bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Geology of the Country around Bodfean, South-Western Carnarvonshire
Authors: Matley Charles Alfred , Heard Albert 
Published: October 2009

The following account deals with a tract of country in Western Lleyn (Carnarvonshire) between Nevin and Pwllheli, chiefly in the parish of Bodfean. It is about 3½ miles long (from west-south-west to east-north-east) and 2 miles wide, and consists chiefly of Ordovician extrusive and pyroclastic volcanic rocks of varied composition associated with marine sediments. The hill of Gam Bodfean that rises steeply to a height of 918 feet is the most prominent feature of the area, although it is overtopped on the north by the larger hills north-east of Nevin and on the south by Carn Fadryn. Moel y Penmaen is a smaller and less conspicuous ridge, about 500 feet high. Most of the remaining country is thickly mantled with glacial drift, which has prevented us from working out the geological sequence and structure as fully as we wished.
As this area lies near the margin of the regions which we are separately investigating, we decided to deal with it jointly.
Although both authors have taken part in the field work, the first-named is more particularly, concerned with the stratigraphy and palæontology, and the second author with the petrology.
With the exception of Garn Bodfean and the recording of fossils from Bodfean Hall, the area has hitherto received little attention from geologists. In 1843 Sedgwick described the Palæzoic region of Lleyn, of which the tract here dealt with forms part, in general terms as ‘composed of greywacke (sometimes passing into a coarse arenaceous rock), and greywacke slate,... and these rocks
Pre-Ordovician Rocks of the McDonnell Ranges, Central Australia
Authors: Mawson Douglas , Madigan Cecil Thomas 
Published: October 2009

During the last fifty years a number of explorers and a few trained geologists have contributed to our knowledge of the structure and lithology of the McDonnell Ranges, the inaccessibility of which has, until recently, been the obstacle limiting investigations. There has never yet been a thoroughgoing investigation of the area, and each observation has been in the nature of a brief reconnaissance in connexion with mineral resources or water-supply.
All work prior to the year 1925 is mentioned in an excellent summary and discussion contributed by Dr. L. K. Ward. For further information relating to such earlier work the reader is directed to that paper.
In his contribution Dr. Ward has combined and clarified the information gathered from these various sources, and he presents in excellent language a clear picture of the geology and physiography of the regions. The account also incorporates his own observations made on several occasions, when visiting the area in connexion with water-supply and mineral occurrences.
There is, however, one finding that appears in this very notable contribution which, while being a reasonable inference, could not be regarded as actually proven. This is a very important question: no less than the age of some 14,000 feet of sediments (Ward's measurement) and in a portion of which, at Acacia Well east of Alice Springs, Dr. C. Chewings had long ago reported the occurrence of cryptozoan fossils. The beds unconformably overlie the crystalline complex of accepted pre-Cambrian age.
Geologists had expressed diverse views on the matter. The
Report on the Fossil Wood from the South Central Sahara
Authors: Williams Samuel 
Published: October 2009

The material consists of a single block of silicified Gymnosperm wood collected by Francis Rodd on his last journey in the Central Sahara. The block measures 10 × 8.5 cm. (radial) × 8 cm. (tangential). It consists entirely of secondary wood, there being no trace of pith, primary xylem, or of any tissues outside the xylem. The preservation of the tissues is, for the greater part, poor, but certain areas are relatively well preserved, and permit of the following description.
Transverse sections (P1. XL, fig. 1) do not give any clear indication of the presence of ammal rings. There are, however, certain regions where, for a depth of two tracheids, the size of the latter is small compared with those on either side. The xylem appears to consist entirely of tracheids, there being no xylem parenchyma present. The tracheids themselves are of the Araucarian type, showing a single row of large contiguous pits which are flattened above and below (P1. XL, fig. 2). Very rarely the pits are in two rows, and, in these examples, the pits are placed alternately. The pits are confined to the radial walls. In transverse section many of the tmcheids show dark-brown contents, while in longitudinal section (P1. XL, figs. 3 & 4) the tracheids appear to be septate. These appearances are probably due to the presence of resin-plates.
The medullary rays (P1. XL, figs. 3 & 4) are invariably uniselriate, and are from 2 to 18 cells deep, the majority being from 5 to
The Age of the Midland Basalts
Authors: Pocock Roy Woodhouse 
Published: October 2009

In the course of work on the Midland Coalfields one of the many problems that have occupied attention has been the question of the age of the basalts associated with the Coal Measures.
Extrusive basic igneous rocks that are known to be of Lower Carboniferous age occur at Little Wenlock in Shropshire, in the Bristol district, in North Staffordshire, in Derbyshire, and in Cumberland. Rocks of similar type are present in the Upper Carboniferous of the Midlands, but hitherto no definite evidence of their age has been produced. The distribution of these rocks is shown on the accompanying map (Pl. I).
The Butterton and Swynnerton dyke in North Staffordshire and the Grinshill and Acton Reynald dyke in North Shropshire both traverse the Keuper Marl and are therefore definitely post-Triassic.
Kinlet.—The Kinlet basalt lies approximately between the Sweet Coal (Yorkian) and Sulphur Coal (Staffordian) Groups of the Wyre Forest Coalfield; that is, in the position of the unconformity or ‘Symon Fault’ in the Coalbrookdale Coalfield.

In an old quarry about 300 yards S. 20° W. of Mass House Farm, near Kinlet, the following section is exposed:—

Feet.
Inches

Sandstone, yellowish-buff, flaggy. The lower layers are dark btrn in colour and consist of sand grains in a matrix of decomposed basaltic material with pebbles of basalt and portions of amygdales.
2
0

Coarse grit of small quartz pebbles up
The Unroofing of the Dartmoor Granite and the Distribution of its Detritus in the Sediments of Southern England
Authors: Groves Arthur W. 
Published: October 2009

The Hercynian age of the Dartmoor granite is generally admitted, but little information has hitherto been available concerning the period at which this granite became contributory to sediments. The work described in this paper is an attempt to supplement this information by direct appeal to the sedimentary formations in the South of England. These have been systematically searched for detrital mineral species which, in respect of associations and both specific and varietal features, are in consistent agreement with the assemblage of accessory minerals characteristic of the Dartmoor granite as described by Dr. A. Brammall (1928).
Both the coarse and fine constituents of the Permo-Triassic strata in the West of England have been investigated within recent years. In the South of England pebble-beds of post-Triassic age are rare. For the special purposes of this paper, strata investigated by other workers have been re-examined, and gaps have been bridged by the study of intervening horizons.
The strata sampled and examined in the laboratory range from the base of the Watcombe Clay (Permian) to the Pliocene of the North Downs (Diestian), of St. Erth, and of St. Keverne in Cornwall. It was reasonable to assume that, in the chain of evidence sought, the first and strongest link would be found in the strata nearest the granite outcrop. West of the granite, however, the only strata known to be of post-granite age comprise a few small outliers of Permian and Pliocene.
The samples collected (about 250 in all) are fairly representative of the stratigraphical
Some Non-Marine Lamellibranchs from the Upper Part of the Coal Measures
Authors: Dix Emily , Trueman Arthur Elijah 
Published: October 2009

The present paper deals with those non-marine shells which occur in the upper part of the Coal Measures: namely, in the Phillipsi and Tenuis Zones and in the higher portion of the Pulchra Zone. Those studies of the non-marine Lamellibranchs of the Coal Measures which have recently been published, have been directed chiefly to shells from the lower portion of the Coal Measures (Davies & Trueman, 1927; Wright, 1929; Clift & Trueman, 1929; and Hopkins, 1928, 1929). The shells which occur in the upper portion of the Coal Measures are mostly species of the genus
Anthracomya,
which have hitherto afforded evidence for no more than a broad classification of those measures; in the following pages we have attempted to define with greater precision the characters and ranges of these species.

These investigations have been carried out with the assistance of grants from the Department of Scientific and Industrial Research, and we are particularly grateful for the generous way in which the Council of that Department has supported the work. One of us (A. E. T.) also wishes to acknowledge a grant from the Royal Society, which has defrayed certain expenses incurred during the early stages of the investigation.
Most of the material described in the paper we have ourselves collected, and we wish to express our indebtedness to mine-owners and others for the cordiality with which we have been assisted in the various coalfields where collecting has been done. We have also had the advantage, through the kindness of Dr.
The Geology of the Dolwyddelan Syncline (North Wales)
Authors: Williams Howel , Bulman Oliver Meredith Boone 
Published: October 2009

The importance of the Dolwyddelan syncline from a stratigraphical standpoint has long been recognized. It was considered by Ramsay to be a vital link or ‘key-area’ in the supposed correlation of the Snowdonian country with that of Bala. More recently, it was learned that the syncline contained graptolite-shales intimately connected with the Snowdonian volcanic rocks and offering definite evidence of their age. Considering, further, the unfortunate circumstance that on Snowdon itself the highest lavas are also the topmost beds, and that the lowest lavas are separated by a thick group of sediments from the highest graptolite horizon yet recognized there, the need for a re-study of the Dolwyddelan syncline, especially for more precise evidence as to the age of the Snowdon lavas, becomes apparent.
The limits of any syncline are, of course, arbitrary, and as our chief aim has been to examine the volcanic rocks and the sediments immediately associated with them, we have restricted ourselves to the re-mapping of a narrow zone extending for about a third of a mile on either side of the synclinal axis over a distance of some 6 miles. We have, in addition, made a reconnaissance traverse along the southern slopes of Moel Siabod in order to evaluate the relations of the Snowdonian lavas of the syncline to the Capel Curig lavas which underlie them.
The area illustrated on the map (Pl. XXXV) is also depicted on the 1-inch Geological Survey map (Old Series), Quarter-sheet 75 N.E., and comprises the 6-inch Quarter-sheet Caernarvon-shire 23
The South-West Highland Sequence
Authors: Green John Frederick Norman 
Published: October 2009

This paper deals with the succession in the ancient (Dalradian) rocks of a part of the Western Highlands of Scotland, in the immediate neighbourhood of the Great Glen Fault. Along the line of the fault the length of the area is a little over 100 miles, and it extends to 30 miles south-east of it. The greater part of this region, however, is occupied by later igneous rocks or by the sea, which exposes a vast series of coast sections. It presents special advantages to a student of the ancient formations owing to the fact that the rocks are nearly all in a low stage of metamorphism, often resembling ordinary Lower Palæzoic rocks; while the members of the small portions which reach the Biotite Zone or, near Loch Leven and Dalmally, the Garnet Zone can easily be followed into the less altered stages.
Further, most of the area is readily accessible and the student has the boon of a complete set of excellent 1-inch maps and memoirs (see index-map, fig. 1) published by the Geological Survey.
Without this detailed Survey work, recording the various rock-types in all places, no general synthesis would be possible, as the complexity of structure is too great for any isolated worker. Some such synthesis is very necessary, as no section of the Highlands offers better chances of a clue to the intricate problems of the Scottish Archæan.
Up to the present there has been little agreement as to the connexions between adjacent sheets. Islay was
The Upper Great Oolite, Bradford Beds and Forest Marble of South Oxfordshire, and the Succession of Gastropod Faunas in the Great Oolite
Authors: Arkell William Joscelyn 
Published: October 2009

The line of division between the Forest Marble and Great Oolite in the Oxford district has been drawn at two levels by various writers. As the stratigraphical position of a rich and distinctive lamellibranch and brachiopod fauna is involved, together with that of a few gastropods and corals and the deinosaur
Ceteosaurus oxoniensis
, the question of the substage to which the beds containing them belong is of more than local importance.

The earliest writers on the subject, E. Hull and J. Phillips, who published descriptions of the sections at Kirtlington (Bletchington) Station and Enslow Bridge, about 8 miles north of the centre of Oxford, in 1859 (pp. 20, 21), and 1860 (pp. 117–18) respectively, already held differing views about the position of the junction.
Hull, who favoured a higher position than that adopted by Phillips, brought a wide experience of these formations, gained in the Cotteswolds, to bear on the Oxford district. It is significant that Hull's conclusions with regard to the relations of Forest Marble and Great Oolite at Kirtlington and Enslow Bridge were accepted and applied to the neighbouring sections at Hailey, Bladon, Shipton-on-Cherwell railway-cutting, and Islip by H. B. Woodward, who had already travelled over the whole outcrop in the South-West of England in the course of preparing his great work on ‘The Jurassic Rocks of Britain’, and who brought an even greater experience to bear on the subject than Hull (Woodward, 1894, pp. 372–7).
There followed in 1908 the Geological Survey Memoir in explanition of the
Fossil Plants from the Bokkeveld and Witteberg Beds of South Africa
Authors: Seward Albert Charles 
Published: October 2009

I. I
ntroduction

N
ine
years ago Dr. S. H. Haughton of the Geological Survey of the Union of South Africa sent to me for description a collection of fossil plants from the Bokkeveld and Witteberg Series of the Cape Province. At my suggestion Mr. S. L. Ghose, who was then a Research Student of Selwyn College, examined the material and incorporated a preliminary account of it in an unpublished thesis. Subsequently, Dr. T. M. Harris made a careful examination of the fossils and it was our intention to publish a joint paper : unfortunately, pressure of other duties rendered this impossible. I am greatly indebted to both these gentlemen, but I must accept responsibility both for the delay and for the conclusions reached in the present communication.

The specimens described in the following paper were obtained by Dr. Haughton from the upper part of the Bokkeveld Series at Schiet Kraal, Steytherville, in the south-central part of the Cape Province, about 80 miles north-west of Port Elizabeth, and from the Witteberg shales at Nourse Poort, Steytherville. One of the specimens (PI. XXIII, fig. 7) was found at a farm east of the Bezuidenhouts River, Uitenhage, in beds described by Dr. Haughton as the second shales of the Bokkeveld beds.
In a letter written by Dr. Haughton (December 14th, 1922) he stated that the plant-bearing shales described as Upper Bokkeveld should be assigned, from a palaeontological view, to the Witteberg Series. He added that ‘ in the field there is no clear line
Contact Metamorphism in South-Eastern Dartmoor
Authors: Fitch Albert Alfred 
Published: October 2009

I. H
istorical
I
ntroduction

T
he
area mapped and described comprises Sheets CXIV S.W., CXIX N.E. and S.W., CXX N.W., and CXXV N.W. and N.E. of the six-inch Ordnance Survey series, Devon.

The history of research in the area may be considered to show three phases : (i) the pioneer observations, extending up to 1811; (ii) the investigation of the sequence and structure of the rocks outside the metamorphic aureole; and (iii) the investigation of the petrogenesis and structure of the rocks comprising the granite intrusion and its metamorphic aureole. The previous work (see list of references, pp. 604-7) deals with the second phase in some detail, but the third has received less attention. This paper will treat of the petrogenesis and structure of the thermo- and dynamo-metamorphosed rocks.
The earliest observations on the area which are of geological interest are found in the two early ‘surveys ’of the county of Devon by Risdon (1610) and Westcote (1630) respectively; they refer to the Brent lodestones. An account of a large Devon magnet, probably from Brent, is given in volume 2 of he Philosophical Transactions. Chapple (1785) gives further details of the Brent magnets. Following these come some notices of the occurrence of various rocks in the ‘agricultural surveys ’ of Fraser (1794) and Vancouver (1808), the general county histories of Polwhele (1797) andand Lysons (1822), and the ‘Natural History’ of Bellamy (1839).
The earliest petrographical observations are due to Maton, a keen observer, who thus described the Dartmoor granite in 1797: ‘The
The Geology of the Ruhuhu Coalfields, Tanganyika Territory
Authors: Stockley Gordon Murray 
Published: October 2009

I. I
ntroduction

F
rom
June to October of 1930 it was my good fortune to survey the coalfields of the Njombe and Songea districts of Tanganyika Territory, east of Lake Nyasa; an area of some 1500 square miles, of which 1330 square miles are occupied by Karroo rocks. The coalfields stretch eastwards from the shore of the lake, their eastern boundary being formed by the disused motor-road from Songea township to Njombe; the northern and southern limits are defined by the faulted boundaries of the Karroo formation. The extension of the Karroo rocks beyond the eastern boundary is unknown; it is probable that they continue in a north-easterly direction as far as to the Rufiji River. An account of the coalfields, with especial reference to their economic possibilities, is in course of publication in a Government Bulletin. The description of the geology given in the present paper will serve as an introduction to the papers dealing with the palæontology of the Karroo rocks.

Very little work had been done in this area previously, although German geologists had determined roughly the extent of the Karroo formation.
Bornhardt (1900)
, the first geologist to visit the district, had examined a coalfield south of Manda in 1895-7 and condemned it. His observations are summarized by
Koert (1913, pp. 195-6, translation)
as follows:—

‘Bornhardt speaks of the Ruhuhu as a tableland intersected by faults, and divides up its beds as follows:—
River depression. The following were identified in the collection:—
(i) Petrified Fossil Wood from the
On a Collection of Karroo Vertebrates from Tanganyika Territory
Authors: Haughton Sidney Henry 
Published: October 2009

I. I
ntroduction

T
he
vertebrate bones described and discussed in this paper are part of a consignment sent for examination by Dr. E. O. Teale, Director of the Tanganyika Geological Survey, and collected by Mr. G. M. Stockley of that Survey in the Ruhuhu area of Tanganyika Territory. Gathered as they were during the course of a survey undertaken primarily for the study of the economic possibilities of the area, the bones consist almost entirely of weathered pieces picked up on the surface. They were sent to Cape Town in seven boxes, each piece of bone being marked with a special number which corresponded to a locality on Mr. Stockley's field-sheets.Examination showed that some of the fragments could be accurately fitted to make more or less complete bones or recognizable parts of a skeleton; in some cases fragments said to come from different localities were found to fit together, owing to errors in marking. Many others remained isolated, for one of two reasons: either the bone had been broken and rolled before being buried in the sediments, or the remainder of the pieces that were originally attached to it had not been collected.

Enough, however, has already been found to show that Mr. Stockley has discovered an area of great interest to students of the Karroo vertebrate material; and my thanks are due to him and to Dr. Teale for the opportunity of studying this interesting but tantalizing collection.
The following pages contain a description of the bearing
The Rocks between the Carboniferous and Trias in the Birmingham District
Authors: Boulton William S. 
Published: October 2009

I. Introduction
In 1924, I described a group of breccias (Nechells Breccia) which was revealed by borings through the Trias in the eastern part of Birmingham (Boulton, 1924), and I attempted a correlation of the Nechells Breccia with other well-known pre-Trias breccias in the Midlands, including those of Clent and Northfield, some six miles south of Birmingham, and the Hopwas Breccia to the north, in the neighbourhood of Hopwas and Sutton Coldfield.
Evidence was adduced to show that all these breccias, with their associated sandstones, lie unconformably on the Calcareous Conglomerate group (Lower Enville Beds of the Geological Survey) or the Keele Beds, and that they are separated by a break from the overlying normal Bunter beds. Further, I suggested that in the absence of palaeontological evidence they should be retained in the Permian, in which system the Clent and Northfield breccias had been placed since the time of the original survey.
At that time (1924) the Survey were completing their 6–inch maps and memoirs of the district, and they adopted an interpretation somewhat different from mine. The Nechells Breccia was by them correlated tentatively with the Hopwas Breccia and linked up with the Trias, while the Clent and Northfield breccias were included in the Carboniferous (Geological Survey, 1925). No appreciable unconformity at the base of the Clent Breccia was admitted by the Survey, but only such small local discordance as one might expect at the base of such materials as scree beccias. Incidentally, the effect of the Survey classification