bluuebunny/crossref_metadata_2025_split huggingface dataset:
The major fault zone of central Vestspitsbergen
Authors: Mcwhae John Ross Hope 
Published: October 2009

Summary
A deformation belt runs southwards from Wijdefjorden through the length of central Vestspitsbergen, a distance of over 190 miles.
From the stratigraphical summary several factors emerge that are relevant to the structural history.
1. The pre-Downtonian rocks are crystalline schists with a general N.-S. trend resulting from an earlier orogeny.
2. There was a basin of sedimentation in the Billefjorden area in Lower and Middle Carboniferous times.
3. The Carboniferous to Lower Permian succession is concordant in the central portion of this basin.
4. A strip of coarse conglomerates overlying an old fault-line suggests weak faulting activity in Middle Carboniferous times.

Fault activity occurred in Upper Devonian times, probably with a strong compressive phase in the earlier part which was followed by weaker gravity faulting
1
near the end of the period. Again in Tertiary times, either gravity faults or flexures formed, depending on the competence of the rocks affected.

Parallelism with the trend of the pre-Downtonian metamorphic rocks is striking and renewed dislocations along the Upper Devonian fractures seem to be common.
It is concluded that the major Upper Devonian fractures are not gravity faults. Two theories of genesis are possible : firstly, transcurrent faulting with associated upthrust wedges; secondly, high-angle thrusting with a later phase of gravity faulting. The data available appear to favour the second.
A pinnacle of chalk penetrating the Eocene on the floor of a buried river-channel at Ashford Hill, Near Newbury, Berkshire
Authors: Hawkins Herbert Leader 
Published: October 2009

Summary
An isolated pinnacle of chalk,about 175 feet across and at least 150 feet above its normal level,rises through the Reading Beds and part of the London Clay near Ashford hill, and is associated with a drift-filled channel whose floor is, at its deepest proved point, 90 feet below the present ground-level. The channel reaches its greatest depth on the top of the chalk pinnacle, and seems not to extend beyond it. It is filled mostly with peaty silts with subordinate beds of gravel; and at depths of about 40 feet from the surface the pollen-content of the peats indicates a Lateglacial age. At the deepest point, almost 50 feet of alternating varves and Coombe Rock underlie the Late-glacial drift, in what appears to have been a swallow-hole.
The pinnacle of chalk into which this pit was excavated has evidently been driven up through the Eocene when in a plastic state; its elevation and exposure must have antedated the development of the deep channel which apparently ends at it. In an attempted explanation of these associated anomalies (both of which seem to have developed during the Glacial Period) it is suggested that the chalk at the point of convergence of two faults may have been subjected to deep freezing and subsequently to "eruption" as a tectonically localized "valley bulge".
The Interglacial at Clacton-On-Sea, Essex
Authors: Pike Kathleen , Godwin Harry 
Published: October 2009

Summary

Pollen analyses through 18 feet of deposits in the Clacton channel show that the upper part of the freshwater beds falls within a warm-temperate forest period, whilst the overlying estuarine deposits formed in a period of declining warmth in which coniferous forests became dominant. The preponderance of pollen of
Abies
(silver fir) in these deposits is noteworthy.

The marine transgression thus took place in the middle to second half of an interglacial cycle, and it is suggested that this may have been due to an isostatic depression of the North Sea basin comparable with similar movements of other interglacial periods.
The pollen diagram shows little correspondence with British diagrams from the (older) Cromer Forest Bed, or from beds taken to belong to the Last Interglacial. Similarly, comparison with the range of West European interglacial pollen diagrams suggests the possibility that the Clacton deposits may relate to the Penultimate Interglacial.
The Interglacial Deposits at Histon Road, Cambridge
Authors: Walker Donald , Godwin H. , Sparks Bruce W. 
Published: October 2009

Summary

A pollen diagram from the muds exposed in a sewer trench near Cambridge is presented, together with a record of the macroscopic plant remains obtained from the same deposits. The two zones of the diagram are correlated with zones
g
and
i
of the Last Interglacial period in Europe.
The migmatitic Older Granodiorite of Thorr district, Co. Donegal
Authors: Pitcher Wallace Spencer 
Published: October 2009

Summary
The Donegal granite is emplaced in highly folded Dalradian strata. The meta-sediments comprise pelitic and semi-pelitic schists, siliceous granulites, calcareous rocks and quartzites; these rocks are intruded by numerous basic sills of pre-metamorphic age.
In the district of Thorr, on the northern margin of the granite, these strata are highly metamorphosed and sillimanite is the characteristic mineral of the pelitic types. This metamorphism is superimposed on one of low grade and is connected with the presence of heterogeneous rocks of tonalitic character; these are collectively called the " Older Granodiorite " and they contain many large enclaves of meta-sediment. Between such separated masses there is a concordance of structure, and the stratigraphical relationships are preserved. The presence of such a " ghost stratigraphy ", which indicates a considerable measure of replacement, has to be equated with the evidence of composition, which requires incorporation of country rock, and, again, with the evidence of sharp contacts and flow which suggests intrusion. A hypothesis requiring the partial mobilization of country rock granitized in place is contrasted with that of piecemeal stoping and marginal assimilation.
The Older Granodiorite is intruded by a series of microgranite sheets and dykes with associated aplites and pegmatites. These form the early phases of the relatively xenolith-free, sodi-potassic Newer Granites, which are of magmatic origin and constitute the greater part of the Donegal mass.
A wide belt of shearing enters the south-eastern part of the Thorr district and all the rocks suffer varying degrees of cataclasis. This may be a protoclastic deformation connected with the forceful intrusion of the Newer Granites. Late events in the geological history include the formation of a perfect joint system. The prominent north-north-westerly joints occasionally become faults, and they commonly afford the paths for numerous Tertiary dykes.
Hornblende-lamprophyre dykes of basaltic parentage from the Skaergaard area, East Greenland
Authors: Vincent Ewart Albert 
Published: October 2009

Summary
In a complete sample of the Tertiary dykes in a small area of the Skaergaard peninsula, the majority of the forty specimens are ophitic olivine-bearing or olivine-free dolerites of a type prevalent in the East Greenland coastal dyke swarm as a whole. Some, however, are more alkaline dolerites, showing evidence of having crystallized from a magma fraction richer in volatile components and alkalis, and are later in the intrusion sequence. These oligoclase-dolerites are further seen to grade into camptonitic hornblende-lamprophyres.
A genetic lineage is traced from normal dolerites, through oligoclase-dolerites, to comptonites on the basis of textures, structures and mineralogical variations in the rocks, which have almost certainly all originated from the same parental basic magma.
Chemical analyses show the oligoclase-dolerites and camptonites to be poor in silica but somewhat enriched in alkalis, particularly in potash; and that there is little difference in chemical composition between oligoclase-dolerites and camptonites, the latter type being the result of crystallization at lower temperatures from a more watery magma.
An explanation of the genesis of the various types in terms of fractional crystallization and filter-press action in compatible with the field, petrographic and chemical evidence.
Linear structures and their relation to movement in the Caledonides of Scandinavia and Scotland
Authors: Kvale Anders 
Published: October 2009

Summary

The author considers that, although Dr. D. B. McIntyre's geometrical reconstruction of the structures observed in mid-Strathspey (1951,
Q.J.G.S.
107
, 1–22) may be essentially correct, his kinematic interpretation of the structures is open to question. Dr. Mclntyre's evidence is discussed briefly. Sander's evidence for his theory of the relation of plane of symmetry to direction of movement is also reviewed. Structures in the Caledonides of Norway cannot be brought into agreement with Sander's theory, and it is concluded that the theory needs modification. A plane of symmetry may be formed at right angles to a lineation which is parallel to the direction of movement. Linear structures reflect local conditions of deformation and may under certain conditions be formed at any angle with the principal direction of movement. Brief remarks are given on the formation of a lineation and on the general picture of linear structures in the Caledonides. Comments are made on the occurrence of minor linear structures in the Scottish Highlands, and their importance. Variation in trend of linear structures in the Highlands is briefly discussed. It is suggested that when the linear structures of the Highlands are more completely known it may be possible to explain all structures as having been formed during the Caledonian orogeny. The Moinian and the Dalradian may both be Caledonian geosynclinal sediments, corresponding to the Norwegian Sparagmite Formation and Soros Group respectively.
The petrography and geological significance of the post-Cambrian minor intrusions of Assynt and the adjoining districts of North-West Scotland
1
Authors: Sabine Peter Aubrey 
Published: October 2009

Summary
The post-Cambrian sills and dykes described occur mainly in the Assynt district of the North-West Highlands of Scotland. The principal types are grorudites, Canisp porphyry (biotite, albite-oligoclase, aegirine-augite porphyrite), hornblende-porphyrites, nordmarkitic rocks, vogesites and ledmorites and related rocks. They are emplaced in Lewisian Gneiss, Torridon Sandstone and Cambrian sediments, and some also occur in the Moine schists. The intrusions are affected by the Caledonian thrust movements. The tectonic distribution of the grorudites leads to the recognition of the Glencoul and Ben More thrust-masses as parts of a single tectonic unit. South of Conival the Benmore thrust-plane is of greater importance than to the north, and is renamed the Assynt thrust-plane. The sills in the Moine Series are metamorphosed and are thought to have been emplaced after the inception, but before the close, of the Caledonian thrust movements; some part at least of the Mo^ne metamorphism is thus of post-Cambrian age. Assimilation of limestone has probably no relation to the production of lime-magnesia pyroxene in the vogesites, nor to the production of highly alkaline rock types. A mechanism of differentiation of the post-Cambrian suite is suggested. Both major and minor intrusions have been emplaced by injection; in places the thickness of the sills amounted to several hundred feet, and had considerable effect in up-doming the strata over which the Moine schists were thrust.
The beds above the Carboniferous Limestone in North-West County Clare, Eire
Authors: Hodson Frank 
Published: October 2009

Summary

The lithological and faunal succession in the beds above the Carboniferous Limestone over an area of about 50 square miles in North-West County Clare is described. This area has the town of Lisdoonvarna at about the central point and includes the Cliffs of Moher on the Atlantic coastline. Some 1300 feet of beds are preserved above the limestone and are to be referred to the upper part of the
Homoceras
and Lower
Reticuloceras
stages of the Namurian. Seventy-three fossiliferous bands, belonging to 10 faunal horizons, have been found and vertical sections measured to show their relationships. The succession, in this part of County Clare, is shown to be very condensed in its lower portion. There exists a considerable non-sequence above the Carboniferous Limestone. The Geological Survey map is shown to embody certain errors and a geological sketch-map is given which attempts to rectify these.
The composite granitic gneiss of western Ardgour, Argyll
Authors: Harry William Trevelyan 
Published: October 2009

Summary

The Moine Upper Psammitic Group of western Adrgour, Argyll, is steeply folded into an anticline running across country for a number of miles. Along the axis of the anticline is exposed a belt of composite gneisses with a foundation of pelitic Moine schist. The gneisses adjacent to the Moine Upper Psammitic Group are usually oligoclase-biotite-quartz-gneiss still presenting many of the features of pelitic schist. At deeper structural levels the composite gneisses are of granitic composition, containing quartz, microcline, oligoclase and biotite. Replacement textures are pronounced. This composite granitic gneiss develops a subordinate amount of augen-gneiss due to the growth of microcline porphyroblasts. Both the granitic and oligoclase-biotite-quartz-gneiss show migmatitic structures. The latter rock includes types megascopically identical with the
lit-par-lit
regional injection gneisses extensively developed in adjacent districts of the West Highlands of Scotland.

The granitic gneiss was formed by syntectonic advance along pelitic schist of a silica-potash “front” of metasomatism preceded by a Na, Ca, Mg “front” of felspathization, forming oligoclase-biotite-quartz-gneiss. “
Lit-par-lit
injection” types of the latter are ascribed to metamorphic segregation of quartz-felspar folia. Both gneisses are replacements essentially in situ. An attempt is made to explain the textural varieties within the granitic gneiss (augen-gneiss, aplite etc.) by the variable interplay of crystallization and earth-movement during granitization, combined in some cases with metamorphic differentiation.
Graptolites from Anticosti Island
Authors: Barrass Robert 
Published: October 2009

Summary

In graptolite collection sent to Professor Lapworth near the end of the 19th century are some pieces of limestone from Anticosti Island, Canada. These form the basis of the present study, in which the structure and development of two new species of
Amplexograptus
and a species of
Climacograptus
are described from specimens preserved compressed and in relief. Much of the investigation was carried out using serial sections made with the Croft parallel grinder.

The amplexograptids resemble
Amplexograptus
[
Climacograptus
]
inuiti
(Cox) but were not put into the genus
Climacograptus
because they possess characters relating them to
Diplograptus s.l.
, e.g, a high length ratio of the excavation, long interthecal septa sloping to the axis of the rhabdosome, and a sub-rectangular cross-section. The climacograptid features, e.g. a low length ratio of the excavation, interthecal septa parallel to the axis and a circular or nearly circular cross-section, are shown in
Climacograptus
aff.
scalaris
. Compressed specimens of
Amplexograptus elongatus
(which has very small mesial thecal flanges) show both amplexograptid and orthograptid views and an attempt is made to account for this.

I. Introduction
The material investigated consists of a few small pieces of limestone from Anticosti Island, Canada, included in a collection of graptolites sent to Professor Lapworth at Birmingham towards the end of the 19th century (Bulman 1950). The specimens figured here will be deposited, temporarily at least, with the Department of Geology, Birmingham University. The limestone is from the following three main localities (Twenhofel 1928, fig. 1.): Observation Cliff, North Shore; Macdonald's Cove
The Geological History of the English Channel
Authors: King William Bernard Robinson 
Published: October 2009

Summary
The geology of the English Channel has long been known to be much more complex than might appear from a study of the land areas on either side. The most important work on the subject was that of Dangeard, who examined a number of dredge samples and published his results in 1929. In recent years investigations with a free-drop cover which collected samples of rock in place, and geophysical work, largely that of Dr. M. N. Hill, have added much new information.
The data now available are brought together and analysed. Maps showing the areas where each major rock group occurs at surface or at depth and estimates of thicknesses have been prepared. From these a map of the outcrops under the Channel and a contour map of the sub-New Red Sandstone—Mesozoic surface (the so-called Palaeozoic floor) have been drawn.
The history of the area is then reviewed and it is concluded that since the Armorican orogeny the Channel has been an area with a tendency to intermittent downwarps while the surrounding land areas cf Devon and Cornwall on the one hand and Brittany on the other have been areas with intermittent uplift. This leads to the conclusion that many of the present uplands of Palaeozoic rock were blocked out in early times and that the present edges of these areas are not far from the positions they have occupied since New Red Sandstone times. It is suggested that palaeogeographical maps of the Mesozoic in this region should show a
The Dalradian Geology of the Creeslough Area, Co. Donegal
Authors: McCall Gerald Joseph Home 
Published: October 2009

Summary
In the Creeslough area, folded and metamorphosed Dalradian sediments with sills of metadolerites are intruded by a member of the Donegal granite series. The preservation of original sedimentary features makes it possible to establish a succession of about 6000 feet of sedimentary rocks. The lower beds accumulated slowly in a restricted trough; the appearance of thick gritty quartzites marks an increase in the supply of detritus; the overlying sediments show evidence of emergence and the highest beds indicate a return to slow sedimentation. The intrusion of the dolerite sills produced a thermal alteration of the sediments which has resisted the later orogenic metamorphism.
The major folds run NE.-SW., are overturned towards the north-west and are associated with slides. A phase of orogenic metamorphism, of no high grade, was followed by the uprise of the local phase of the Donegal granite and the development of sillimanite, staurolite, kyanite and garnet along the granite margin. The granodiorite and its aureole rocks were then strongly sheared, probably as a result of pressure from the deeper part of the pluton. A suite of lamprophyre dykes was intruded before the end of the shearing.
I. Introduction
A knowledge of the Creeslough area is important for the study of Donegal geology in that there is here provided a lengthy succession of Dalradian rocks which retain unchanged many of their original sedimentary characters. This circumstance enables their tectonics to be interpreted with confidence. Moreover, the sedimentary rocks and the associated metadolerite intrusions present many problems in metamorphism—the
On the Time Relations between Regional Metamorphism and Permeation in Delting, Shetland
Authors: Flinn Derek 
Published: October 2009

Summary
The metamorphic rocks of Delting are a thinly bedded succession of pelites, semipelites, impure quartzites, and calcareous rocks, about 36,000 feet in thickness, with a strike approximately north-north-eastward and bedding mostly vertical. Scattered throughout the succession are metamorphosed basic igneous rocks. The earliest recognizable episode after the deposition of the sedimentary rocks was the regional metamorphism. A number of zones of regional metamorphism, equivalent to the Barrovian zones of the South-West Highlands, have been delimited. They show that the intensity of regional metamorphism increased towards the south-west. The next episode was the establishment of two belts of permeation, within which the rocks generally were intensely recrystallized, but not in the same manner in the two belts. The permeation was accompanied by thermal metamorphism of the rocks in the immediate neighbourhood of the belts.
The variation in the intensity of this thermal metamorphism, both within and between the two belts, suggests that the permeation took place after the regional metamorphism. From this, and from the absence of any relation between the distribution of the permeation belts and that of the zones of regional metamorphism, the conclusion is reached that in Delting the regional metamorphism was neither the cause nor the result of the permeation, but that both are the consequence of forces acting on a larger scale and at depth.
I. Introduction
(a) Locality
The area of Delting, which is described in this paper, is a part of the Mainland of Shetland. Four long narrow arms of the sea, Olna Firth
A Review of the Jurassic of Western Sicily Based on New Ammonite Faunas
Authors: Warman Harry Robert , Arkell William Joscelyn 
Published: October 2009

Summary
The first part of the paper gives descriptions and profiles of four key Jurassic sections in western Sicily from which ammonites have been collected at various levels, and discusses the stratigraphy and the relations of the Jurassic to earlier and later systems. It is shown that thick limestones previously classed as Tithonian belong largely to the Cretaceous and in places are even Eocene. The tectonic implications are discussed. The second part of the paper lists 11 assemblages of ammonites collected in the four sections and ranging in age from Lower Bathonian to Tithonian. Notes on their correlation and òn a number of other assemblages collected in Sicily are also given. Lower and Upper Bathonian and Lower and Upper Oxfordian assemblages new to Sicily are recorded. The Jurassic palaeogeography of Sicily and neighbouring regions is inferred from the vertical and horizontal distribution of the ammonite faunas and their affinities with those in other regions.

Part I.
Structure and Stratigraphy [H. R. W.]

I. Introduction
The field work on which this paper is based was carried out in routine geological investigations on behalf of the D'Arcy Exploration Company during exploration for oil. Acknowledgment is made to the Chairman and Directors of the Anglo-Iranian Oil Company Ltd., of which the D'Arcy Exploration Company is a subsidiary, for permission to publish the following results deriving from these investigations.
In an attempt to amplify our knowledge of the regional stratigraphy, certain major exposures of pre-Tertiary rocks in western Sicily have been examined and the thicknesses