bluuebunny/crossref_metadata_2025 huggingface dataset:
The Petrography of the Blea Wyke Series
Authors: Rastall R. H. , Hemingway J. E.
Published: May 2009

The general results which have accrued from this investigation may be summarized as follows: the shaly type of Liassic sedimentation with much pyrite, indicating a quiet sea with abundant sulphur compounds, gradually gave place to a regular and at first fairly steady shallowing of the water with, somewhat later, occasional incursions of strong currents bringing pebbles and broken fossils from an area undergoing active erosion. At the same time the amount of iron introduced, both in solution and in the form of derived ooliths, increased steadily, culminating in the siliceous oolite of the Dogger, which is essentially similar to the rocks composing this formation to the west and north-west.
Some Minor Intrusions of Glen Shee, Perthshire
Authors: Williamson W. O.
Published: May 2009

Some additional data are given regarding the “newer” intrusions of an area of which the main petrological features have been described elsewhere. The intrusions are:—
(1) Aplites, pegmatites, quartz-veins, granodiorite porphyries, and biotite-granodiorites in or around the Newer Diorite. (2) A “porphyry” contaminated by cordieritic hornfels and having “clouded ” plagioclase “phenocrysts ”. Evidence is given that the “phenocrysts” have xenocrystic cores. (3) Quartz-felsites with cordierite, andalusite, and garnet, and granodiorite-porphyries, lying between the Newer Diorite and its roof of Ben Lawers Schist. The granodiorite-porphyries post-date the Diorite but the age of the quartz-felsites is uncertain. Contamination, and mechanical and chemical alteration, of the quartz-felsites are recorded. (4) Newer quartz-felspar-porphyries and lamprophyres, not obviously associated with the Newer Diorite.
Earth-Movements, Ice Ages, and Faunas
Authors: Hopwood A. Tindell
Published: May 2009

Nearly thirty years ago Penck and Brückner published Die Alpen im Eiszeitalter, which has moulded the views of European glacialists over since. It is the basic authority for the theory that there were four glaciations—the familiar Günz, Mindel, Riss, and Würm—separated by three warm interglacial periods. This theory has been further elaborated to such an extent that Zeuner (1935) lists some eight or nine glacial phases with a corresponding number of intervening warm phases.
The Idea of Contrasted Differentiation
Authors: Holmes Arthur
Published: May 2009

As early as 1915, it was made clear by Bowen that, given continuous separation of crystals from the successive residual liquids of a consolidating magma which was initially basaltic in composition, the inevitable result would be a gabbroic rock in depth, a granitic one above, and “various intermediate types in the intermediate layers”. As a necessary condition to the evolution of a magmatic residuum of granitic composition, this process of progressive crystallization differentiation involves the generation of intermediate rock-types from residual liquids of intermediate composition. Certain investigators, however, led by the authors of the Mull memoir (1924), have entirely overlooked the necessity of this condition. Faced with the association of contrasted acid and basic rocks, which is a conspicuous characteristic of many continental central complexes, they have attempted to account for the facts by introducing a modified conception of crystallization differentiation for which Nockolds has recently proposed the name contrasted differentiation. According to this conception, the residual liquid of consolidating basaltic magma is of granitic composition and can be separated in bulk from a crystalline gabbroic phase.
On a Collection of Raised Beach Fossils from Spitsbergen
Authors: Elton C. S. , Baden-Powell D. F. W.
Published: May 2009

LARGE collections of material have been brought back by numerous Arctic Expeditions, and, as many writers have pointed out, much of this raised beach material proves changes of climatic and other ecological conditions during Quaternary times. Before correlation of Quaternary deposits in Spitsbergen and other Arctic lands can become at all certain, it is essential that as many detailed contributions as possible should be made to our total collection of facts.
The Avonian Inlier at Upper Vobster (Somerset)
Authors: Welch F. B. A.
Published: May 2009

THE inlier of Carboniferous Limestone, situate within the Coal Measure area at Upper Vobster, was the subject of much controversy in the past. It was not, however, until 1912 that Dr. T. F. Sibly settled this vexed question, and showed that the inlier was a mass of Carboniferous Limestone and “Millstone Grit” superimposed upon folded Coal Measures by thrust-faulting. His paper contains a very accurate map showing the extent of the quarries and strata exposed at the time: the latter now unfortunately having been removed by further quarrying.
An Astraeiform Coral from Central Japan
Authors: Hayasaka Ichiro
Published: May 2009

SINCE the publication of my paper on the fauna of the Anthracolithic Limestone of Oomi-mura, Province of Echigo, Central Japan, I have added to my collection fresh material from this locality, collected either by myself or by others. Among this is an astraeiform coral to which I wish to draw attention since such corals are everywhere uncommon in the Carboniferous and, as far as Japan is concerned, is the first to be recorded. The specimen is only a small fragment, its polished transverse surface measuring not more than 2 cm. by 2 cm. Unfortunately the coral is in an unsatisfactory state of preservation so that its structural details are difficult to decipher. However, from a careful examination of the polished surface and of thin sections cut from the coral I am inclined to regard it as a species of Orionastraea Smith, a genus which hitherto has only been known to occur in the Carboniferous rocks of the British Isles.
Algal Limestones from Gigoomgan, Queensland
Authors: Richards H. C. , Bryan W. H.
Published: May 2009

THIS paper describes the occurrence in Queensland of a large mass of limestone of late Palaeozoic age made up almost entirely of the microscopic remains of calcareous algae.
The Scottish Species of Allagecrinus
Authors: Wright James
Published: May 2009

SINCE the publication of Carpenter and Etheridge’s paper in 1881, in which the characters of Allagecrinus were first made known to us, few records have been noted of any other Scottish specimens belonging to the genus. The specimens figured and described by the above authors were obtained from shale collected by the late Mr. Bennie of the Scottish Geological Survey, the localities being Carlops; Catcraig, near Dunbar; Burlage, near Dunbar; Whitebaulks, near Linlithgow; Addiewell and Roscobie, all in what may be called the East of Scotland; together with a few from Howood and Carluke in the West of Scotland.
On an Orbicular Diorite from the Island of Alderney
Authors: Nockolds S. R.
Published: May 2009

WHILST studying the Bibette Head Granite, the writer had occasion to devote a certain amount of attention to the rocks with which it is in contact. In the region under consideration, these are essentially of dioritic type. The Orbicular Diorite was first found in a small embayment forming part of the west side of Corblet's Bay. It was found later in a less well developed fashion, at Saye Bay. It is quite possible that extended search would prove the presence of more. For the most part the orbicules are widely scattered, but a boulder was found at the Corblet's Bay locality which shows several associated with inclusions of a more basic rock. This boulder is now in the Sedgwick Museum, Cambridge.
Reinterpretation of the Bray Series at Howth, Irish Free State
Authors: Lamont Archie
Published: May 2009

Among other parallels to the structures which he regarded as “crush-conglomerates” in the Manx slates, G. W. Lamplugh (1895, 586–7) mentions beds with isolated fragments in the Bray Series, at Howth, Co. Dublin. The age of this Series of slates and quartzites is rather conjectural. Fossil evidence, founded on such forms asOldhamia, though supplemented by W. J. Kyan and T. Hallissy, who suggest Middle Cambrian (1912, 249), is inconclusive. More recently, E. Greenly proposes a pre-Cambrian age (1919, 896). The alternating (or greywacke) type of sedimentation seen in the beds recurs many times during Dalradian, Cambrian, Ordovician, and Silurian. Two schools in the interpretation of the Series have to be considered. The older school, with J. Kelly (1853, 240, 253–262) and G. H. Kinahan (1878, 12, 14) as its adherents, ascribed the fragmentation in the shaly beds to volcanic agencies, and, since they failed to distinguish cleavage from bedding, regarded many of the quartzites as intrusive. The younger school, including A. McHenry and W. W. Watts (1898, 17) and Lamplugh (1903, 6), described the breccias as produced by friction during regional earth-movements. The latter, as W. J. Sollas puts it (1893, 98), possibly extended from post-Ordovician to post-Carboniferous. While the effect of later crushing and faulting must not be overlooked, it seems necessary i n the light of recent work by E. B. Bailey (1930, 86–90), Bailey and J. Weir (1932, 429–458), and S. M. K. Henderson (1935, 487–509), t o invoke probable seismicity and contemporaneous slumping to explain the alternating beds and associated shaly breccia. A new suggestion will be advanced regarding the quartzites.
A Sandstone with Fluorspar Cement and other Sandstones from West Cumberland
Authors: Lewis H. P.
Published: May 2009

SOME time ago Mr. Charles Edmonds provided me with a number of sandstones of Carboniferous age from West Cumberland to compare with the sandstones of the Peel Series in the Isle of Man. These specimens proved to have an interest peculiar to themselves which it is the purpose of this note to describe.
Notes on the Species Illaenus bowmanni Salter
Authors: Cowper Reed F. R.
Published: May 2009

THERE has been considerable uncertainty about the true characters of the species Illaenus bowmanni Salter, and many foreign palaeontologists have consequently found it difficult to institute a close comparison of it with other species and have suspected its composite nature. As Holm and Warburg have remarked, the species is badly characterized, and some important critical features, such as the shape of the caudal fascia, are ill-defined or not clearly described in the definitions or well represented in the figures. The poorness of the specimens is largely accountable for these omissions. A recent detailed investigation which the author has been enabled to make of the specimens used by Salter, Portlock, and McCoy in drawing up a definition of the species, together with the examination of many other specimens ascribed to it from the original and other localities, throws some useful light on the subject and helps to clear up some of the obscure points, but it also shows that most of the earlier and current synonymies and references which have been published from time to time are untrustworthy and inaccurate.
The Influence of Climate and Topography in the Formation and Distribution of Products of Weathering
Authors: Woolnough W. G.
Published: May 2009

For many years the writer has been specially interested in the variations apparent in the processes of weathering of rocks under different climatic and physiographic conditions, and has made several attempts to explain such features. Of these published attempts the most detailed took the form of a Presidential Address to the Royal Society of New South Wales in 1927. Certain portions of the argument were repeated in Economic Geology, but the regional aspects of the question were omitted.
The Grading of Dune Sand by Wind
Authors: Barrett W. H.
Published: May 2009

The samples to be described in this paper were taken from a small bay on the north coast of Sutherland called Traigh Allt Chailgeag on the Ordnance map. This bay is about three miles east of Durness, and one mile west of the mouth of L. Eireboll. It is eroded in gneiss, and is fed by a small stream at either end of the bay.
The Heavy Mineral Suites and Correlation of the Granites of Northern Brittany, the Channel Islands, and the Cotentin
Authors: Groves A. W.
Published: May 2009

The area studied includes the majority of the main granite masses north of the belt of Ordovician and Silurian rocks running eastwards from Quimper to around Vitré and Laval. The heavy minerals of the Channel Islands granites have already been described by the writer (1). In the present paper the work is extended to the northern half of Finistère, and the greater part of the Côtes-du-Nord, Ille-et-Vilaine, and Manche. It is confined for the most part to the granites, and comparisons are made with those of the Channel Islands in an endeavour to obtain more definite evidence as to the age of the Jersey “Newer” Granites.
The Age of the Connemara Schists and of their Metamorphism
Authors: Wager L. R. , Andrew G.
Published: May 2009

In Connemara and South Mayo, three main rock groups have been distinguished. The first group, largely developed in South Mayo (see sketch-map), consists of slates, phyllites, grits, conglomerates and thin limestones, and, although these rocks are much cleaved, sufficient fossils have been found to prove that they vary in age from Arenig to Ludlow. The second group of rocks, occurring principally in northern Connemara, consists essentially of quartzites, limestones and schists, and in this group fossils have not been found. In the pelitic schists of this group, biotite, garnet, staurolite and fibrous sillimanite are of widespread occurrence, proving that the group as a whole is in a state of medium to high grade regional metamorphism. We propose that the term Connemara Schists, which has previously only been used vaguely, should be restricted to this group. The third group, occurring in Southern Connemara, is a gneissic series which was tentatively correlated with the Lewisian Gneiss by early workers, and which is indeed remarkably similar to it in general appearance. Later work by Callaway (1887) and McHenry (1903) has, however, shown that these gneisses are not overlain unconformably by the Connemara schists, but are orthogneisses intrusive into them. Their age, therefore, relative to the Connemara Schists, is not in doubt.
The Action of Colloids in Precipitating Fine-Grained Sediments
Authors: Boswell P. G. H.
Published: May 2009

With certain well-known exceptions, ancient sandy and clayey sediments do little more than approach a condition of uniform grain-size. The so-called clays, silts and sands, and their consolidated equivalents, the mudstones, shales, silt-stones and sandstones, receive their appellation in most cases from the dominant grade present. Actually they consist of a mixture of particles, distributed over a considerable range of grain-size, in which the dominant grade, especially in the case of the finer deposits, often amounts to less than 50 per cent of the whole.
The Centenary of Lyell's “Principles of Geology”
Authors: Lake Philip
Published: May 2009

In the literature of geology there is no book that has exercised a more lasting influence on the science than Lyell's Principles of Geology, the first volume of which was published a hundred years ago. The twelfth and last edition appeared in 1875, some months after the author's death. The active life of the work thus extended over some fifty or sixty years, while indirectly its influence still survives.
Notes on the Petrology of the Bufumbira Volcanic Rocks of Uganda
Authors: Simmons W. C.
Published: May 2009

In view of the probability that there is likely to be some little delay in publishing the official Memoir on the Bufumbira volcanic rocks, which is in course of preparation by Mr. A. D. Combe and the writer, with, we hope, collaboration with authorities in England, permission has been given to publish a short summary of the results so far obtained in the investigation of these rocks. Mr. Combe has made a careful geological survey of the ground and has separated on his map forty-nine flows from nearly forty different centres situated at the south-west corner of the Uganda Protectorate. The remainder of this large volcanic field lies in the Belgian Congo to the west and south, and though all of those volcanoes, several of which are still active, have been visited by geologists and specimens of the rocks obtained, no very detailed field-work has been published on them, either by us or any other observers up to the present time; so far as is known to the writer.
An Igneous Conglomerate at Woolley, Devon
Authors: Groves A. W.
Published: May 2009

On Sheet 339 of the One Inch (New Series) Map of the Geological Survey there is marked at Woolley, within the metamorphic aureole of the Dartmoor granite, between Bovey Tracey and Lust-leigh, a patch of “Permian” rocks. Upon inquiry the Director of the Geological Survey, Sir John Flett, informed me that this was an error and should have been marked as “Felsite”. As the rock constituting the outcrop presents unusual features and is very different from an ordinary felsite I feel that a description of it should be placed on record. Moreover, it appears to be a good example of a rather uncommon rock type.
The Moon and Radioactivity
Authors: Forbes V. S.
Published: May 2009

In a study of the surface features of our satellite one is immediately struck by the remarkable sharpness and freshness which most of those features exhibit. Further, one is impressed by the fact that evidences of compressive action are in the minority, whereas the moon's crust shows clearly innumerable clefts, rifts, and fractures pointing to an extensional tendency of its outer envelope. This is hardly in accordance with our ideas of the appearance of a sphere which has lost all its heat; everywhere it should show signs of intense contraction, and arcuate mountain ranges should be more frequent than upon the face of the earth.
Dendroseris n.g. and other Corals from Trinidad
Authors: Gregory J. W.
Published: May 2009

Mr. J. V. Harrison has entrusted me with the description of some fossil corals which be has recently collected in Trinidad. They include one remarkable coral which at first sight appeared to be Paleozoic, as its branches had a laminar structure resembling specimens of the Devonian Pachypora cervicornis in which the section has cut bands of corallites at different angles. Examination with a lens at once showed that the coral was septate, and that the resemblance to Pachypora was delusive.
Notes on the Millstone Grit of the North Crop of the South Wales Coalfield
Authors: Evans D. G. , Jones R. O.
Published: May 2009

The precise age of the Millstone Grit of South Wales has been in doubt for some years. Although it has been shown to be of Upper Carboniferous age, it has been uncertain whether the whole of the earliest part of the Upper Carboniferous is represented by deposits in southern Britain. Some part of the Millstone Grit of Pembrokeshire has been regarded, on the basis of its flora, as of Middle Coal Measure or Yorkian age (Goode, 1913, p. 272). Similar conclusions have been reached by Dr. R. Crookall concerning part of the Millstone Grit of Somerset (1925, p. 403). As yet, the flora characteristic of the Lanarkian of northern Britain has not been proved to be present in South Wales and elsewhere in south Britain. On the other hand, it has been argued that the absence of a Lanarkian flora does not necessarily imply an important break in the sequence, since recent work on the lamellibranch fauna of various British coalfields points to the conclusion that the lowest part of the Lower Coal Series of South Wales is of approximately the same age as the Lower Coal Measures of northern England (Davies and Trueman, 1927, p. 253).
The Gneiss of Inishtrahull, County Donegal
Authors: McCallien William J.
Published: May 2009

The previous literature on the pre-Cambrian rocks of Ireland is considerable in amount. The views of the early workers are briefly referred to in the Handbook of the Geology of Ireland, by G. A. Cole and T. Hallissy, published in 1924. This work doubtless expresses the opinion of Irish geologists of the present day.
The Petrology of some Yorkshire Boulder Clays
Authors: Raistrick A.
Published: May 2009

One of the most imposing and best known exposures of glacial deposits in the north of England is the line of high cliffs along the Yorkshire coast, between Patrington and Withernsea, the highest point of the cliffs being at Dimlington Beacon. Here 140 feet of glacial material is exposed in the cliff face and the foreshore is entirely of boulder clay, the base of the deposits being a long way below sea-level. The work of this paper relates to the clays and sands in this cliff exposure. The deposits are easily distinguished as being of three varieties; at the base and along the foreshore, a dark leaden grey to black, tough boulder clay, including lenticles of sand frequently containing shell fragments; this is succeeded by a thick clay of rich purple or red colour, with noticeably more contained boulders, and near the top, much included sand in lenticles, passing into a bed of pure sand; the highest part of the cliff is of earthy clay, foxy red in colour, and with relatively few boulders. These are respectively the Basement clay, the Purple clay, and the Hessle clay. Between the Basement clay and the Purple, and at the top of the Purple clay, there are beds of sand a few feet thick; these are not to be seen at all parts of the coast, but are generally present in the highest sections. Fig. 1 is a vertical section of the Dimlington cliff, and the Roman numerals indicate the specimens petrologically examined.
On Melilite as a Product of Interaction of Limestone and Basaltic Liquid
Authors: Tilley C. E.
Published: May 2009

The melilite described below is an abundant constituent of a zone of reaction between dolerite and Chalk at the intrusion of Scawt Hill, Co. Antrim, Ireland. The melilite occurs both in the hybrid rock formed by assimilation of carbonate and as a constituent of the exomorphic contact zone. In the latter it is associated with spurrite, Ca2SiO4 (larnite), merwinite, spinel, and calcite. The following description applies solely, however, to the melilite of the hybrid rock.
The Occurrence of Reticuloceras reticulatum in the Culm of North Devon
Authors: Moore E. W. J.
Published: May 2009

Reticuloceras Reticulatum is the typical goniatite in the topmost beds of the Sabden Shales of Lancashire. This form is known from the Exeter district (Collins and Crick, Q.J.G.S., vol. lxvii, 1911, p. 393), but apparently the only recorded occurrence of this form in North Devon is by Wheelton Hind, who, in the report of a lecture on the correlation of the rocks in North Devon with other areas, is stated to have said, “Glyphioceras reticulatum has been obtained by Mr. Inkermann Rogers” (Proc. Geol. Ass., vol. xxi, part viii, p. 463). In the summer of 1928, Mr. Rogers was good enough to take the writer over the ground at Ilsey Beach, Lower Yelland, where he had obtained the specimen in question. The beds on this beach contain Goniatites spiralis and other goniatites, but not R. reticulatum. Inquiries at the British Museum (Natural History) elicited the information that no R. reticulatum from Devon was in the Hind Collection. As the specimen cannot be traced, confirmation is impossible. Its identity with R. reticulatum, however, is manifestly erroneous, owing to its association with G. spiralis, and with the lamellibranch, Posidonomya becheri, forms which do not survive to the top of the Bowland Shales of Lancashire.
On an Inverted Mass of Upper Cretaceous Strata near Leighton Buzzard, Bedfordshire; and on an Overlap of the Upper Gault in that Neighbourhood
Authors: Kitchin F. L. , Pringle J.
Published: May 2009

WE owe to Mr. Lamplugh a description of the lowest beds of the Gault and their junction with the Lower Greensand, as seen in sand-pits on the south side of Leighton Buzzard. Mr. Lamplugh proved the presence of the fauna of the mammillatus zone and found that the fossils preserved in the gritty phosphatic nodules of the lowest bed above the false-bedded sands include Douvilleiceras mammillatum (Schloth.) and the characteristic Desmoceras usually associated with it.
A Curious Fossil Charophyte Fruit
Authors: Groves James
Published: May 2009

THROUGH the kindness of Mr. Henry Woods, I have had the opportunity of examining three blocks of limestone belonging to the Sedgwick Museum at Cambridge, which were collected by the late E. B. Tawney, from the “Chara Bed”, Étage Oeningien, Upper Miocene, at Locle, Jura (Canton Neuchatel, Switzerland). The blocks contain a number of the remains of fruits of a species of Charophyte, which present a feature I had not hitherto observed, and to which I think attention may advantageously be drawn. Before describing this peculiarity, however, it will be desirable to say something as to the conditions of preservation in which such bodies are usually found.
Notes on Lateritization in Sierra Leone
Authors: Dixey F.
Published: May 2009

1. Lateritization has been found to affect a variety of rocks in Sierra Leone, including norite, granitic rocks, and detrital deposits.

2. The norite of Sierra Leone is not deeply lateritized except in highly jointed areas or in certain bands readily susceptible to the alteration. It yields a gibbsitic laterite. A core of unaltered norite is enclosed in a light-coloured halo (“zone of leaching” of Professor Lacroix), which passes gradually into a red-brown laterite (“zone of concretion”). The transition from core to laterite is a rapid one. The minerals of the norite are attacked in the following order: felspar, diallage, hypersthene, magnetite (titanomagnetite).

3. Norite containing only a small quantity of disseminated magnetite is less readily lateritized than norite containing a moderate amount. Where, however, the norite includes an unusually high proportion, as in the streaks of magnetite, lateritization proceeds very slowly.

4. The granitic rocks of the Protectorate are frequently lateritized to a depth of 15 feet, and sometimes even to 30 feet. Nevertheless laterite is only slightly developed in the inselberg mountain districts of the northern part of the country. Lateritization of granitic rocks proceeds as follows: the rocks decompose into a white kaolinitic product, which passes into.brown lateritic clay (“zone of leaching”); this lateritic clay then develops into laterite (“zone of concretion”). There is a progressive change from the unaltered rock to the laterite crust, the granitic rocks in this respect presenting a marked contrast to the basic rocks.

5. Lateritization affects detrital deposits also, particularly the Pleistocene sands and clays of the coastal plain. The phenomenon is most pronounced in the felspathic sands and diminishes in the more argillaceous beds until it is practically non-existent in pure clay. The typical lateritite is a red-brown scoriaceous rock, moderately hard, and in the hand specimen coarsely porous. It forms a crust about 10 feet thick at the top of the Pleistocene beds. This lateritite is indistinguishable from the laterite derived from other rocks.

6. The scoriaceous laterite (lateritite) was produced by the growth and ultimate coalescence of numerous small ferruginous concretions, followed by the removal of the soft material between the concretions.

7. The laterite formed from detrital deposits passes locally into lateritic iron-ore by increase in the percentage of iron oxide. Such iron-ores are well developed along the inner margin of the coastal plain encircling the colony, and occur principally in the neighbourhood of Devil Hole, near Waterloo. They were derived originally from the titanomagnetite which enters largely into the composition of the norite, and they are consequently very rich in titanium.

8. Lateritization is frequently an important factor in the production of caves and subterranean channels, owing to the ease with which the unconsolidated material is removed from beneath the thick hard crust of laterite.
Notes on the Fauna of the Lower Devonian Beds of Torquay
Authors: Cowper Reed F. R.
Published: May 2009

OUR knowledge of the fauna contained in the Lower Devonian beds of England is extremely imperfect and unsatisfactory, partly owing to the scantiness of the material which has been collected, and partly to the poor preservation of most of the fossils themselves. The lists of genera and species given in the Survey memoir (Explan. Sheet 350) dealing with the Torquay district are not extensive, and in many cases the determination of the species or even the genera is open to doubt. Correlation in detail with the well-established and richly fossiliferous Lower Devonian of the Continent is almost impossible in such circumstances, but Kayser in 1889, on the strength of the palæontological evidence which he obtained on the spot, correlated the beds at Meadfoot with the Lower Coblenzian. The fossils which he collected and identified from this locality were the following Rhenish species: Zaphrentis oolitica, Rhynchonella daleidensis, Chonetes sarcinulata, Spirifera hysterica, Sp. paradoxa, Strophomena cf. Murchisoni, Pterinea costata.
Frost Action in Superficial Deposits, Iceland
Authors: Hawkes Leonard
Published: May 2009

The object of this article is to draw attention to the patterns found in surface deposits of Iceland which are attributable to frost action and alternating frost and thaw, and to point out that such structures may be preserved in sediments, as valuable indicators of ancient climates.
On a Specimen of Fossil Wood from King's Arms Pit, Tiptree, Essex
Authors: Edwards W. N.
Published: May 2009

An examination of sections of the silicified wood from the King's Arms Pit, Tiptree, revealed at once that the structure was of the Dadoxylon type, and the absence of growth rings strongly suggested affinity with the Palaeozoic woods included in that genus, many of which are allied to Cordaites rather than to the araucarians. Among known silicified woods, a close comparison was possible only with those from the Corley (Enville) Group of the Midlands, now regarded as probably Upper Carboniferous, and not Permian.
The Mudstreams (“Lahars”) of Gunong Keloet in Java
Authors: Scrivenor J. B.
Published: May 2009

Some time ago I was asked, in connection with a question regarding the Dwyka conglomerate, to say if any of the volcanic deposits of Java in any way resemble a glacial deposit. As I was in Java from 12th May to 6th June as a Member of the Fourth Pacific Science Congress, and travelled from Batavia to Soerabaya via Buitenzorg, Bandoeng, Garoet, Koeningan, Loh Ulu, Jocja, Kediri, and the Tengger Mountains, as well as going to Krakatau, I had a good opportunity of replying to the question, but it must be understood that this note is not intended as a contribution to literature on the Dwyka conglomerate, which I have never seen, but purely as an answer to the query “are there any volcanic deposits in Java resembling glacial deposits ?” The reply briefly is that such deposits do exist, namely the “mudstream-deposits” of Gunong Keloet, near Kediri.
Contributions to the Geology of Cyprus
Authors: Reed F. R. Cowper
Published: May 2009

The general features of the geology of Cyprus have been established by the work of Gaudry and of Bellamy and Jukes-Browne (1), (2); while the later researches of Professors Cullis and Edge (3) have added much to our knowledge. But in every case it has been recognized that many questions were left unsettled and many details remained to be filled in. In this connection the importance of the geological work which has been done during recent years on the neighbouring coasts of Asia Minor and Syria has been some what overlooked, though in view of the close tectonic relations between the mainland and Cyprus it deserves particular attention.
Some Mesozoic and Tertiary Igneous Rocks from Portuguese East Africa
Authors: Mennell F. P.
Published: May 2009

The very interesting igneous rocks of the Mozambique Company's territory have not had much attention paid to them in the past, though some of them were noticed in the first paper dealing with the Karroo beds near Tete, that by Lapierre. That writer was in advance of some subsequent observers in his recognition of the peculiar character of the Lupata lavas: so far, indeed, have some others been from this that the various geologists working in the Tete district have actually been accustomed to call the Karroo basalts the “Lupata Volcanics”, as is done in the most recent paper referring to that area. The age of the basalts was demonstrated by the writer in some notes contributed to this Magazine in 1922, and to establish this it was necessary to discuss the position of the Lupata lavas. Messrs. Teale and Campbell Smith subsequently published the first reliable petrographical descriptions of some specimens previously collected by the former, and the present paper is intended to supplement by further field and petrographical notes the valuable work of Dr. Teale, who has long since sought pastures new. It may be mentioned that one of the chief features of the area is the way in which the various igneous rocks are sometimes intermixed. This is a leading factor in contributing to the uncertainty which surrounds the dating of some of the intrusives. Thus a large number of intrusions of various kinds traverse the Karroo basalts and these are undoubtedly of two and perhaps of three different periods. Faulting and overlaps also cause further complications, as may be seen in the small sedimentary area near Mutarara, where Tertiary, Cretaceous, and Karroo volcanics occur closely associated.
Notes on Some Analyses of Egyptian Metamorphic Rocks (Schists)
Authors: Hume W. F. , Harwood H. F. , Riley H. L.
Published: May 2009

This paper gives the results of a series of analyses of typical schists occurring in the Eastern Desert of Egypt. So far as we are aware, no study of this group of metamorphic rocks has as yet been undertaken as regards Egypt itself. Yet this method of attack is essential if any knowledge is to be obtained, not only of their structure and composition, but also of their origin. It must not be forgotten that schists occupy vast areas in south-eastern Egypt, and are also present in Sinai; also among them are included varieties derived from igneous and volcanic rocks as well as from ancient sediments.
On the Occurrence of Iron-rich Cordierite in Aberdeenshire
Authors: Read H. H.
Published: May 2009

In my account of the petrology of the Arnage district of Aberdeenshire, there appeared a description, figure, and analysis of a cordierite-spinel-hornfels from Gallowhill Brae, Arnage. This rock is composed almost entirely of cordierite, with only an accessory amount of spinel, biotite, and plagioclase. On the assumption that the analysis represented the composition of the sliced material, it was pointed out that in the cordierite of this rock, iron-oxides must replace much of the alumina and magnesia of normal cordierite.
A Monticellite-Nepheline-Basalt from Tasmania: a correction to mineral data
Authors: Tilley C. E.
Published: May 2009

F. P. Paul described in 1906 (T.M.P.M., vol. 25, p. 309) a nepheline-eudialite-basalt from Shannon Tier, Tasmania, containing an unknown mineral referred by him to Ca2SiO4. Subsequently Bowen (Amer. J. Sci., 1922, p. 30) pointed out the close correspondence between the optical properties of Paul's mineral and of the artificial βCa2SiO4 prepared by Day, Shepherd and Wright. Still later (Geol. Mag., 1927, p. 43) the writer of this note ventured to apply the name shannonite to the mineral of this singular occurrence. Since that time through the kindness of Mr. P. B. Nye, Government Geologist of Tasmania, a specimen of the rock described by Paul from Shannon Tier has been obtained and examined. That the specimen examined is identical with the rock described by Paul is clearly indicated by his detailed description and the photomicrograph which accompanies his paper. Unfortunately my own determinations are not in agreement with those of Paul, and the purpose of the present note isto state the nature of these discrepancies. The rock is a felspar-free nepheline-basalt of which the chief constituents are idiomorphic nepheline, a titaniferous augite, olivine (chrysolite), the unknown mineral of Paul, biotite, apatite, magnetite, perofskite, and minor amounts of interstitial analcime. The described eudialite has not been discovered, and from the description attached to the photomicrograph this mineral appears to have been confused with nepheline. I find further that the properties of the unknown mineral agree, not with those of any of the artificial calcium orthosilicates, but with those of monticellite. The two olivines are readily distinguished in thin section, the chrysolite occurring as chadacrysts and the monticellite as oikocrysts, the latter appearing as shapeless grains often surrounding chrysolite and enclosing numerous idiomorphic crystals of nepheline and magnetite, and thus belonging to a late stage in the crystallization history of the rock. The chrysolite moreover is readily distinguished—apart from these textural differences—by its higher birefringence and larger optic axial angle (near 90°).
The Cretaceous Shales of Jamaica
Authors: Trechmann C. T.
Published: May 2009

A well preserved specimen 46mm. long and 22·5mm. wide (Fig.17) was found by Mr. R. Cory near Catadupa. The body whorl is contracted below the suture and has ten varices which die away at the anterior contraction and are slightly acute at the shoulder; the anterior part of the shell has five wavy spiral ridges. A smaller and more delicate but poorly preserved form (Fig. 18), with similar but more anteriorly produced varices, occurs just above the Barrettia limestone at St. Ann's Great River and resembles specimens of L. crassicostata Stol. from Assam figured by Spengler (Pal. Ind., N. Series, vol. viii, mem. i, 1923, pl. iii, figs. 34a, and b). Another species of Lyria or Volutilites (Fig. 16) with elongated spire has about 7 coarse uneven varices on the body whorl and occurs as badly preserved casts in the Providence shales. It attains a length of 47 mm.
Silurian Graptolites from Studley Park, Melbourne, Australia
Authors: Jones O. A.
Published: May 2009

Four species of Monograptus are described and the age of the strata shown to be that of the zone of M. nilssoni of the Lower Ludlow of Great Britain.
The Unconformity between the Coal Measures and the Lower Carboniferous Rocks in the Clapton-Clevedon District, Somerset
Authors: Dixey F.
Published: May 2009

In 1915 I published a short paper in which it was shown that the Coal Measures of the Clapton area on the northern side of the Clifton-Clevedon ridge, Somerset, rested with strong unconformity upon the Carboniferous Limestone and all older rocks. Subsequently Professor S. H. Reynolds, having observed the relations at Court Hill, Clevedon, where the Carboniferous Limestone is clearly thrust over the Coal Measures, saw no reason to differ from the earlier observers, Buckland and Conybeare, the officers of the Geological Survey, and Lloyd Morgan, all of whom regarded the Main Limestone-Coal Measures junction south of Clapton as a faulted one; accordingly, on the map accompanying his paper, Professor Reynolds showed the boundary as a fault as far as the eastern limit of the Coal Measures, even where they transgress from the Main Limestone across the Lower Limestone Shales. At a later date Dr. E. Greenly, in a description of the sections at East Clevedon Gap, about three miles west of Clapton, referred to the unconformity as follows: “Whether, as believed by A. Vaughan and F. Dixey, there be unconformity, the whole of the Visean, with apparently the Lower Coal Measures as well, having been locally removed by inter-Carboniferous erosion, is a question that will not be discussed in this paper. But, independently of that question, there is reason to suspect that the base is cut out, for the lowest visible sandstones on the wooded bluffs are buckling over, as if driven forward on a thrust-plane. Should serious unconformity be eventually proved, this thrust need not be of much tectonic importance. In any case, the plane, whatever its nature, is over-stepped by the Bella-Vista Thrust-plane…”
Modern Pools and Carboniferous Analogies
Authors: Griffiths Benjamin Millard
Published: May 2009

The origin of coal is a difficult problem which is very far from being solved. The Coal Measure flora has long been extinct, and the modern representatives are feeble folk, almost crowded out of existence by plants of very different appearance and internal structure. The modern marsh flora is not primitive but secondary, and consists almost entirely of land plants which have taken to the water habitat again, just as the whale, porpoise, and seal are land animals which have gone back to rejoin their remote ancestral relatives in the sea. Homologous comparisons between past and present are therefore practically impossible, but some common pool developments of to-day may provide useful analogies if nothing more.
Studies in Avonian Brachiopoda: II. The Genus Camarophoria
Authors: George T. Neville
Published: May 2009

The genus Camarophoria was established by King in 1846 for certain Permian brachiopods bearing internal structures similar to those of the Pentamerids. The essential features were the presence in the ventral valve of a spondylium (“an arch-shaped process”) supported by a median septum (“medio-longitudinal plate”). “The arch-shaped process and its supporting or suspending plate correspond in every respect except in degree with the apophysary system belonging to the large valve of Pentamerus.” In the dorsal valve there is developed a high median septum supporting a well-developed spondylium (“spatula-shaped process”).
The Carlisle Basin
Authors: Dixon E. E. L. , Trotter F. M.
Published: May 2009

Professor Gregory's kindly review of the Carlisle memoir raises once more the vexed question of the structure of the New Red rocks of that district. Two borings, one at Abbey Town and the other at Bowness, prove a thick series of variegated shales in the drift-covered western part of the area. A third boring proved red beds beneath the Lias at Great Orton. As Professor Gregory points out, the correlation of these red beds with the Abbey Town shales is uncertain. Though expressing the same caution, he had nevertheless previously adopted the correlation, his section through Great Orton, here reproduced, showing the beds at the two places as continuous. In what follows it will be easy to distinguish the evidence relating to Great Orton from that dealing specifically with the Abbey Town shales.
The Recent Geology of the Northern Fayum Desert
Authors: Gardner Elinor W.
Published: May 2009

A preliminary account of the subject of this paper was given before Section H of the British Association at the Oxford meeting in 1926 (1, 2).
On the Relations between Silica, Alumina, and the Bases in Eruptive Rocks, considered as a Means of Classification
Authors: Shand S. J.
Published: May 2009

The Geological Magazine did me the honour in 1914 to publish a paper in which I proposed a classification of eruptive rocks on the basis of the “degree of saturation” of the constituent minerals with silica. Any mineral which is proved by its field associations to be stable in the presence of free silica, under such conditions as prevail in natural rock magmas, was said to be “saturated” with regard to silica. Other minerals, such as leucite and olivine, which are not stable in presence of free silica, within the ordinary range of magmatic temperatures, were said to be “unsaturated” with regard to silica. Eruptive rocks were then classified as “oversaturated”, if they contained quartz or tridymite; “under-saturated”, if they contained any unsaturated minerals; and “saturated” if neither free silica nor any unsaturated mineral was present.
On Senonian Ammonoidea from Jamaica
Authors: Spath L. F.
Published: May 2009

In his paper on “The Yellow Limestone of Jamaica and its Mollusca” (Geological Magazine, Vol. LX, 1923, p. 345) Dr. C. T. Trechmann referred to an Upper Senonian fauna from shales at Providence, near Port Antonio, underlying a limestone with Rudistae. He recorded Baculites from the upper portion of these shales, and “rather low in the sequence” he collected some ammonites, one of which had been identified by the writer as belonging to the genus Parapachydiscus. The Shales at Providence had already been mentioned by the late Mr. Lucas Barrett1 as containing Baculites and Hamites, and in his collection, now in the British Museum (Natural History), there are preserved a number of fossils including the Pholadomya and Trigonia he recorded and two fragments of Hamites. The matrix of these is the same as that of Dr. Trechmann's examples, namely a brown calcareous sandstone, and the ‘Hamites’ in both collections belong to the same species, but Mr. Lucas Barrett's Baculites I have not been able to trace.
Some New Silurian Trilobites
Authors: Reed F. R. Cowper
Published: May 2009

Pygidium elongated, sublanceolate, bluntly pointed posteriorly. Lateral lobes flattened, horizontal, composed of three pairs of pleurae and a median postaxial piece. Axis short, conical, convex, tapering rather rapidly to blunt tip, less than one-third the length of the pygidium and about one-third its width, subcarinate posteriorly, faintly marked off from postaxial piece by weak circumscribing furrow; furnished at anterior end with one strong narrow complete ring, marked off by strong furrow, followed by weaker second ring defined by faint complete furrow, and with traces of a third incomplete ring; posterior two-thirds of axis devoid of annulations. Postaxial piece long, narrow, widening somewhat posteriorly, descending gradually to level of lateral lobes from tip of axis and becoming flattened but distinctly carinated for its whole length. First lateral pleura strongly falcate, bending back suddenly at fulcrum where it is widest and thence narrowing rather slowly to acutely pointed free tip projecting backwards beyond margin; pleural furrow submedian, diagonal, parallel to posterior edge of pleura, running nearly to tip. Second lateral pleura elongate, sublanceolate with tip bent back slightly and projecting freely beyond margin as short recurved point; pleural furrow median, slightly diagonal, not reaching tip. Third lateral pleura sublanceolate, broader than second pleura, incompletely marked off from postaxial piece posteriorly, the bounding furrow not quite reaching the margin but curving gently outwards at its end; tip of pleura undefined and not projecting beyond margin; pleural furrow median, slightly wavy, running nearly straight back parallel to its fellow, curving inwards a little at its end but not clearly connected with bounding furrow. All pleural and interpleural furrows of equal strength. Posterior lateral margins of pygidium behind tips of second pleurae forming nearly half its length and describing a long simple slight curve on each side, uniting behind in a blunt point at about 60°, the median carina of the postaxial piece extending to its tip.
Notes upon the small species of Chonetes found in the Lower Carboniferous around Bristol
Authors: Smith Stanley
Published: May 2009

Small species of Chonetes are frequently found crowding the limestones in the lower part of the Avonian Succession round Bristol and in the Mendips. Of these Ch. cf. hardrensis (Phill.) is the most persistently abundant throughout its range Km-Zl, but the two other species, Ch.failmulensis sp. nov. and Ch. stoddarti, Vaughan, here mentioned, occur in equally large numbers at particular levels within that horizon. The following notes are the outcome of the study of the material recently collected by Professor S. H. Reynolds, and myself, at St. Monica's Home of Rest, Westbury-on-Trym, but this has been considerably supplemented by specimens obtained from other localities in the district.