bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Geological Interpretation of the Earth - Movements associated with the Californian Earthquake of April 18th, 1906
Authors: Oldham Richard Dixon 
Published: October 2009

The Californian earthquake of 1906 was accompanied by very considerable displacements of the ground along a great fault-line, which has been traced for a distance of about 200 miles from its southern extremity to the point where it finally passes out under the sea. As several stations of the principal triangulation lay within the disturbed area, the Government of the United States decided to repeat the observations over this area, and determine with accuracy the present positions of the points previously fixed. The result of this work has been issued, with most commendable promptness, as an Appendix to the Report of the Coast & Geodetic Survey for 1907, and the results seem of such importance, from the light thrown on the nature of the earth-movements which gave rise to this earthquake, that I have thought it desirable to make a detailed study of them from the geological point of view.
The area covered by the observations is not co-extensive with, but covers the most important part of, the seismic area; it extends from near Monterey, in the south, to Point Arena, in the north, and within this area all the points fixed by the triangulation which was carried out at various times between 1851 and 1899 were again fixed after the earthquake of 1906.
When the results came to be worked out, it was found that wherever triangulation of earlier date than about 1868 was connected up with triangulation of later date, the positions of the connecting points did not
On the Fossil Plants of the Waldershare and Fredville Series of the Kent Coalfield
Authors: Arber E. A. Newell 
Published: October 2009

At the present time, important series of coal-seams have been proved by means of borings in three localities in South-Eastern Kent. As apparently the lithological sequence, including the coal-seams, is quite distinct in each case, we may, as a temporary expedient until the structure of this concealed coalfield can be demonstrated, distinguish them as the Dover, Waldershare, and Fredville Series.
The Dover Series was the first discovered. In 1886, a boring was made at the site of the proposed Channel Tunnel on the foreshore at Shakespeare Cliff, rather more than a mile to the west of the Admiralty pier at Dover. The Coal-Measures were reached in 1890, at a depth of 1100 feet, and the boring subsequently penetrated to a depth of about 2270 feet, passing through thirteen seams of coal, varying from 1 to 4 feet in thickness. The Dover Series is essentially a thin-coal series, and sandstone-beds are comparatively numerous. For many years past attempts have been made to sink shafts, and to work the coals, on or near the site of the original borings, by the Kent Collieries, Limited, but hitherto with small success owing to difficulties in connexion with the inflowing water derived from the Mesozoic rocks. The fossil plants obtained from the original boring through the Dover Series were described by Prof. Zeiller in 1892, and will be further discussed here.
in 1904, a new company, the Kent Coal Concessions, Limited, with which several daughter companies and syndicates have more recently been associated, was formed
The Relations of the Nubian Sandstone and the Crystalline Rocks south of the Oasis of Kharga (Egypt)
Authors: Beadnell H. J. Llewellyn 
Published: October 2009

In the geological study of a country there is nothing of more importance than the mutual relations of the different rock-groups of which it is made up, and yet in Egypt it is perhaps more especially in regard to those relationships that our views have had from time to time to be materially altered. In particular, I may instance the relationships of the Eocene and Cretaceous Systems in different parts of the country, notably at Abu Roâsh, in the Eastern Desert, and in the Oases. The object of the present paper is to raise the question of the relation of the granites and associated crystalline rocks to the overlying sedimentary formations, a relationship of fundamental importance, and to put on record some observations bearing on the subject made during a brief examination of the country to the south of the Oasis of Kharga, undertaken with the primary object of eliciting certain information regarding the water-supply of that oasis. These observations appear to me to afford strong evidence that in this district the granites, in their present position at least, are younger than the overlying members of the Cretaceous Series.
The Crystalline Rocks south of the Oasis of Kharga.
That a solitary exposure of igneous rock exists at Jebel Abu Bayan, in the Libyan Desert south of the Oasis of Kharga, has long been known. Capt. Lyons, with reference to this locality, wrote :
‘The rock is a coarse-grained hornbleudic granite, with large crystals of pink orthoelase, and is apparently identical
On Labradorite - Norite with Porphyritic Labradorite Crystals: a Contribution to the Study of the Gabbroidal Eutectic
Authors: Vogt Johan H. L. 
Published: October 2009

The object of this paper is to contribute to the investigation, on a physico-chemical basis, of the sequence of crystallization in the gabbroidal eruptives.
The Lofoten and Vesteraal Islands on the northern coast of Norway (lat. 67° 50′ to 69° N.) constitute, as is well known, a petrographical province with a very considerable number of eruptives, among which orthoclase-plagioclase-rocks, especially monzonite and banatite, are the most frequent.
On one of the islands, Flakstadö, there is an area of labradorite-rock comparatively poor in ferromagnesian silicates and magnetite, besides labradorite-norite with somewhat larger quantities of the same. Under the name ‘labradorite-norite’ is denoted a rock which lies chemically and mineralogically on the boundary between labradorite-rock and norite.
The field-exposure of the labradorite-rock with the labradorite-norite has a length of sisteen and a half kilometres, a breadth averaging from two and a half to three and a half kilometres, and an area of about 50 square kilometres. To this must be added its continuation under the sea. At the northern margin, towards the Archæan in the neighbourhood of Napp Farm on Flakstadö, the labradorite-norite occurs with a porphyritic development, that is, with phenocrysts of labradorite-felspar, often of remarkably large dimensions. We will now examine this latter rock more closely.
The porphyritic labradorite-norite of Napp, like most of the rocks belonging to the eruptive province in question, generally shows little or no sign of pressure. It is in most places coarsely crystalline, with labradorite-phenocrysts measuring as much as 15 or 18 centimetres in length and from 6 to 8 in breadth. It has
On the Igneous and Associated Sedimentary Rocks of the Tourmakeady District, County Mayo
Authors: Gardiner Charles Irving , Reynolds Sidney Hugh 
Published: October 2009

Our
object in the present paper is to describe a series of igneous rocks associated with beds containing Ordovician fossils, and occupying a tract of country, having a width of about a mile, which extends along the western shore of Lough Mask from the hamlet of Derrindaffderg in the north to the neighbourhood of Tourmakeady in the south, a distance of about four and a half miles.

At the southern end of the area, on its eastern side, this igneous series of rocks is bounded by massive conglomerates; and rocks lithblogically similar, though probably of much later date, form the whole of the western boundary. Along most of the eastern border occur conglomerates and sandstones, to which we, following the Survey, shall refer as the basal beds of the Carboniferous, although they may be regarded with equal probability as representing the 01d Red Sandstone.
The surface is undulating, but the physical features are not striking—the ground never rising, in the area with which we deal, to a greater height than about 400 feet, or some 350 feet above Lough Mask. A number of streams traverse the district from west to east, and afford an excellent series of sections ; but, apart from these, exposures are almost everywhere numerous, this being partly due to the fact that the district is free from drift.
Considering the interesting and varied character of its geology, it is remarkable that comparatively little has hitherto been written about this area. In 1874, G. H. Kinahan,' in a paper
Note on some Geological Features observable at the Carpalla China-Clay Pit in the Parish of St. Stephen's, Cornwall
Authors: Collins Joseph Henry 
Published: October 2009

This clay-work is situated on the Burngullow branch of the Great Western Railway, about a mile and a half north-west of Burngullow Station, at an elevation of about 550 feet above sea-level.
The land slopes generally from the east towards a rather deep valley, the railway running from nearly south to north along the eastern edge of the valley, on a low embankment across two fields where the inclination is very gentle. About the middle of its length, the embankment is traversed from east to west by an accommodation-road, over which the line is carried by an arch of masonry. East of the railway and also on the southern portion of the west side, the ground has been very thoroughly explored by means of pits and shafts, while the northern portion of the west side is fully exposed by the great clay-excavation (the Carpalla clay-pit), now over 100 feet deep.
The surface-soil or ‘ meat-earth,’ generally almost black and of a peaty character, covers or has covered the whole estate to a depth of 6 inches or more. Beneath this is everywhere a ‘ growan’ 1 or stratum of subsoil, varying in depth from 2 up to 10 or 12 feet. On each side of the railway from the hedge marked NN on the accompanying plan (fig. 1, p. 156), as far as the accommodation-road above mentioned, this growan rests upon a stratified rock locally known as killas, which is here really a well-marked tourmaline-schist ; beyond the road, it
The Relation of the Ordovician and Silurian Rocks of Conway, North Wales
Authors: Elles Gertrude L. 
Published: October 2009

The area constituting the Conway District, for the present purpose, extends from the mountains of Penmaenbach and Dinas on the west, southwards as far as DerwendJg, and thence eastwards to the Conway River, thus including Conway Mountain, and the whole of the country lying immediately north, south-west, and south of the town of Conway itself. On the east side of the estuary there is also the area lying east, north-east, and south-east of the village of Deganwy.
The region has not hitherto been worked in any detail, wherefore the literature as a whole is scanty and the information somewhat unsatisfactory. The volcanic rocks have received the greatest share of attention, some of the rhyolites, and especially the nodular rhyolites, having been described by Prof. Bonney, Mr. Harker, Prof. Grenville Cole, and others; but the sedimentary rocks have rarely received more than a general notice.
The more important papers referring to the district are the following :—
(A) Stratigraphical.
Jukes, in his ‘ Letters,’ makes several references to the district; of these the most important statement seems to be that where he refers to Conway Castle as standing ‘on the very top of the Bala Beds, somewhere about where the Hirnant Limestone ought to be.’
Unfortunately, he afterwards accepted the view that the rock in question was the equivalent of the Bala Limestone. 1 In the light of recent work, his earlier opinion would seem to be more correct.
Prof. Lapworth, in his classical work on the ' Geological Distribution of
On the Sculptures of the Chalk Downs in Kent, Surrey, and Sussex
Authors: Clinch George 
Published: October 2009

The Author classifies the various forms of sculpture of the Chalk Downs under three heads, namely, (1) dry valleys of simple form, (2) dry valleys of complex form, and (3) wet valleys. He draws attention to the relatively small catchment-areas of the dry valleys, and to the large number of tributary valleys found in some districts, two points which he considers have not hitherto received entirely satisfactory explanation.
While accepting the view that frozen conditions in former times altered the drainage-system of the Chalk, he argues that the most potent excavating force was the frost itself, acting on Chalk saturated or highly charged with water. He points out the following peculiarities of dry Chalk valleys:—(1) the great size and breadth of the valleys in relation to their catchment-basins; (2) the ramifications of some of the valley-systems; and (3) the termination of many dry valleys just short of the crest of the Chalk Downs.
In order to account for these phenomena, the Author propounds the following theories:—

(1)
The chief part of the valley, during and after periods of low temperature, being occupied by a mass of ice, erosion of the Chalk would naturally be more active at the sides than in the bottom of the valley: lateral development and sometimes elaborate ramification being the result.

(2)
The diminution of the catchment-area, due to the cuttingback of the valley towards the highest level, would have the effect of removing one of the chief agents in the breaking-up of the Chalk, with the result that the valley would die out just short of the crest of the Chalk Downs.
A Contribution to the Petrography of the New Red Sandstone in the West of England
Authors: Thomas Herbert Henry 
Published: October 2009

I. Introduction.
In a former paper communicated to this Society I dealt with the mineralogical constitution of the great Pebble-Bed, as developed in Devon and Somerset. The results obtained encouraged me to undertake a similar study of the other members of the New Red Sandstone Series in that district ; and, in the following communication, I have endeavoured to point out the mineralogical and physical differences exhibited by the microscopic particles which form the finer portions of the deposits. The classification and subdivision of the New Red Sandstone Series in Devon and Somerset has gradually evolved from the labours of several geologists, and I propose to use those subdivisions which are now adopted by the Geological Survey.
The New Red Sandstone in the area under consideration may be divided as follows, commencing with the older beds :—
These subdivisions are founded solely on lithological characters, and therefore form the most natural basis for a petrographical study.
The Lower Breccias are well-developed, and have been examined on the south coast at Teignmouth and Dawlish, along the western side of the Exe estuary on the flanks of the Haldon Hills, in the Exeter district, and in the Crediton and Stogumber valleys. They usually consist of deep-red breccias, sands, and sandstones, most often loose and incoherent, but occasionally compacted into rocks of more solid character.
The Lower Sandstones, which for the most part occupy a position above the breecias, have been studied on each side of the Exe estuary, in the vale of
On the Boulders of the Cambridge Drift: their Distribution and Origin
Authors: Rastall Robert Heron , Romanes James 
Published: October 2009

I. Introduction.
The origin and distribution of the boulders of the Glacial Drift of Cambridgeshire and the adjoining countries is a subject of great interest on which hitherto little work has been done. Although much has been written on the Glacial deposits of this district as a whole, little attempt has been made to examine in detail the types of rock represented in the Boulder-Clay and to trace them to their sources. During the last seven or eight years a large amount of material has been collected, both by the members of the Sedgwick Club and by other independent workers. A brief account of some of the results obtained up to that time was given by Mr. Fearnsides in the official hand-book compiled for the Cambridge meeting of the British Association in 1904, and a short paper entitled ‘On Boulders from the Cambridge Drift, collected by the Sedgwick Club’ was published in the same year by one of the present authors. Since that date much new material has been collected, and the whole has now come into our hands. The additional evidence thus made available, shows that the conclusions set tbrth in the previous publications can be considerably extended.
The total number of boulders collected now amounts to many hundreds ; and, as naturally would be expected, a great number of them, perhaps the majority, are of uncertain origin, since it, is clear that the field of derivation is a very wide one. However, a large number of rock-types have
On Overthrusts at Tintagel, North Cornwall
Authors: Dewey Henry 
Published: October 2009

I. Introduction.
On mapping the country to the north of Bodmin Moor for the Geological Survey, it was found that the slate-rocks, as noted by Mr. John Parkinson, are separable into several well-marked lithological types. These types are of widespread occurrence, and strike across the country in parallel zones in a general west-north-westerly and east-south-easterly direction with a constant dip to the north-north-east.
But, although this stratigraphical succession occurs over so wide an area, it apparently broke down in the Tintagel district, where a repetition of the strata was found near the coast. Subsequent investigation, however, proved the repetition to be due to overthrusts from the west-north-west. With the district affected by overthrusts I propose to deal in the present paper.
Several observers have written about the geology of Tintagel, but as none of them interpreted the structure, it, is only ,ecessary to give references to their papers in the following list :—
II. Description of the Area covered by the Map (Pl. XIII).
The area represented on the map covers about 5 square miles, with about 4 miles of coast-line. The district forms a plateau ending off in cliffs which are between 300 and 400 feet high. A portion of a still higher plateau rising to 600 feet occurs in the south-eastern corner of the map. Two small streams dissect the lower plateau, the one on the north forming the Rocky Valley ; and the other, on the west, the Trevena Valley. The whole area forms a land-mass which
Glacial Erosion in North Wales
Authors: Davis William Morris 
Published: October 2009

I. The Form of Snowdon.
An excursion around Snowdon, the highest of the Welsh mountains, in September, 1907, led me to the conclusion that a large-featured, round-shouldered, full-bodied mountain of pre-Glaeial time had been converted by erosion during the Glacial Period—and chiefly by glacial erosion—into the sharp-featured, hollow-chested, narrow spurred mountain of to-day. Or, to phrase it in somewhat more technical style, that a body of ancient slates, felsites, and volcanic ashes, greatly deformed in Palæozoic time and greatly worn down in successive cycles of Palæozoic, Mesozoic and Tertiary erosion, was reduced before the Glacial Period began to subdued mountain-form with dome-like central summit, large rounded spurs, and smooth waste-covered slopes, and with mature valleys drained by steady flowing streams which branched delicately headwards, with steepening slope, and which joined each other mouthwards in the accordant fashion that so systematically characterizes the drainage of all normally subdued mountain-masses. Also that this full-bodied mass was transformed during the Glacial Period, chiefly by the glacial excavation of valley-head cwms and by the glacial widening and deepening of the valleys themselves, irate a sharp central peak, which gives forth acutely serrated ridges between wide amlphi theatres: the serrated ridges changing into broad-spreading spurs as they are followed outwards ; the wide amphitheatres, backed by high rocky cliffs, opening by great rock-steps to irregularly deepened trough-like valleys, with oversteepened, undissected sides, sometimes smooth, sometimes of a peculiarly roughened slope; the smaller lateral valleys hanging in strikingly discordant fashion over the floors of the larger
The Nephrite and Magnesian Rocks of the South Island of New Zealand
Authors: Finlayson Alexander Moncrieff 
Published: October 2009

Ever since Hochstetter's work on the olivine-rock of the Dun Mountain, and on the New Zealand nephrite or ‘greenstone,’ the rocks of the ‘magnesian belt’ of the South Island of New Zealand have had an absorbing interest for students of that district. The term ‘magnesian belt’ is here used to denote those peridotites and serpentines that have hitherto been frequently referred to by the names ‘serpentine-belt’ and ‘mineral-belt,’ Until recent years, however, the occurrence and nature of the various exposures which comprise this most interesting and significant petrographic province have remained rather obscure, owing to the rugged nature of the country and the inaccessibility of the chief localities.
In this paper is given a general account of the peridotite- and serpentine-rocks of the South Island and a discussion of the nature and origin of New Zealand nephrite. Those analyses which are not attributed to others are my own work, and were made in the geological laboratory of the Imperial College of Science & Technology, South Kensington.
II. The Peridotites and Serpentines.
General Occurence and Relations.
Occurrence.—The position of the known outcrops is indicated on the map accompanying this paper (fig. 1, p. 352). The magnesian belt, as generally understood, first appears as a group of serpeatines and peridotites extending from D'Urville Island in a south-westerly direction for some miles past the town of Nelson. Serpentines have also been observed in the Buller basin ; and still farther south, in the western foothills of the Southern Alps, occur the disconnected sills
Some Notes on the Neighbourhood of the Victoria Falls (Rhodesia)
Authors: Codrington Thomas 
Published: October 2009

A stay of nearly four months at Government House, Livingstone, in 1908, afforded me the opportunity of making observations at leisure and gathering the information which is embodied in the following paper.
Livingstone, now the seat of the Administration of North-Western Rhodesia, is within easy reach of the Zambesi at the boathouse 2½ miles above the Victoria Falls. From that point all parts of the river are accessible as far as the rapids, 5 miles farther up, and downwards nearly to the Falls, which can also be reached by railway. Much time was passed on the river, and every facility was afforded me for visiting both sides of the Zambesi for some miles above and below the Falls, and for seeing the valley of the Maramba for some 6 miles upwards from its confluence with the Zambesi. I had the advantage of Mr. G. W. Lamplugh's recent papers on the Geology of the Zambesi Basin, and on the Occurrence of Stone-Implements around the Victoria Falls, and also of access to maps, plans, levels, etc., prepared by the engineers of the British South Africa Company, to whom, and many others, my thanks are due for help and information.
In bringing forward these observations, it is not necessary to refer to what has previously been written, as the literature has been recapitulated as lately as 1907 in Mr. Lamplugh's paper above mentioned. With what is said in that paper about the gorge below the Falls I entirely agree, and to it I