The eastern Nankai accretionary prism toe was surveyed to evaluate the nature and deformation of its frontal thrust. According to the determined porosities and yield strengths, turbidites were successively buried down to depths of 250–300 m before accretion, and were then exposed at the prism toe by uplift along the Tenryu frontal thrust during 3.4–1.98 Ma. Consolidation tests provided reasonable estimates of burial depth and, when combined with exposed sediment dates, yield prism toe uplift rates of 0.74–2.27 m ka–1. The displacement along the frontal thrust is estimated to be 500–900 m and the slip rates are 1.47–4.55 m ka–1, corresponding to the highest class of active faults on land in Japan. During the surveys of the Tenryu frontal thrust zone, we discovered a new active fault scarp that was several tens of centimetres high, interpreted to be a protothrust located c. 100 m south of the frontal thrust. This scarp is associated with chemosynthetic biocommunities. The thrust might potentially be the result of displacement during the East Nankai (To-Nankai) earthquake (Mw 8.1) in 1944. These lines of evidence indicate that the Tenryu frontal thrust is still active and that displacement along the thrust might induce a tsunami during future Tokai or To-Nankai earthquakes.

Whidborne gave a composite description of certain specimens from the Upper Devonian of Pilton and other localities which he grouped together and ascribed to the Carboniferous species P. (Buxtonia) scabriculus Mart. (Whidborne, 1897, 170, pi. xx, figs. 16–18, pi. xxi, fig. 12), but he considered that it was difficult to distinguish some of them from those which he ascribed to Strophalosia productoides. We cannot agree with his reference of any of them to Martin's Carboniferous species. The best preserved and first example [H. 286] which he figured (1897, pi. xx, fig. 16) is a pedicle-valve from “Smoking House Lane”. It has a transversely subquadrate shape with subrectangular cardinal angles not produced; the body is strongly arched longitudinally but only moderately convex transversely, and it has a weak median longitudinal depression, but descends steeply on each side to the smalt ears; it is covered by regular continuous rounded costae of equal size, about fifty in number, some of which bifurcate at about one-third to two-thirds their length, and very few of them show any small swellings on their course as in P. scabriulus; a few faint narrow concentric rugae are traceable on the posterior third of the body producing weak coarse reticulation; the umbo is very broad, rounded and incurved, projecting over the hinge-line; the ears, which are much depressed but not sharply marked off from the body, are triangular in shape and are crossed by a few narrow concentric rugae which bifurcate somewhat irregularly before reaching the hinge-line; a few large coarse spinose tubercles or spine-bases lie near the junction of the body with the ears. This pedicle-valve is sufficiently preserved to indicate a distinct species, for which the name porteri is proposed.

Previous History.—In 1892 Professor Carl W. S. Aurivillius published his well-known paper “Ueber einige ober-silurische Cirripeden aus Gotland” (Bihang Svenska Vet.-Akad. Handl. Bd 18, Aid. IV, No. 3). Besides the remarkable specimen from the Ludlovian Pterygotus bed of Wisby, to which he gave the name Pollicipes signatus, and a supposed fragment of a scutum, which he called P. validus, Professor Aurivillius described a number of “kurze, mehr oder weniger cylindrische, mit Schuppen bedeckte Bildungen”, which he regarded as the peduncles of a cirripede and referred provisionally, in the absence of any trace of a capitulum, to Scalpellum. Though all the specimens (except possibly of S. cylindricum) came from a single stratum, bed c of Lindström, probably contemporaneous with our Wenlock Shale, and though the majority were found in a single locality, Djupvik in Eksta, still Professor Aurivillius considered that he could with certainty distinguish the following seven species:

The specific name of this form is not in doubt, but its authorship is less securely determined. The species Terebratula cuneata was proposed by both Dalman (1828, 141, Tab. vi, figs. 3a–c)and Hisinger (1828, 220, 239, Tab. vi, fig. 5) in the same year, and the first time each author mentions the name, he ascribes it to the other. Each account is accompanied by figures, and there appears to be no ruling of the International Commission on Nomenclature that would settle the authorship in such a case. Dalman's account, however, appears in the volume for 1827, though the title page bears the imprint 1828, and such a choice of authorship agrees with alphabetical priority and with the usage of most subsequent palaeontologists.

In August, 1928, the writer made a study of the freshwater solution caverns of Bermuda, and their relation to the general geology of the islands has been productive of some observations and conclusions. Various kinds of obligations have been incurred in connection with this study; since it is intended that more complete publication will follow none of these obligations will be acknowledged here. The work was carried on by financial support. extended through the Division of Geology of Harvard University.

Quantitative methods of X-ray fluorescence analysis have been employed to the determination of Pb, Zn, Ni, As, Rb, Ce and Y, in soils of the Teign Valley of SW Devon. The results enable a comparison to be made of the ore metal and non-metal anomalies found, and demonstrate the applicability of non-metals as lode indicators.

Of this I have seen only two specimens. One of them, slightly longer than the other, measures 3½ inches in length up to the commencement of the caudal fin, which is deficient in both; the greatest depth of the body ½½ inch, the length of the head nearly the same. The dorsal fin is opposite the interval between the ventral and the anal; both dorsal and anal are triangular acuminate in shape, with delicate rays which at first are somewhat distantly articulated, the joints being ornamented with one or two longitudinal sulci. The pectorals are not seen in either specimen, but the smaller of the two shows a well-preserved ventral, which is pretty large, and acuminate in shape.

The Junction of the Chalk with the Lower Tertiaries is nearly always marked by the presence of green-coated flints; and in East Kent, where the Thanet Sands rest on the Chalk, numerous junction-sections are exposed, exhibiting the peculiarities which I now lay before you.

The English Bathonian contains a rich foraminiferal fauna composed largely of Lagenidae. The succession of foraminifera is as yet only partially revealed, but some faunal changes between the Lias and Bathonian are apparent, and four faunules have been distinguished in the Bathonian. In Dorset and the vicinity of Bath the faunules occur in the same order of superposition. In comparing the English Bathonian foraminifera with those in the German section the present data suggest that a number of species range higher in England than in Germany.

Considerable difficulty has been felt in accounting for the transport of the Wastdale Granite Boulders across the Pennine chain to the east. Professors Harkness and Phillips, Messrs. Searles Wood, jun., Mackintosh, and I presume all who have written on the subject, agree that these blocks could not have been transported by land-ice. The agency of floating ice under some form or other is assumed by them all.

These papers arise from the conference in Bristol, England, of the above international Working Group, which was held in the University of Bristol conference centre from 9–13 May, 1983. Forty-five persons attended; thirty-two were members of the Working Group (about a third of the total membership which is drawn from about twenty countries in many parts of the world from Australia to Argentina and from Korea to western Canada.)

In September last, I drew the attention of the readers of the Geological Magazine (Decade III. Vol. II. pp. 412–425) to a singular group of vegetable-feeding aquatic animals, the Sirenia, represented at the present day by two genera, Manatus and Halicore, and by at most six species, three or four of which are probably only varieties. A peculiarity of this group of animals is that whereas the two living genera are distributed in the subtropical regions East and West of the African continent, and to its rivers and opposite coasts, the ancestors of the Halicore and Manatee (the Halitherium, Felsinotherium, and some ten other fossil genera of Sirenians) probably intermingled and extended 30° further north than at present from the West Indies and Carolina through England, Belgium, France, Germany, Italy, and North Africa, whilst Rhytina, the largest of them all, only became extinct 100 years ago on the shores of Behring's Island, Kamtchatka. The evidence which the fossil remains of Sirenia afford of a more northerly geographical extension of subtropical mammalia in Tertiary times, is abundantly confirmed by other genera, to one of which only, the Hippopotamus, I will here refer.

Near Kildale, a small village on the North Yorkshire and Cleveland Railway, not far from the source of the river Leven, a railway cutting close to the station shows, in descending order, the following section.

These specimens were collected in Socotra, near the coast, by Colonel M. Gosset, and were sent to Prof. Rupert Jones. By the kindness of Prof. Bonney I have been allowed to carry on the examination of the rocks, at University College, in connection with the Somali specimens already described.

Zoœcia separated by a distinct furrow, which passes into a deep crevice at the junction points, widely rounded below but tapering very considerably and almost to a point above, with areas of the same shape and upright rounded side walls thickening considerably below, and often developing something of an internal front wall; average length of area 28 mm., breadth 2 mm., but marginal zoœcia often run much larger.

Among the very few known instances of fossil hydroids, the genus Hydractinia must be included. Under the name of Cellepora echinata, M. Michelin has described a fossil from the Subapennine group of Asti, and from the Superior Fallunian of Bordeaux and Dax (Michelin, Icon. Zooph., p. 74, pl. xv., fig. 4). M. Fischer has drawn attention to the fact, that the Cellepora echinata of Michelin is really a Hydractinia encrusting a Murex or a Nassa, while he has himself added another fossil Hydractinia from the Upper Greensand of Mans (Fischer, Bull, de la Soc. Géol. de France, 2me sér. t. xxiv., p. 689). This he found in the collection of M. Alc. d’Orbigny, where it encrusted numerous specimens of Natica tuberculata, d’Orbig., from that formation. M. Fischer has assigned to this species the name of Hydractina cretacea, while to Michelin's species he has given that of Hydractina Michelini.

In his article on septarian structure in the March number of the GEOLOGICAL MAGAZINE Dr. A. Morley Davies seems to call for further light upon the subject, hence the following is offered. The writer became convinced of the fallacy of the current teaching concerning the formation of concretions with cracked interiors and of septaria more than thirty years ago, and has so taught in his classes ever since. In 1902 he published a paper on “Concretions and their Geological Effects”, which presented facts which virtually demonstrate that the cracking is due to the expansion of the exterior rather than by a contraction of the interior, as Dr. Davies has also concluded.

The mid-Oligocene sediments forming the Beacon Cottage Farm Outlier at St Agnes, Cornwall, have a stratigraphical and geomorphological importance which is out of all proportion to their modest residual bulk (some 300000 m3). During 1986–8 61 holes were sunk into the area surrounding Beacon Cottage Farm; many penetrated the Palaeozoic floor beneath the outlier. Collectively, these show that the outlier mostly covers rotten granite and Killas. The sub-Oligocene unconformity is uneven and varies in altitude by at least 20 m. The local Bovey Formation succession comprises two members: Basal Sand, which is often pebbly, and sandy silts, known commercially as Candle Clay, the whole totalling a maximum of 8.9 m. There is indirect evidence either that slopes on the rotted Palaeozoic floor locally exceed 45° or that several post-mid-Oligocene faults affect the outlier. We conclude that the Beacon Cottage Farm sediments probably represent aeolian, colluvially and fluvially redistributed rotten rock residues, formed locally during a break in the long period of late-Palaeogene subtropical weathering and pediplanation. The outlier is considered in relation to the geomorphological evolution of the Cornubian Massif.

The South Qinling block, a segment of the Yangtze craton involved in the Qinling–Dabie orogen, is critical for understanding the tectonic evolution of eastern China. However, the tectonic setting of the South Qinling block and the northern margin of the Yangtze block during middle Neoproterozoic time has long been the subject of debate, with two distinctly different models (continental rift or volcanic arc) proposed. Here, a comprehensive study of zircon U–Pb geochronology and geochemistry has been carried out on the Chengwan granitic pluton from the Suizao terrane in the South Qinling block. The granites are monzogranite and syenogranite in lithology, and are mainly composed of potash feldspar, quartz, plagioclase and biotite. This suite has long been regarded as a Palaeozoic magmatic pluton, but zircon U–Pb ages of 809 ± 9 Ma and 816 ± 4 Ma are obtained in this study. The granites are metaluminous to strongly peraluminous with high alkali contents, and exhibit highly fractionated features, including high SiO2, low Zr/Hf ratios, rare earth element tetrad effects and enrichment of K and Rb. They show Hf–Nd isotopic decoupling, which may be genetically related to their petrogenetic process. Based on the geochemical features and the positive εHf(t) values of the zircons, it is indicated that the granites may have been derived from partial melting of juvenile tonalitic rocks by biotite breakdown under fluid-absent conditions. The Chengwan granite geochemically belongs to the A2-subtype granites, suggesting that it might have formed in a post-orogenic tectonic setting. The highly fractionated A-type granite in this study may represent extensional collapse shortly after the collisional events in the South Qinling block, and thus indicate a tectonic regime switch, from compression to extension, as early as middle Neoproterozoic time. Integrating our new data with documented magmatic, metamorphic and sedimentary events during middle Neoproterozoic time in the region may support a continental rift model, and argues against arc models.