bluuebunny/crossref_metadata_2025 huggingface dataset:
c-Kit Function Is Necessary for In Vitro Myogenic Differentiation of Bone Marrow Hematopoietic Cells
Authors: Xaymardan Munira , Cimini Massimo , Fazel Shafie , Weisel Richard D. , Lu Wei-Yang , Martin Ulrich , Harvey Richard P. , Li Ren-Ke
Published: May 2009

In recent years, the differentiation of bone marrow cells (BMCs) into myocytes has been extensively investigated, but the findings remain inconclusive. The purpose of this study was to determine the conditions necessary to induce myogenic differentiation in short-term cultures of adult BMCs, and to identify the BMC subpopulation responsible for this phenomenon. We report that high-density cultures of murine hematopoietic BMCs gave rise to spontaneous beating cell clusters in the presence of vascular endothelial and fibroblast growth factors. These clusters originated from c-kitpos cells. The formation of the clusters could be completely blocked by adding a c-kit/tyrosine kinase inhibitor, Gleevec (imatinib mesylate; Novartis International, Basel, Switzerland, http://www.novartis.com), to the culture. Cluster formation was also blunted in BMCs from c-kit-deficient (KitW/KitW-v) mice. Clustered cells expressed cardiomyocyte-specific transcription factor genes Gata-4 and Nkx2.5, sarcomeric proteins β-MHC and MLC-2v, and ANF and connexin-43. Immunostaining revealed α-sarcomeric actinin expression in more than 90% of clustered cells. Under electron microscopy, the clustered cells exhibited a sarcomeric myofiber arrangement and z-bands. This study defines the microenvironment required to achieve a reproducible in vitro model of beating, myogenic cell clusters. This model could be used to examine the mechanisms responsible for the postnatal myogenic differentiation of BMCs. Our results identify c-kitpos bone marrow hematopoietic cells as the source of the myogenic clusters.

Disclosure of potential conflicts of interest is found at the end of this article.
mAb 84, a Cytotoxic Antibody that Kills Undifferentiated Human Embryonic Stem Cells via Oncosis
Authors: Tan Heng Liang , Fong Wey Jia , Lee Eng Hin , Yap Miranda , Choo Andre
Published: May 2009

The monoclonal antibody mAb 84, which binds to podocalyxin-like protein-1 (PODXL) on human embryonic stem cells (hESCs), was previously reported to bind and kill undifferentiated cells in in vitro and in vivo assays. In this study, we investigate the mechanism responsible for mAb 84-induced hESCs cytotoxicity. Apoptosis was likely not the cause of mAb 84-mediated cell death because no elevation of caspase activities or increased DNA fragmentation was observed in hESCs following incubation with mAb 84. Instead, it was preceded by cell aggregation and damage to cell membranes, resulting in the uptake of propidium iodide, and the leakage of intracellular sodium ions. Furthermore, examination of the cell surface by scanning electron microscopy revealed the presence of pores on the cell surface of mAb 84-treated cells, which was absent from the isotype control. This mechanism of cell death resembles that described for oncosis, a form of cell death resulting from membrane damage. Additional data suggest that the binding of mAb 84 to hESCs initiates a sequence of events prior to membrane damage, consistent with oncosis. Degradation of actin-associated proteins, namely, α-actinin, paxillin, and talin, was observed. The perturbation of these actin-associated proteins consequently permits the aggregation of PODXL, thus leading to the formation of pores. To our knowledge, this is the first report of oncotic cell death with hESCs as a model.

Disclosure of potential conflicts of interest is found at the end of this article.
Rolled Garnets from Morar, Inverness-shire
Authors: Peacey J. S.
Published: May 2009

A thin section of garnetiferous pelitic schist is described in which the rotation of the garnets is in either of two directions. Microfolds are seen in the slide and the garnets were rotated in opposite directions on opposite limbs of the folds. Their relation to minor structures is suggested.
A possible large-scale sinistral displacement along the Great Glen Fault in Scotland
Authors: Storetvedt K. M.
Published: May 2009

Comparison of Old Red Sandstone palaeomagnetism for NW Scotland and Norway lead to the hypothesis of a 200–300 km sinistral movement along the Great Glen Fault. The displacement is thought to be of late Caledonian (late Devonian) age. The new palaeogeographic reconstruction of Northern Britain (prior to late Caledonian times) seems to have interesting geological implications.
The Abakaliki pyroclastics – Eastern Nigeria: new age and tectonic implications
Authors: Uzuakpunwa A. B.
Published: May 2009

Basic to intermediate pyroclastic rocks of pre-Albian age are overlain by the Abakaliki shale of Asu River Group in Eastern Nigeria. The shale has been assigned Albian age on the basis of abundant (middle Albian?) ammonites found in it. It was folded (together with the pyroclastics) about a NE–SW trending anticlinal axis during the Santonian time. This new evidence of an early Cretaceous volcanism supports a pre-Albian rifting of the African shield prior to the opening of the Southern Atlantic. The latter event took place (probably in stages) during Albian time (i.e. less than 110 Ma ago), with a widespread marine transgression in West Africa and South America.
Dalradian margarite: a preliminary note
Authors: Chinner G. A.
Published: May 2009

Margarite occurs in quartz-bearing Dalradian graphitic schists both as a primary phase and as an alteration product of kyanite. The disposition of alteration products in these rocks demonstrates clearly the role of an externally imposed gas phase in determining margarite development.
Angra Pequena (Lüderitzbucht) and Subaerial Denudation
Authors: Rand R. F.
Published: May 2009

In recent years the name of Angra Pequena, conferred by Bartholomew Diaz, has been somewhat obscured by the designation Lüderitzbucht, the name given to this port during the German occupation. The latter name still holds, although a compromise, whereby the geographical area should retain the old name and the town be known as Lüderitz, seems desirable.
Some Points in Sedimentary Petrography
Authors: Rastall R. H.
Published: May 2009

For several years prior to 1914 the writer was engaged in the study of the mineral composition of loose detrital sediments with special reference to the rarer minerals and so-called heavy constituents of sands, the principal object of these investigations being an endeavour to ascertain what conclusions, if any, could be drawn as to the source and past history of the material and their bearing on stratigraphical and palæogeographical problems along the lines laid down by Dr. Thomas in his well-known researches on the New Red Sandstone of south-western England. In those days the subject was still in its infancy, and there were no standard books of reference dealing with it, such as are now abundant: it was necessary to evolve methods and to learn the characteristics of the minerals in grains by experimental investigation and by reference to the comparatively few published descriptions then available. This work was carried out chiefly on the Lower Greensand between the borders of Buckinghamshire and the Wash, but a good deal was also done on the superficial deposits of the neighbourhood of Cambridge and elsewhere, and some of the results obtained on the last-named group were published. The study of the Lower Greensand was, however, still incomplete at the end of 1914. After the war, for reasons unnecessary to detail here, it was not possible to continue the investigation of this particular formation on a more extended scale, as had been originally intended, and the results attained up to 1914 were published in the Geological Magazine.
The Pluvial Period of Central and Southern Italy
Authors: Harmer F. W.
Published: May 2009

The typoscript of this paper was found by me among my father's MSS., after his death on 11th April, 1923. There was evidence to show that it was written rather earlier than 1908, and it is obviously the first part of a paper which had been put on one side during the preparation of “The Pliocene Mollusca of Great Britain”. The typoscript ended with the heading “Floods of Miocene and Pliocene Periods”, but I have no reason to believe that this section was ever prepared. The three figures here reproduced were with the typoscript, but others which it had been intended to use in illustration of the paper have not been found.
Rhythmic Banding of Ferric Oxide in Silicified Rhyolite Tuffs.
Authors: Chhibber H. L.
Published: May 2009

A case is described of rhythmic banding by iron oxide in a rhyolitic tuff. The fine-grained tuff has acted as a medium for the production of Liesegang rings, the irregularity in the rings being ascribed to minute variations in the texture of the rock, naturally less homogeneous than a gel.
U-Shaped Burrows in the Lower Lias of Somerset and Dorset
Authors: Coysh A. W.
Published: May 2009

The weathered surfaces of the limestones and calcareous shales of the Lower Lias in Somerset and Dorset sometimes exhibit curious paired markings. On careful examination these prove to be cross sections of U-shaped burrows of organic origin, appearing as two circular markings connected by a shallow depression or by a slight variation in the character of the matrix. Similar burrows have been described from the Lower Estuarine sandstone of Blea Wyke, on the Yorkshire coast. Dr. F. A. Bather has discussed their origin and structure in detail and has assigned them to the genus Arenicolites, which was established by J. W. Salter for “all worm burrows with double openings”. Other species of the genus have been described from arenaceous and argillaceous beds of Longmyndian, Ordovician, and Upper Carboniferous age, but as far as the author is aware, the species here recorded is the first that has been mentioned from the calcareous rocks of the Lower Lias of England.
II.—On the Age and Geological Position of the Blue Clay of the Western Counties
Authors: Eyton Charlotte
Published: May 2009

It is a well-known fact that the shell-bearing gravels of the Western counties repose in many localities immediately upon a bed of blue or grey clay. This bed has been described as it appears in Lancashire and Cheshire, by Mr. Binney; and more recently by Professor Hull; in North Wales by Mr. E. D. Darbishire; near Rugby by Mr. Wilson; and in numerous localities by Messrs. Taylor, H. F. Hall, D. Mackintosh, and other contributors to the GEOLOGICAL MAGAZINE, in various papers, all testifying to the great extent and importance of this bed.
IV.—Contributions to British Fossil Crustacea
Authors: Woodward Henry
Published: May 2009

In my fourth Eeport to the British Association, I described, among other Crustacea, two species belonging to the genus Cyclus, one of which still remains unique. Since that date, I have, by the kindness of Professor T. Rupert Jones, F.G.S., received a number of specimens of this genus, collected by Prof. Harkness, F.R.S.; Mr, Joseph Wright, of Belfast; and Mr. J. H. Burrow, of Settle, Yorkshire; from the Carboniferous Limestone, which I now propose to describe.
II.—The Principal Characters of American Jurassic Dinosaurs belonging to the Order Theropoda
Authors: Marsh O. C.
Published: May 2009

The carnivorous Dinosauria form a well-marked order, which the writer has called the Theropoda, in his classification of this group. Although much has been written about these reptiles since Buckland described Megalosaurus in 1824, but little has really been made out in regard to the structure of the skull, and many portions of the skeleton still remain to be determined.
I.—Notes on the Geology of the Nile Valley
Authors: Dawson J. W.
Published: May 2009

Shortly after my arrival in Cairo, Dr. Schweinfurth, of that city, was so kind as to conduct me to a remarkable sea-terrace at the foot of the Mokattam hill, behind the tombs of the Caliphs, and stated, on the authority of Col. Ardagb, R.E., to be at an elevation of about 200 feet above the level of the sea, and which, I believe, was first described by Oscar Fraas. At this place a cliff of hard Eocene limestone, about 30 feet in height, has been perforated by Lithodomi, whose burrows are now filled with a grey calcareous deposit, and valves of a small species of oyster are also attached to the surface of the rock. The burrows resemble those of an ordinary Mediterranean species of Lithodomus, but I did not see the shells. The oyster has been described by Fuchs as a new species, under the name O. pseudo-cucullata; but, according to Dr. Schweinfurth, it does not seem distinguishable, except as a variety, from O. cucullata, Born. (=O. Forskali, Chemn.), of the Red Sea. Since the locality was observed by Fraas, Dr. Schweinfurth has discovered other shells in the crevices of the rock, more especially a Pecten, a Terebratula, and a Balanus, all modern species. The recent character of these shells and their mode of occurrence and state of preservation, oblige us, I think, to assign them to the Pleistocene, or at farthest the later Pliocene period, though I am aware that they have been regarded as Miocene.
VII.—The Permian-Trias Question
Authors: Irving A.
Published: May 2009

At the present stage of the controversy, it may seem, to those who have read carefully the paper of M. Marcou in the March Number of this Magazine, that very little remains to be said. Yet, however much it is to be regretted, it must be feared that insular prejudice still finds place with English geologists, and prevents them from seeing so clearly as they otherwise might do the full bearing of the evidence which we possess. I have thought, therefore, that at the present juncture it would be useful if one gave a short historical résumé of a few facts, taken partly from the introduction to Geinitz's great Monograph on the Dyas. The title of this work is of importance as an index of the stage at which the battle between the followers of Murchison in this country and the advocates of what we may call German views had arrived in the year 1862, when Geinitz's great work was published in Leipzig. Some years before this, Murchison had propounded his view of a “Palæozoic Trias” in his Siluria, and subsequently he went over a good portion of Central Germany with Prof. Morris, and on his return gave to the Geological Society his long paper on the Thüringen and Hartz country.
I.—Notes on the British Species of Ceratiocaris
Authors: Jones T. Rupert , Woodward Henry
Published: May 2009

Dr. Packard's observations on the structure of the Phyllopoda, and his comparative anatomical studies of allied living and extinct genera, supply the palæontologist with sound reasoning for referring the Phyllocarida to the Nebaliad type as a centre for a great group of obscure fossil forms, and as a starting-point for the Decapoda. His views have been referred to in some detail in the Geol. Mag. for August last, pages 349–352.
III.—On the Distribution of the Graptolithidæ in Time and Space
Authors: Herrmann Otto
Published: May 2009

It was indicated even by Murchison that the Graptolites constitute admirable characteristic fossils of the Silurian formation. Subsequent investigation has established that the group Graptolithidæ is essentially confined to the oldest fossiliferous formation. A single genus, the genus Dictyograptus, Hopk. (Dictyonema, Hall), occupies a remarkably exceptional position as regards its distribution in time. Formerly, indeed, this genus was separated from the proper or true Graptolites (Rhabdophora, Allman), and referred with some other genera (Dendrograptus, Hall, Ptilograptus, Hopk., Callogroptus, Hall) to the Campanularidæ but recently W. C. Brögger has very clearly shown that the genus in question differs very little from the true Graptolites, inasmuch as the most important parts of the latter, such as the sicula, and the hydrothecæ, have been detected in it. By this the Graptolithic nature of the genus in question is rendered very probable. Members of the genus Dictyograptus, Hopk., appear among the very oldest of known Graptolites; the genus maintains itself throughout the whole of the Silurian formation, while by its side new genera make their appearance, culminate and disappear. Even after the other Graptolites had long since disappeared from the ancient sea-fauna, this genus still lived on, for we find it occurring in the Devonian.
IV.—On the Fossil Sirenia in the British Museum (Natural History), Cromwell Road, S.W.
Authors: Woodward Henry
Published: May 2009

Among the vast additions which, during the past five years, have been made to the palæontological collections in the British Museum (Natural History), none probably possess greater interest to the naturalist and comparative anatomist than the remains of the very remarkable group of aquatic phytophagous mammals known as the Sirenia, of which the “Manatee” and the “Dugong” are the living representatives.
III.—On a Soda Felspar Rock at Dinas Head, North Coast of Cornwall
Authors: Fox Howard
Published: May 2009

Dinas Head is a promontory 4 miles west of Padstow, jutting out into the sea from Trevose Head, and separated from it by an isthmus about 100 feet above sea-level, which is washed clear of soil by the ground seas which sweep over it from the north. The headland is 165 feet above sea-level at its highest point, and is almost as broad from north to south as it is long from east to west. The base and foreshore of the headland appear to be entirely composed of greenstone containing much calcite. The microscope shows it to be probably an altered dolerite.
II.—A Criticism of the Astronomical Theory of the Ice Age, and of Lord Kelvin's Suggestions in Connection with a Genial Age at the Pole
Authors: Culverwell Edward P.
Published: May 2009

In the previous portion of this paper, which appeared in the January Number, I examined the form in which Croll presented the astronomical theory of the Ice Age and endeavoured to show how absolutely unsound his argument is. It is, however, at least as necessary to discuss the form in which Sir Robert Ball presents it; for much of the recent success of the theory, outside the school of modern geologists, was due to the weight naturally attached to the fact that a writer of Ball's scientific eminence believed he had so materially strengthened Croll's astronomical argument, that had Croll himself been aware of its full force, he would not have felt bound to call in such auxiliary agencies as a diversion of the Gulf Stream from its course. If, then, the theory, as presented by Croll, was able to win its way with such success among scientific authorities, it must surely be irresistible in the new and more powerful form. But it will be seen that, so far from strengthening Croll's position, Ball's statement weakens it very materially.
III.—The Evolution of the Brachiopoda
Authors: Crane Agnes
Published: May 2009

For many years I have been deeply interested in the general history of the Brachiopoda, and I have enjoyed the acquaintance, correspondence, and friendly encouragement of most of the eminent biologists and palæontologists who have devoted themselves to the elucidation of the complex structure of this class. Here I must name with reverence Davidson, long my friend and master; Barrande, of Prague; James Hall, of Albany; William King; Eugène Deslongchamps, the Norman naturalist; Suess, of Vienna; Friele, of Bergen; Morse, of Salem; and Dall, of Washington; “all honourable men,” and many others of the fin du siècle school, whose names will be noted in the sequel.
II.—The Evolution of the Brachiopoda
Authors: Crane Agnes
Published: May 2009

It is evident that neither Barrande nor Davidson, who maintained the opinions I have summarized till the last in their publications, were able to recognize the evidence deducible from a study of the Brachiopoda favourable to the theory of their evolution.
Proterozoic extensional deformation in the Mount Isa inlier, Queensland, Australia
Authors: Passchier C. W. , Williams P. R.
Published: May 2009

The earliest of four distinct phases of deformation recognized in the central part of the Proterozoic Mount Isa inlier involved brittle extensional faulting at shallow crustal levels. Extensional faulting produced stacks of imbricate fault slices, listric normal faults and characteristic tourmalinerich breccias. Structures belonging to this phase occur over a large part of the inlier and indicate an important phase of basin-forming crustal or lithospheric extension at 1750–1730 Ma. Late intense ductile deformation and tight folding of the imbricate systems destroyed part of these older structures, and obscures their existence in many parts of the inlier.
Fabric developments and the evolution of the Periadriatic Lineament in southeast Austria
Authors: von Gosen W.
Published: May 2009

The Periadriatic Lineament Zone which forms the boundary between the Eastern and Southern Alps in the Karawanken region of Austria has a complex history spanning the Variscan and Alpine orogenies. Variscan regional metamorphism and polyphase deformation followed by Late to Post Variscan intrusive activity with accompanying contact metamorphism affects a belt of structurally complex rocks referred to as the Eisenkappel Zone to the north of the lineament. Weak Early Alpine deformation in the Southern Alpine rocks can also be recognized in the Eisenkappel Zone. The Young Alpine intrusion of the Karawanken Tonalite was followed by lateral fault displacements associated with the formation of the Periadriatic Lineament. Late Tertiary sediments, caught up in the northward directed thrusting responsible for the uplift of the Karawanken chain, record the youngest deformation in the area.
A note on the regional context of the Loch Monar synform
Authors: Watkinson A. J. , Thiessen R. L.
Published: May 2009

The Loch Monar Synform folds the Sgurr Beag slide in the central northwest Highlands of Scotland. The east–west trend of the synform is oblique to the regional trend of the slide. However, when late-stage strain effects associated with superimposed folds on the synform are removed using computer techniques, the trace of the synform axial surface becomes perpendicular to the regional trace of the slide. The synform also becomes tighter and recumbent in attitude. The synform axis is parallel to strongly developed lineations. Folds of this generation appear to be localized in the vicinity of the slide. These observations suggest a model of folding associated with movement of the slide, followed by locking up of the slide and internal strain resulting in the superimposed folds and rotation of the synform.
The disequilibrium partial melting and assimilation of Caledonian granite by Tertiary basalt at Barnesmore, Co. Donegal
Authors: Kitchen D. E.
Published: May 2009

A regional Tertiary basaltic dyke swarm intensifies within a Caledonian granite at Barnesmore, Co. Donegal. Rapid heating along the contact of one (possible feeder) dyke resulted in disequilibrium partial melting of granite wall-rock and the generation of a range in melt composition by the in situ melting of feldspar. The compositional variability of the melt is preserved in a glass containing feldspar spherulites and other quench phases which suggest rapid cooling. During partial melting the trace elements, Rb, Sr, and Ba were mobile and have been concentrated in glassy melted granite close to the contact of one dyke. The textures, mineralogy and geochemistry of dolerite in two dykes indicate localized bulk contamination and mixing with melted granite. This had a particularly marked effect on the crystallization of pyroxene and resulted in a wide range in mineral composition reflecting the degree of contamination. The intensification of a regional dyke swarm in well-jointed granite might control the siting of some major intrusive centres. Granite melted and mixed with basaltic magma may contribute to the evolution of granites in such centres.
Westphalian alluvial plain sedimentation, Isle of Arran, Scotland
Authors: Kirk M.
Published: May 2009

Facies analysis suggests that Westphalian (Upper Carboniferous) Coal Measure sequences on the Isle of Arran, Scotland, were deposited in a proximal alluvial plain environment close to the basin margin. Detailed examination of well exposed coastal sections has revealed the existence of six laterally and vertically interrelated sedimentary facies. Facies 1 to 3 are interpreted as fluvial channel deposits. Low sinuosity multistorey (facies 1), low sinuosity vertically accreted (facies 2), and rare high sinuosity laterally accreted channel deposits (facies 3) are developed. Associated overbank sediments comprise the deposits of crevasse splays (facies 4), flood plains (facies 5) and shallow lakes (facies 6). In terms of the spatial distribution of facies, a relatively high proportion of fluvial channel and floodplain deposits (facies 2 and 5) occur in the more proximal sequence at Laggan compared with the more distally located sequence occurring at Corrie. Palaeocurrent measurements from fluvial channel sandstones indicate that sediment source areas and the Westphalian basin margin lay to the north and northwest. Down palaeoslope towards the southeast, normal coal-bearing Westphalian sediments formed penecontemporaneously on the Scottish mainland in Ayrshire.

A sedimentological model is presented for the proximal non-coal-bearing Westphalian sequences of Arran. This model can explain the differences observed between the Arran sediments, and contemporaneous normal coal-bearing Westphalian sediments of the Scottish mainland.
Quartz-spessartine metasediments (coticules) and their protoliths in North Wales
Authors: Bennett M. A.
Published: May 2009

Thin beds and small pods of quartz-spessartine metasediments (coticules) occur in pelites of the Gamlan Formation (Cambrian) of the Harlech Dome. The original microfabric of these sediments has been largely destroyed by recrystallization under low greenschist facies conditions. The quartz-spessartine pods occur throughout the pelites and appear to have formed by the metamorphism of diagenetic Mn-carbonate concretions. The thin beds of quartz-spessartine rock appear to have formed by the metamorphism of a protolith which was deposited rapidly and repeatedly over a wide area. Although there is no direct evidence of the nature of this protolith, the presence of altered Mn-carbonate-rich tuff beds in anchizonal mudstones of similar age in the St Tudwal's Peninsula suggests that the bedded quartz-spessartine rocks are, in fact, metamorphosed Mn-carbonate-rich tuff units. Both the bedded and podiform quartz-spessartine metasediments appear to have formed by reaction between clay minerals and Mn carbonates of earlier diagenetic origin.
Lower Cambrian anabaritids from south China
Authors: Conway Morris S. , Menge Chen
Published: May 2009

Anabaritids are a distinctive group of early skeletal fossils, with tri-radially symmetrical tubes. They occur in the earliest Cambrian deposits, and seem to be especially characteristic of the Tommotian strata and putative pre-Tommotian units (e.g. Manykay horizon). A detailed redescription ofAnabarites rotundusQian from near Kuanchuanpu, Shaanxi Province emphasizes the degree of morphological variation. New data on shell composition suggest a bilayered structure, the outer unit composed of fibres parallel to growth lines, overlying a distinctive inner lamella with a chevron ultrastructure. Tentative evidence for anabaritids possibly being operculate is presented, the putative operculum being a simple convex disc. More poorly preserved anabaritids from the Yangtze Gorges (Hubei Province) and Meishucun (Yunnan Province) are referred toA. trisulcatus. All these Chinese occurrences of anabaritids are consistent with a lower Tommotian age of the associated faunas, but reliable and precise correlations with other Precambrian-Cambrian boundary sections remain inconclusive.
Lower Cambrian coeloscleritophorans (Ninella, Siphogonuchites) from Xinjiang and Shaanxi, China
Authors: Morris S. Conway , Chapman A. J.
Published: May 2009

Ninella tarimensisfrom the Lower Cambrian Yurtus Formation of western Xinjiang, China, is shown to be a relative of the halkieriids and siphogonuchitids. These are known principally from dispersed sclerites, presumably secreted by slug-like organisms that were an abundant component of the Cambrian benthos. The sclerites ofN. tarimensisare relatively small, strongly recurved and usually possess an upper surface ornamented with transverse sculpture. The lower surface is more or less smooth and is joined to the upper surface via steep faces that may be grooved. The apertural region is quadrate in outline and bears a circular foramen.Ninellais fairly widespread and is known from elsewhere in China (Guizhou and Shaanxi Provinces) and from Kazakhstan. A brief description of the siphogonuchitid scleritome is also presented, based on dispersed sclerites and shells from the Lower Cambrian of Shaanxi Province, China. Formal synonymy of the sciotaxaSiphogonuchites, Dabashanites, Lopochites, andMaikhanellaasSiphogonuchitesis proposed.
Quaternary tectonics at the eastern border of the Bohemian Massif: new outcrop evidence
Authors: Leichmann Jaromir , Hejl Ewald
Published: May 2009

Recently, an outcrop with clear evidence for Quaternary faulting has been discovered in the eastern part of Bohemian Massif, 25 km southwest of Brno (Moravia, Czech Republic). Basement serpentinite, fluvial gravels, loess and young scree are affected by a steep NNW–SSE trending fault. The geological situation of the outcrop is described for the first time in this article.
The Pan-African Toro Complex (northern Nigeria): magmatic interactions and structures in a bimodal intrusion
Authors: Déléris J. , Nédélec A. , Ferré E. , Gleizes G. , Ménot R.-P. , Obasi C. K. , Bouchez J.-L.
Published: May 2009

The Toro Complex is one of the Pan-African Older Granites of Nigeria, first described as a reversely zoned pluton made of a central dioritic mass surrounded by a broad granitic rim. It has been thoroughly reinvestigated both from the petrographic and structural points of view, with the help of systematic anisotropy of magnetic susceptibility (AMS) measurements. The granite main body is a hornblende–biotite porphyritic monzogranite characterized by an early submagmatic fabric displaying a concentric pattern of foliations and west plunging lineations (stage 1). This fabric is overprinted by a later one due to solid-state strain along north-south subvertical dextral shear zones (stage 2). In the vicinity of the diorite, an evengrained granite displays magmatic structures that are contemporaneous with this strike-slip event. The diorite–granite contact is a complex zone where field, petrographic and geochemical data enable recognition of the effects of mixing and mingling between a mafic and a felsic magma. Tonalites cropping out within this contact zone are interpreted as hybrid rocks. The reverse zonation of the diorite itself is also the result of some hybridization process. Magmatic interactions mainly resulted from in situ infiltration of granitic liquid into the dioritic mass. The detailed history of this bimodal intrusion began with the emplacement of the granitic magma acquiring a first stage fabric. Before full crystallization of the granitic core, intrusion of the dioritic magma permitted reheating of the granitic magma that then crystallized with specific structural characters. The second stage structures, whether characterized by magmatic fabric near the diorite or by solid-state strain features in north–south shear zones elsewhere in the granite, are related to late Pan-African dextral strike-slip tectonics in the basement of northern Nigeria. The bimodal Toro Complex is therefore considered as a late Pan-African syntectonic pluton.
Low-pressure, high-temperature metamorphism in a compressional tectonic setting: Mary Kathleen Fold Belt, northeastern Australia
Authors: Reinhardt J.
Published: May 2009

The Mary Kathleen Fold Belt in northeastern Australia consists of highly deformed, Mid-Proterozoic sedimentary and volcanic sequences as well as intrusives, which were metamorphosed under low-pressure, high-temperature conditions. In the light of current controversy on tectono-thermal settings of low-pressure metamorphic terrains, the interrelations of progressive deformation and metamorphism have been closely examined. Remarkably, there is no direct evidence for syn-metamorphic extensional deformation nor is any significant intrusive activity recorded.

Syn-metamorphic structures indicate lateral, bulk coaxial shortening of at least 50–60%. Tight upright folds, pervasive axial planar fabrics, undulating fold axes, and a vertical mineral lineation characterize this deformation. The metamorphic textures, particularly those in andalusite- and/or cordierite-bearing schists, reveal the sequential growth of metamorphic minerals that was synchronous with progressively increasing bulk rock strain. The corresponding metamorphic reactions constrain a prograde P–T path segment that crossed the andalusite and sillimanite stability fields while temperature and pressure increased. After reaching the metamorphic peak, the region cooled down near-isobarically, before major decompression occurred. The prograde–retrograde P–T path forms a complete anticlockwise loop.

Due to the lack of evidence for crustal thinning and large-scale magmatism in the upper crust, alternative models are discussed in order to explain the transient high geothermal gradient. These are in particular convective thinning of the lithospheric mantle and fast decompression of crustal sections, possibly linked to tectonic processes preceeding the low-pressure/high-temperature orogenic event.
Chemistry and petrological evolution of the Lastarria volcanic complex in the north Chilean Andes
Authors: Naranjo José A.
Published: May 2009

The Lastarria volcanic complex, along the northern Chile–Argentina border, includes three morphostructural components: Southern Spur, Lastarria (the highest cone, 5697 m) and Negriales (a geographically associated lava field, 5.4 km3). Petrographically, the Lastarria complex consists of pyroxene andesites and pyroxene–amphibole dacites. The whole-rock geochemistry shows a bimodial silica variation between 57 and 68%, with peaks at 59–60% and 61.62% SiO2. Petrographie and chemical data indicate different magmatic sources for Lastarria and Negriales. Whole-rock geochemistry can be explained by crustal contamination and crystal–liquid fractionation, with differences in storage times in magma chambers being a major controlling factor. Strong textural, mineralogical and chemical evidence for magma mixing, shortly before explosive eruptions at Lastarria, suggests that this process may have triggered the violent eruptive volcanic activity which characterizes the latest stages of the main cone. Abundant bombs of banded clear pumice and dark scoria in pyroclastic flow deposits are the texturally heterogeneous products resulting from incomplete mixing homogenization.
The ichnofauna of the Skiddaw Group (early Ordovician) of the Lake District, England
Authors: Orr Patrick J.
Published: May 2009

Deep-marine strata of the Skiddaw Group, deposited in high southerly palaeolatitudes on the northern margin of Eastern Avalonia in the early Ordovician, contain a diverse ichnofauna dominated by examples of fodinichnia. This includesAlcyonidiopsis pharmaceus, several ichnospecies ofChondrites, Dictyodora zimmermani, Glockerichnus radiatus, Gordia marina, Ixalichnus enodius, two or possibly three ichnospecies ofPhycodes, Planolites montanus, Volkichnium volki, an ‘arthropod-produced? repichnion’, ‘paired pits’, ?Gordiaaff.marina, ‘thinly-walled, looping, burrows’ and burrows ofPlanolites/Palaeophycusaffinity.Stellascolites radiatusEtheridge, 1876 is reassigned to the ichnogenusGlockerichnusPickerill, 1982 asGlockerichnus radiatus(Etheridge, 1876).

Several of the ichnotaxa are present in other ichnofaunal assemblages of early Ordovician age which were also emplaced at high southerly palaeolatitudes. The relatively high diversity of this ichnofaunal assemblage supports suggestions that models of the rate at which the deep-marine environment was colonized during the early Phanerozoic are in need of revision.
Bedform movement in a marine tidal delta: air photo interpretations
Authors: Harris P. T. , Jones M. R.
Published: May 2009

Morphological changes in bedforms composing a tidal delta at the northern entrance to Moreton Bay, Queensland have been studied by examining aerial photographs spanning a 26-year time period. The aerial photographs show the movements of 51 different sand-bank crestlines, and the morphological characteristics of both sand banks and sandwaves. From the orientation of sandwave crests to the sand-bank crestlines, zones of ebb- and flood-dominance in sand-transport direction are distinguished. The migration directions of the sand banks are predicted by considering the cross-sectional asymmetry of the sand banks together with their adjacent ebb/flood zones of net sand transport. The reliability of the predictions is tested by comparisons with sequential air photo data. When applied to 53 bedforms, the predictions achieved a high success rate, with 45 predicted migration directions matching those observed on the sequential aerial photographs. Bedform movement can be predicted, therefore, for any water depths in which submarine bedforms can be clearly seen on aerial photographs (< 10 m).

Based upon their mobility, sand banks are classified into three categories: dynamic sand banks, which change quickly (within 2 years) and which have migration rates that are non-uniform along the bank crestline; progressive sand banks, which change slowly (from 2–10 years) and have migration rates that are uniform along their crestlines; and immobile sand banks, which change only over time intervals which exceed 10 years. Changes in sand-bank morphology occur by migration of the crestline together with growth and decay, and are considered to be linked with changes of larger ebb- and flood-dominant zones of net sand transport. The three different sand-bank types are characterized by distinctive heights, crestline lengths and wavelengths. They occur in different locations within Moreton Bay, possibly related to distance from external sand supplies and to relative tidal current and surface wave energy levels.
Alluvial channel bank-collapse phenomena in the Old Red Sandstone Hitra Group, Western Central Norway
Authors: Bøe R.
Published: May 2009

The Old Red Sandstone (ORS) on the island of Hitra forms an approximately 1350 m thick succession of alternating continental mudstones, sandstones and conglomerates of possibly latest Silurian to Devonian age. Within the middle part of this succession, just above a major, scoured surface, a spectacular slump feature was observed. The phenomenon is interpreted as a unit of overbank/channel bank mudstones which, because of undercutting and liquidization, caved into a low sinuosity river channel. The Hitra sequence is the only one in the Norwegian ORS where such phenomena have as yet been identified.
Studies of tooth implantation in fossil tetrapods using high-resolution X-radiography
Authors: Fraser N. C. , Shelton C. G.
Published: May 2009

The concept that reptilian tooth implantations fall neatly into a number of separate categories which can be used in phylogenetic studies is called into question. The use of microfocal X-radiography in preliminary studies of reptilian dentitions reveals that, at least in sphenodontids, there is no clear distinction between acrodonty and pleurodonty. Although the technique is used here specifically in connection with microvertebrates, it may have considerable potential in evaluating internal structures in a wide range of fossils.
Upper Ordovician cliefdenellids (Porifera: Sphinctozoa) from China
Authors: Webby B. D. , Baoyu Lin
Published: May 2009

Aporate sphinctozoan sponges of the Family Cliefdenellidae Webby, 1969, are described for the Upper Ordovician (Ashgill) of northern and northwest China, including the new genusKhalfinaeaand a new speciesK. shaanxiensis. They are characteristic cliefdenellids with conico-cylindrical and branching forms, a single central tube defined by a thickened, sieve-like endowall, and a filling of irregularly orientated astrorhizal canals, vesicles and thickened (?trabecular) tissue

Taxonomic relationships of the other cliefdenellids are also discussed. The conception of the genusCliefdenellaWebby, 1969, is restricted to those forms with massive, hemispherical to explanate form and multiple, bundled vertical excurrent canal-clusters, and the new genusRigbyetiais introduced to include conico-cylindrical and branching forms with a central tube composed of a single, vertical, bundled, excurrent canal-cluster

In terms of their biogeographical record, the cliefdenellids have a restricted distribution in the Upper Ordovician (middle Caradoc-Ashgill) ‘fold-belt’ successions of the Palaeo-Pacific region (eastern Australia, Alaska and northern California) and in Asia (northern China, and in the Chinese and Soviet Altai)
Ground melting and ocellar komatiites: a lead isotopic study at Kambalda, Western Australia
Authors: McNaughton N. J. , Frost K. M. , Groves D. I.
Published: May 2009

Stratigraphically and geographically restricted ocellar komatiite flows at Kambalda, Western Australia, appear to represent the products of ground melting of sulphidic sediments by komatiites in lava channels that localized the Fe–Ni–Cu sulphide ores. An immiscible sulphide liquid formed and gravitationally separated from the melted sediment (xenomelt), the resultant buoyant silicate liquid being partly or wholly assimilated by the turbulently convecting komatiite magma. Rarely, the xenomelt gravitationally migrated to the top of flows, and overflowed into the less turbulent lava levees where it collected to form a separate layer overlying a komatiitic layer within a single flow. There was selective preservation of the hybrid felsic layer, as an upper ocellar unit within an ocellar komatiite flow, in lava levees flanking lava channels. The ocellar unit is enriched in elements previously concentrated in the sediments, and shows U–Th–Pb isotopic systematics akin to the underlying sediments. Moreover, the partitioning relationships of U and Pb between the immiscible xenomelt and sulphide liquid enhances the range of U/Pb ratios for components of the ocellar unit, thus allowing sufficient spread of modern uranogenic Pb isotopic ratios to form isochrons, albeit imprecise ones. The range and similarity of model Th/U data from these flows (2.8−3.9) and adjacent sulphidic sediments (2.3−4.4; mostly 2.8−3.9) contrasts with the generally invariable Th/U within Kambalda ultrabasic–basic flows (3.6−3.9), and further supports the ground-melting hypothesis.
Crack–reaction veins from the Hodgkinson Formation, North Queensland, Australia
Authors: Forde A. , Davis B. K.
Published: May 2009

Thin, subplanar or parallel-sided syntectonic quartz veins from the Hodgkinson Province, North Queensland, Australia contain mica inclusions that are identical to wallrock mica textures. These ghost textures can only be produced by incomplete replacement of the wallrock by quartz. The planar form of the veins indicates that there was a planar control on their formation. We propose that the veins formed around syntectonic fractures that localized silica micrometasomatism of the fracture wall. The formation of the veins can be explained by a model which involves fracture of the wallrock, reaction between the fracture wall and the ambient metamorphic fluid and eventual sealing of the fracture by precipitation from the fluid. The new vein is then a locus of further fracture. Replacement of wallrock micas occurs via a two-stage process where biotite is replaced by muscovite, which is in turn replaced by quartz. We propose the term crack–reaction to describe the resulting cyclic process because it can be compared with the crack–seal model of vein formation. Crack–seal and crack–reaction are different only in the relative amounts of metasomatism and precipitation that occur subsequent to fracture and can be envisaged as end members of a more general vein-forming process.
Physical properties of carbonatite magmas inferred from molten salt data, and application to extraction patterns from carbonatite–silicate magma chambers
Authors: Wolff J. A.
Published: May 2009

Little is known about the physical properties of carbonatite magmas, making it difficult to predict dynamic behaviour in carbonatite-bearing magmatic systems. The viscosity of calcium-rich carbonatite magma is approximately estimated from molten salt data to be 0.1 Pa s at 700–800°C, while density is estimated at 2.3−2.5 × 103 kg m−3. The corresponding values for natrocarbonatite are 0.01 Pa s and 2.0−2.1 × 103 kg m−3. It is thus possible for carbonatite to be negatively buoyant with respect to some silicate magmas. The surface tension in air of carbonatite magmas is estimated at 0.25 and 0.21 N m−1 for Ca-carbonatite and natrocarbonatite respectively. Knowledge of the interfacial tension between carbonatite and silicate liquids is critical before the formation and behaviour of silicate–carbonatite emulsions can be properly understood. Interfacial tension is constrained to < 0.09 N m−1 by the application of multiphase drop theory to experimentally-produced textures, and this value receives some support from geological observations. The mechanics of extraction from layered carbonatite-silicate magma chambers are briefly examined using the recommended density and viscosity values and the equations of Blake & Ivey (1986); the degree of eruptive mingling is dependent on which liquid was uppermost in the chamber.
Pliocene–Pleistocene fluvial/wave-dominated deltaic sedimentation: the Pamisos delta, southwest Peloponnesus, Greece
Authors: Zelilidis Abraham , Kontopoulos Nikolaos
Published: May 2009

A fluvial /wave-dominated delta was formed during late Pliocene times in southwestPeloponnesus, influenced by NNW—SSE and ENE—WSW trending faults. The depositional patternremained unchanged through early Pleistocene times, when the pre-existing active faults with WNW—ESE extension were combined with an eastward asymmetrical subsidence of the graben. Inthe deltaic environment, marshes, lakes and lagoons were created in the western parts, whereas largequantities of sediments were deposited in the central and eastern parts adjacent to basin marginsof steeper relief.

This study combines grain size parameters, total organic matter, carbonate and clay mineralogyand structural analysis to: (a) determine the pattern of sedimentation in sub-environments and (b)create a fluvial/wave-type deltaic depositional model, and distinguish between delta-plain, delta-front and pro-delta environments. The Pliocene-Pleistocene, fluvial/wave-dominated delta model inthis study can be used to predict deltaic sedimentation in analogous basins.
The volcanic history of the southwestern part of the city of Naples
Authors: Cole Paul D. , Perrotta Annamaria , Scarpati Claudio
Published: May 2009

The southwestern part of Naples was the site of small volume volcanic activity prior to 12000 y B.P. Lava domes and possibly a lava flow were erupted during the earliest period. Explosive activity followed and produced pyroclastic sequences that are the proximal deposits of tuff cones within the city and at its southwestern extreme. The explosive activity was complex but predominantly phreatomagmatic. As the volcanic activity more than 12000 y B.P. in western Campi Flegrei shows a similar evolution from effusive to explosive, it is suggested that a large volcanic field ‘Paleoflegrei’, encompassing the western part of the city of Naples, existed prior to emplacement of the Neapolitan Yellow Tuff. The Neapolitan Yellow Tuff eruption about 12000 y B.P., from a vent in Campi Flegrei, produced widespread deposits up to 150 m thick that blanketed the area of the city of Naples, although the present day topography is strongly influenced by the pre-Neapolitan Yellow Tuff centres. Following the Neapolitan Yellow Tuff a small explosive eruption occurred in the bay of Chiaia, immediately south of the city, and results in the possibility of future eruptions within the city of Naples, outside the confines of Campi Flegrei and Vesuvius.