniferous species, but only eleven of these can with any degree of certainty be referred to this family.

Though
L. lefebvrei
Léveillé is a characteristic member and has been described by de Koninck in Belgium, I have not so far met with it in the British Isles, and I have been unable to examine the minute Irish forms,
L. galvani
and
L. minutissimum
Bailey (1860, p. 103). The figures of these species, however, are not suggestive of the family.
Loxonema galvani
is compared with
Pyramis reticulata
Brown, which I have seen and can state is not a member of this family.
Loxonema turrita
M
c
Coy does not appear to be in existence, and the figure given is not that of a
Loxonema
.

The only example of
Buccinum curvilineum
Phillips, in the Gilbertson Collection, does not belong here. The holotype Melania tumida Phillips is lacking in that collection, and a specimen there so named is not conspecific, as the form is different
The Geology of the Fairbourne-Llwyngwril District, Merioneth
Authors: Jones Brynmor
Published: October 2009

I. Introduction

This paper deals with that part of western Merioneth which lies between the village of Arthog and the town of Towyn. The area is included in a rectangle, the longer side of which runs north-east and south-west and is 8 miles long; the shorter side has a length of 3 miles. The western and northern boundaries are formed by Cardigan Bay and by the estuary of the River Mawddach. On the southern side, the area is bounded by the alluvium of the River Dysynni, and the south-eastern margin is the old Roman road which runs from Llanegryn to Dolgelley. The region is comprised within the Ordnance Survey 6-inch map, quarter-sheets Merioneth 36 S.W. & S.E., 40 S.E., 41 N.W., N.E., & S.W., 45 N.E., and 46 N.W., and within the Geological Survey 1-inch map, Sheet 59 N.E. (Old Series).

The topography of the district to be described is in marked contrast to that of the country adjoining it on the north-east, which includes the range of Cader Idris and its foot-hills. Sharp, craggy ridges are absent, the hills having smooth, rounded outlines and grassy slopes. The even contours are largely due to a mantle of glacial drift which smooths out pre-glacial irregularities and in many places conceals the solid geology.

The greater part of the area is upland country of low agricultural value, woodland being absent and the general aspect monotonous and bare. The maximum elevation, on Pen-y-garn, is 1500 feet above O.D. The main lowland region lies
The Geology of the Country between Abergwesyn (Breconshire) and Pumpsaint (Carmarthenshire)
Authors: Davies Kenneth Arthur
Published: October 2009

I. Introduction

In 1926, I described the area between Abergwesyn and Drygam, and subsequently the district on the north-east, between Abergwesyn and Rhayader, formed the subject of another paper (Davies, 1928). The present work is a continuation of the previous surveys, and deals with the country between Abergwesyn and Pumpsaint in Carmarthenshire (see fig. 1). The southern boundary is the main road from Lampeter to Llanwrda, while the northern and western limits are defined by the Towy–Teifi watershed.

The area forms part of the western flank of the Towy anticline, and has been mapped on the scale of 6 inches to the mile. It is about 130 square miles in extent, and is included within the Geological Survey maps, Old Series, 1-inch sheets 41 and 56 S.W. It is essentially that part of the Central Wales plateau which is drained by the upper Towy and its tributaries. The country is given over almost entirely to sheep-farming, and on the north-west it is desolate and somewhat inaccessible.

II. Historical Summary

Sir R. I. Murchison (1839, p. 342) mentioned the ‘slaty rocks and their associated conglomerates’ which are found on the north-west of the better-known areas with shelly fossils. He placed these slaty rocks within the ‘Cambrian’ system, and referred especially to Rhandirmwyn, where lead-mining was being carried on even at that time.

The Geological Survey Horizontal Sections, published in 1844 and 1845, throw some light on the nature of the folding, for No. 3 passes through Ogofau, near Pumpsaint, and No.
The Geology of Eastern Jersey
Authors: Mourant Arthur Ernest
Published: October 2009

I. Introduction

The island of Jersey stands in a key position between Normandy and Brittany; being easily accessible to English geologists, it also forms a valuable link between the rocks of England and France. Yet the work of many scores of investigators has not sufficed to determine satisfactorily the age and structure of its rocks or to bring to light the concealed structures which join it to Normandy and to Brittany. In this paper some advance is attempted in these directions.

The island is roughly rectangular, 10 1/2 miles from east to west and 6 1/2 from north to south. It forms a dissected plateau, some 300 feet high, overlooking the sea in the north but terminating against discontinuous coastal plains elsewhere.

The north-eastern corner of Jersey is formed of conglomerate and the other three corners of plutonic rocks. Between the granites in the western half of the island is a series of unfossiliferous mudstones and shaly grits, generally known as shales. Most of the eastern half of the island consists of volcanic rocks.

The area described in the present paper includes all the volcanic group, together with certain sediments and intrusive rocks lying to the north-east, south, and west of them. The whole of the eastern half of the island is dealt with except the highly complicated intrusions of the south-eastern coast. The thin layer of Pleistocene deposits which covers much of the solid geology is not considered in this paper.

The area
The Geology of the Marcapata Valley in Eastern Peru
Authors: Douglas James Archibald
Published: October 2009

I. Introduction

This paper is the result of an invitation extended to me to accompany as geologist an expedition sent out to South America in August, 1929, to investigate certain alluvial gold-mining concessions situated on the eastern side of the Andean Cordilleras in Peru. The area covering these concessions (fig. 1) lies in the Montaña or forested region of the upper Amazon basin in the province of Quispicanchi, Department of Cuzco, about 100 miles north-east of that branch of the Southern Peruvian Railway which runs from Puno on Lake Titicaca to the ancient capital of Cuzco. It comprises a stretch of country some 20 miles long by 5 miles wide lying in the angle formed by the junction of the Nusiniscato and Marcapata rivers; the latter, also known as the Araza, being one of the main tributaries of the Inambari, which itself is an affluent of the Madre de Dios.

The western boundary of the area is formed by the Quitari River and its tributary the Yanahurco. The greater part of this area was surveyed topographically for the first time during the course of the expedition, and the direction and relative position of many of the rivers were found to be incorrectly shown on existing maps of Peru.

The Marcapata Valley, by which access is gained to the interior, has its origin in a group of high, snow-clad mountain peaks, Mounts Ausangate, Callangate, Huiscachani, and Chimboya. These together constitute the so-called Vicanota knot, a transverse ridge uniting the two parallel
The Geology of the Scheelite Mine, Kramat Pulai Tin Limited, Kinta, Federated Malay States
Authors: Willbourn Eric Stewart , Ingham Frank Tinley
Published: October 2009

I. Introduction

This paper has been written to place on record the very considerable differences that exist between this occurrence of scheelite ore at Kramat Pulai and the other important scheelite deposits of the world.

Although specimens of scheelite have been found in fairly numerous localities in the mineralized calcareous rocks of Malaya, few deposits of the mineral are known to be of economic value, and those at Kramat Pulai are the most important source of tungsten ore. The occurrences will interest all who are concerned with the genesis of ore-deposits, for they consist almost entirely of fluorite and scheelite, with a very small admixture of quartz and other minerals; in this they differ from the scheelite deposits described by F. L. Hess (1917 and 1921) and by Hess and E. S. Larsen (1921).

The authors wish to make acknowledgment to Mr. J. B. Scrivenor for the help afforded by the results of his work, undertaken when the mine was first worked and when soil and alluvium obscured the structure to a greater extent than they do now. Their thanks also are due to Mr. F. H. Symonds, General Manager of the Company, and to Mr. J. Weekley, his Assistant, who have much helped the investigation. They are indebted also to Mr. J. G. Shenton, Chemist, Geological Survey Department, Federated Malay States, for supplying the necessary chemical analyses.

The Kramat Pulai Tin Company, Limited, holds mining leases covering an area of 2418 acres clustered round the old village of Pulai,
The Influence of Geological and Climatological Factors on the Distribution of Non-Marine Fossil Reptiles and Stegocephalia
Authors: Nopcsa Baron Francis
Published: October 2009

Introduction

The object of this paper is to determine how far the distribution of Palæozoic and Mesozoic terrestrial Tetrapods was influenced by geological and climatological factors.

In the first place, it is necessary to enumerate the known identical or closely allied poikilothermous Tetrapods in different parts of the globe in chronological order, and to investigate how far this distribution of terrestrial animals is in accord with the extension of former oceans. Next, there is the question of the land-bridges used by these animals; and, finally, it must be shown to what extent climatological factors were concerned.

In this investigation, terrestrial vertebrates are much more important than invertebrates, for the structure of vertebrate fossils gives much more information about their biology and their possibilities of migration than does the structure of most invertebrates, especially that of the ammonites, which are, nevertheless, the fossils particularly favoured by geologists.

The first two parts of the paper, therefore, dealing severally with the characteristic pre- and post-Liassic Tetrapods, are purely stratigraphical; the next part deals with the palæogeography of the globe as indicated by marine faunas; and the fourth part discusses tectonics. To some extent, the general ideas put forward in the fourth part are new, so that in that part several facts are mentioned which have nothing to do with the dispersal of the Tetrapods, but are weighty arguments supporting the new views on tectonics. The best proof of the soundness of these views will be found in the palæoclimatological part, for there is
The Glacial Gravels of the Market Weighton Area and Related Deposits
Authors: Melmore Sidney
Published: October 2009

I. Introduction

The conditions obtaining in the Vale of York during the Glacial Period are generally considered to have been as follows. A glacier from the Lake District passed over Stain-more and continued to flow eastward until such time as the Scandinavian ice impinged upon the coast. The estuaries of the Tees and Humber then became blocked, forcing the Stainmore glacier down the Vale of York and simultaneously giving rise to a “Lake Humber” south of York and a “Lake Pickering” east of Malton. These events must have occurred during the period of deposition of the Basement Clay of Holderness. The Scandinavian ice then retreated sufficiently to allow Scottish ice to pass down the coast. Finally, during the Hessle Clay period, the ice reached as far south as York, and in Holderness as far west as Driffield and Kipling Cotes.

Unless, therefore, the Basement Clay blockage had a permanent effect, there would be a return to the old directions of drainage until a second closure caused a repetition of lacustrine conditions.

In brief, there must have been a “Lake Humber” on at least two separate occasions, but direct evidence has never been forthcoming of the existence of more than one.

Moreover, in the Vale of York, the recognition of boulder-clays of different ages is difficult, since each glaciation would produce the same conditions; glaciers would travel along the same courses as before, giving rise to boulder-clays lithologically identical. There would be no means of separating them except by an appeal
The Skiddaw Granite and its Residual Products
Authors: Stansfield Kitchen Charles
Published: October 2009

Introduction

The Skiddaw granite occurs in an area that has long been noted for its interesting and varied assortment of rocks and for the complexity of its geological structure. Jameson's “Mineralogy”, published in 1820, mentions certain minerals as occurring “in granite, near the source of the river Caldew, Cumberland”, while the Sinen Gill and central outcrops of the granite are marked on William Smith's first geological map of the county, which appeared in 1824. No important geological work seems to have been done in this district, however, until 1870, when J. Clifton Ward carried out the first official geological survey. In addition to mapping the area, he contributed a Survey Memoir (Ward, 1876) and also a paper dealing with the granitic rocks of the Lake District (Ward, 1875–76), which includes an account of the Skiddaw granite.

At a later date the district received the attention of A. Harker (1894), who published a notable work dealing with the marginal variations of the gabbro of Carrock Fell, and with its associated rocks. A paper which requires special notice in the present discussion, however, is one by the same author which appeared in the following year (Harker, 1895). In this he deals with the greisen of Grainsgill (formerly termed by Ward a “very quartzo-micaceous granite”) and discusses its relationship to the Skiddaw granite. He concluded that this rock represents the mother-liquor extruded from the granite by earth-movements after crystallization had proceeded to some extent in that body.

At a still later period the
The Contaminated Tonalites of Loch Awe, Argyll
Authors: Nockolds Stephen Robert
Published: October 2009

I. Introduction

At the south-eastern corner of the great Cruachan “granite” mass, near the head of Loch Awe, there is a small area of the “granite” (tonalite) which is isolated from the main mass (see Fig. 1). It is bounded on the north and west by diorite and porphyrite, on the east by quartzite (the Glencoe quartzite) and on the south by a series of variable sediments which are now thermally metamorphosed to a considerable degree.

The present contribution is concerned mainly with a small portion of the south-eastern side of this tonalite area. At its immediate contact with the surrounding sediments the tonalite becomes extremely rich in xenoliths in certain parts, and holds large blocks and smaller fragments of the sedimentary rocks in all stages of disintegration and dissolution. As exposed in the old quarry, the xenolithic band is about 30 feet wide, but in other parts it is much narrower. The phenomena to be described are, therefore, of strictly local character, though this does not detract from their interest. Outside this xenolithic band there is little scattering of the xenoliths, and the zone passes sharply into tonalite which is almost free from them. As the sedimentary series into which the tonalite is intruded on the southern side is banded, the xenoliths vary from one area of the tonalite margin to another (Fig. 2). Locally, they have modified the original tonalite in different ways, and in the following pages the main types of contaminated tonalite with their accompanying xenoliths
The Genesis of the North Pennine Ore Deposits
Authors: Dunham Kingsley Charles
Published: October 2009

I. Introduction

The North Pennine area of northern England, drained by the Tyne, Wear, and Tees and their tributaries, is a dissected plateau, uplifted along the Pennine fault-line to the west, and sloping gently down to the lowlands of East Durham. Its physiographic boundaries are, on the north, the main valley of the Tyne; on the west, the Pennine escarpment, overlooking the Vale of Eden; and on the south, the natural pass of Stainmoor. This region has been called the “Alston Block” by F. M. Trotter and S. E. Hollingworth (1928). Gently domed Carboniferous sediments resting on an eroded surface of closely folded Lower Palæozoic slates and volcanic rocks form the country-rock, and the area is structurally a fault-block, the limits of which correspond closely with the physiographic boundaries. The Carboniferous limestones, sandstones, shales, and coals have a total thickness of more than 5000 feet, and throughout their whole thickness rhythmic alternations of beds are well exhibited. In the Carboniferous Limestone series (S
1
-D
1
), which is the lowest Carboniferous member, limestones predominate. Limestones are co-important with sandstones and shales in the overlying Yoredale series (D
1
-D
3
), but are absent from the higher horizons. Coal seams alternating with sandstones and shales make up the Upper Carboniferous succession. As a result of the gentle outward inclination of the beds from the highest part of the dome, near Cross Fell, progressively higher horizons outcrop round the northern, eastern, and southern margins of the area. The Millstone Grit thus appears along the Tyne valley and over
The Cairnsmore of Carsphairn Igneous Complex
Authors: Deer William Alexander
Published: October 2009

I. Introduction

The Cairnsmore of Carsphairn plutonic mass occurs in the north-eastern corner of sheet 8 and adjacent sheets of the Geological Survey 1-inch map of Scotland. It is the smallest of the four large plutonic masses intruded into the Lower Palæozoic rocks of south-western Scotland. The complex has been injected into the Arenig, Glenkiln, and Hartfell beds represented by well-marked conglomerates and pebbly grits, blue greywackes, blue flags, and dark shales.

The plutonic rocks occupy a roughly triangular area a little over three miles in width and extending nearly 2½ miles from north to south. The country occupied by the complex is essentially the Cairnsmore mass (2612 feet). The “granite” just fringes Dunool (1758 feet), Beninner (2328 feet), Moorbrock (2136 feet), and Black Shoulder (2257 feet). Hitherto no detailed work has been done on the igneous rocks. The Carsphairn “granite’ was referred to briefly in “The Silurian Rocks of Britain” (Teall, 1899). No microscopical descriptions were published, although the mass was known to include a number of distinguishable types.

II. The Plutonic Rocks

The intrusion consists of at least four well-defined plutonic rocks. There is a small central mass of granite, surrounded first by a finer grained granite-tonalite hybrid and then by a tonalite, and finally there is an outer heterogeneous area of much varied character.

The acid hybrid between the granite and the tonalite forms a continous and comparatively wide outcrop. The tonalite also occurs in a continous ring broadening towards the north, where it is in contact
On the Nature, Origin, and Climatic Significance of the Coral Reefs in the Vicinity of Oxford
Authors: Arkell William Joscelyn
Published: October 2009

I. Introduction

The origin of the Coral Rag is a problem that has appealed to the imagination of many writers. Some (Wright, Duncan, Hull, Blake and Hudleston) have held it to consist of true fossilized coral reefs, and some have drawn glowing pictures of its formation under a tropical sun; but these have usually evaded the climatic and palæogeographical implications of their enthusiasm. Others (Phillips, H. B. Woodward) have been too cautious to admit that it represents anything but beds of “drifted” or “rolled” corals. But since the corals are obviously reef-builders and are present in large quantities, and no one has suggested that they have been rolled all the way from the tropics, it is difficult to see what advantage the cautious school have over the relatively reckless.

The literature of modern coral reefs has now grown so vast that it is altogether disproportionate to that of fossil formations of comparable origin. Yet the fossil reefs are so important for the light they throw on past climates, ecology, tectonics, and paleongeography, as well as on the evolution and biology of corals, that the time is overdue for an attempt to describe some of them more accurately and to discuss their significance.

Probably no better opportunity than the present has ever occurred for a re-examination of these questions. Around Oxford and the neighbouring town of Abingdon, villas are springing up along every road, and each affords holes for foundations, wells, and cesspools. The water-supply schemes have involved borings and excavations
The Charnockite Series of Uganda, British East Africa
Authors: Groves Arthur William
Published: October 2009

I. Introduction

Though Sir Thomas Holland (1900, p. 131) counselled that the designation “charnockite series” should not be applied to apparently similar rocks outside India unless their genetic relationship with the type series could be proved, the striking parallelism between that series and the rocks to be described in this paper appears to justify reference to the latter as “the Uganda chamockite series”.

The Uganda series comprises four main divisions—acid, intermediate, basic, and ultra-basic—and includes nearly all the types known in India. In Uganda, as in India, the sub-acid to basic types predominate. Hypersthene-bearing rocks were discovered at several localities in Bunyoro by E. J. Wayland and W. C. Simmons, and subsequently in Karamoja by Wayland and in the West Nile District by Simmons. A few of these rocks were provisionally identified in the field as “charnockites”, but the existence of a series of rock types akin to the charnockite series of India was not established until 1931, when I was able to make a complete petrological study of the collections. Hypersthene-bearing rocks were then found to be more abundant and more widely distributed than had hitherto been suspected, their occurrence being discovered in many new localities in each of the three main areas just mentioned.

The present paper is based on a study of 110 specimens of the charnockite series, 10 representative rock analyses, nine analyses of minerals, and a large number of specimens of country rocks.

II. Distribution and Mode of Occurrence

The outcrops of the charnockite series
The Mourne Dyke Swarm
Authors: Tomkeieff Sergei Ivanovich , Marshall Charles Edward
Published: October 2009

I. Introduction

J. F. Berger (1816) in his paper read before the Geological Society noted the uniform north-west and south-east direction and the parallelism of practically all the dykes of the north of Ireland now known to be of Tertiary age. The exhaustive researches of the Geological Survey upon the Tertiary province of Scotland confirmed this observation.

The Tertiary dykes of North Ireland may be roughly divided into two major sets:—

(1)

The Antrim set—more or less coinciding with the area of plateau-lavas.

(2)

The Donegal-Down set, stretching diagonally across North Ireland and probably continuing across the floor of the Irish Sea to Anglesey, North-West Wales, and the English Midlands. The dykes of this set are frequently exposed in elevated regions inland, but are best seen along the seashore. The coast from the entrance of Strangford Lough southwards to Dundalk Bay affords an excellent section for the study of the Donegal-Down set, and here three concentrations of dykes can be discerned. Provisionally, we propose to regard these as three separate swarms: namely, (a) the Ardglass swarm, (b) the Mourne swarm, and (c) the Carlingford swarm.

As rock-exposure largely fails along the coast between these three concentrations, it is not known whether they are separated by areas in which intrusions become sparse. The fact, however, that the Carlingford and Mourne dykes coincide geographically with plutonic massifs suggests that they are indeed swarms in the accepted sense of the term. In the case of the Ardglass concentration, however, there is no visible
The Pleistocene Fauna and Flora of Kharga Oasis, Egypt
Authors: Wight Gardner Elinor
Published: October 2009

I. Introduction

T
he
life of an isolated area, be it island or oasis, has a special interest of its own, and this is no less true of the past than the present. Indeed, in the case of Kharga Oasis, the interest is heightened by the fact that this region is now naturally a desert: where life once flourished there is now no sign of shell or shrub.

What kind of fauna and flora lived in the depression in Pleistocene times, whence and by what means did it come, what were its reactions to the existing conditions, and why did it go?

The facts that have been accumulated in three seasons' work (1930–1933) will be marshalled in the following paper in an attempt to answer these questions, but a short sketch of the oasis and its later history must first be given to make the faunal discussions intelligible; a fuller account is in my paper in the
Geological Magazine
for 1932 (vol. lxix, p. 386).

Kharga Oasis is an elongated depression some 185 kilometres from north to south by 80 broad, lying between latitudes 24° and 26° north. It is sunk from 300 to 400 metres below the general level of the Libyan plateau, which separates it from the Nile by 140 kilometres of waterless limestone. The eastern and northern boundaries are sharply defined by steep scarps capped by Eocene or Cretaceous limestone. The later fossiliferous deposits occur mainly along the eastern scarp and consist of gravels, silts, and tufas, mostly
The Base of the Gault in Sussex
Authors: Kirkaldy John Francis
Published: October 2009

I. Introduction

Recent detailed stratigraphical work on the Mesozoic rocks has shown very clearly the importance of careful study of the age and lithology of beds which indicate the presence of transgressions, or of pauses in the deposition of sediment. Arkell, in his well-known monograph (1933), has shown the extreme importance of this in unravelling the history of the Jurassic period, but unfortunately our knowledge of similar phenomena in Cretaceous times is not nearly so complete or to be found in so accessible a form.

The presence of a marked break in deposition and, in some areas, of widespread transgression at the base of the Gault clays is well known, but the details of the exact age and lithology of the basal beds of the Gault have only been worked out in the belt of country lying at the foot of the main Chalk escarpment of England (Kitchin and Pringle, 1920, 1922). In the Weald, the facts are less completely known, whilst those available are only to be found after search through a score of separate publications. It is in an attempt to fill in a part of this gap in our knowledge that the present study of the base of the Gault between Petersfield and Eastbourne is offered.

The bulk of the literature relating to the Cretaceous beds of the southern Weald is to be found in the Memoirs of H.M. Geological Survey. In these volumes, the presence of a sandy basement bed to the Gault, usually containing phosphatic
Cyathophyllum Cæspitosum Goldfuss, and other Devonian Corals considered in a Revision of that Species
Authors: Dickson Lang William , Smith Stanley
Published: October 2009

I. Introduction

Few names appear more frequently in the literature of Devonian palaeontology than “
Cyathophyllum cæspitosum
Goldfuss”; yet the descriptions of that species are most unsatisfactory, partly because a lectotype had not been chosen until lately (Lang and Smith, 1934, p. 80), and partly because the internal characters of the type specimens have not yet been made known. Occurring in a faunal list, the name usually connotes no more than a phaceloid coral.

Goldfuss described the coral in 1826, on page 60 of his classical work “Petrefacta Germanise”, and illustrated it by figures of four syntypes, from the Eifel and Bensberg, in pl. xix, figs. 2 a–d. He also described and figured, in the same work,
Lithodendron coespitosum
(p. 44, pl. xiii, fig. 4), which has been considered by many authors a synonym of
Cyathophyllum cæspitosum
; and
Cyathophyllum hexagonum
(p. 61, pi. xix, figs. 5 a–f; pl. xx, figs. 1 a, b), of which the examples illustrated on pl. xix, figs. 5 a–d, have also been cited as conspecific with
C. cæspitosum
. Through the courtesy of Professor Tilmann, who has very kindly lent us the types (preserved in Bonn University), we have been able to investigate the structures of these species, and to choose a lectotype of
Cyathophyllum cæspitosum
: namely, the specimen figured in Goldfuss, 1826, p. 60, pl. xix, fig. 2 b.

Since
Cyathophyllum cæspitosum
and
Lithodendron cæspitosum
cannot be included in either
Cyathophyllum
or
Lithodendron
, we have investigated the genotypes of the various genera to which those two
The Gabbros and associated Xenolithic Complexes of the Haddo House District, Aberdeenshire
Authors: Read Herbert Harold
Published: October 2009

I. Introduction

The investigation of the Younger gabbro masses of North-East Scotland was begun in 1914 by W. R. Watt in the Huntly district. Watt described picrite (peridotite), olivine-gabbro, troctolite, and norite, and showed that certain endomorphosed gabbros, such as cordierite-norites, “originated from a magma contaminated by the aluminous material of the phyllites.” After the War, I described the Huntly gabbro mass and portions of the Insch and Cabrach masses. During this work the endomorphosed cordierite-bearing types discovered by Watt were found to have a wide distribution (Read, 1923b). The term “contaminated rock” was introduced to denote a rock resulting from the solidification of a magma which had been modified by reaction with xenoliths, usually of sedimentary origin (Read, 1921). It was suggested that in the formation of these contaminated gabbros a reciprocal reaction between initial magma and sedimentary xenoliths had taken place. Later, additional analyses of xenoliths from contaminated gabbros of the Huntly mass were supplied in support of this view (Read, 1924).

Meanwhile, an account of the petrology of the Arnage district in eastern Aberdeenshire had been published in 1923 (Read, 1923a). In this, I held that contamination of gabbros had taken place on a large scale, with the formation of quartz-biotite-felspar-cordierite rocks (Arnage Type) and, as a final product, of a granitic rock (Ardlethen Type). Half a dozen years' work amongst the granitic complexes of Sutherland (Read, 1931a, pp. 99–164; Read & others, 1925, pp. 21–40; 1926, pp. 148–52), and a closer acquaintance with the “Older Magma”
Eclogites from the Neighbourhood of Glenelg, Inverness-Shire
Authors: Alderman Arthur Richard
Published: October 2009

I. Introduction.

References to the occurrence of eclogites in the western Highlands of Scotland are singularly scarce. Teall (1891) described an eclogite from Totaig Ferry, Loch Duich, about 5½ miles north-east of the Kirkton of Glenelg, and he observed that the existence of such a rock in the British Isles did not appear to have been previously recorded.

In the Geological Survey memoir which describes sheet 71 of the one-inch map (Clough and others, 1910) many references are made to the occurrence of eclogites and eclogitic rocks near Glenelg. As is explained in the memoir, no general attempt was made to map the margins of these rocks owing to their extremely complicated character. Many of the more important occurrences are described, however, and the areas in which such rocks are most abundant are indicated on the one-inch map. Although the chemical composition of none of the eclogitic rocks was determined, an analysis was made of a garnet from an eclogite near Beinn a' Chapuill.

Reference to the occurrence of eclogites in the Lewisian is made by Harker (1932) and an example from Glenelg is figured. Eclogitic rocks have also been recorded from central Sutherland by Read (1931) and An Cruachan in central Ross-shire (Peach and others, 1913).

The Glenelg area, in which the rocks here described occur, is shown in the eastern portion of the one-inch map, sheet 71, and is bounded in the north by Loch Alsh and Loch Duich, in the west by Kyle Rhea and the Sound
On Some Karroo Fishes from East Africa
Authors: Haughton Sidney Henry
Published: October 2009

From Mr. G. M. Stockley I have received a small collection of fish remains. Most of the specimens are incomplete, but the following notes will indicate the nature of the fauna, of which further collections will undoubtedly increase our knowledge.

The genus
Australosomus
was founded by Piveteau (
C.R. Acad. Sci., Paris, cxci
, pp. 456–8) on specimens from Madagascar which had been identified by Priem as
Pristisomus merlei
. Piveteau pointed out that the characters of the fish in question must cause it to be removed from Pristisomus, and he made the new genus the type of a new family which, in his opinion, possessed features of both the Palæoniscidæ and Saurichthyidae. In view of the fact that the genus is being further investigated by Dr. E. I. White, it is proposed here merely to draw attention to the occurrence of members of the same genus in the Karroo of Tanganyika.

The specimens under consideration were collected by Mr. Stockley at Vikindu, about 15 miles west of Pangani Rapids, near the Rufiji-Ruaha confluence. They are preserved in a calcareous shale, and most are weathered and fragmentary. Two of them, however, are nearly complete, and the chief features can be ascertained from these and from some of the fragments.

The complete fish was from about 100 to 105 mm. long, the head and shoulder-girdle together occupying about one-sixth of the total length. The maximum depth of the body is about 17·5 mm., so that the fish is more slender in build than
A. merlei
.