Marine invertebrate borings are very rare in crystalline rocks, providing evidence of particular strategies producers use to colonise these unfavourable substrates. In the Sorbas Basin (Almería, southern Spain), Upper Miocene transgressive successions contain blocks of metamorphic and igneous rocks of the Nevado–Filabride Complex of the Betic Cordillera. Ichnological analysis of the embedded blocks shows the presence of two types of macroborings located in gneiss boulders, revealed to be an extraordinary case worldwide. The most abundant are regular hemispherical depressions ascribed reservedly to the well-known, mostly bivalve boring Gastrochaenolites. The second one is a pouch-like depression, tapering downward, elliptical in outline, and clearly different to other non-circular-in-outline, pouch-shaped macroborings. Thus, a new ichnogenus and ichnospecies Cuenulites sorbasensis has been defined. According to the overall shape, an endolithic or semi-endolithic bivalve using chemical means to bore is suggested as the tracemaker. Colonisation could be determined by sea-level coastal dynamics, with decreasing energy during advancing transgression allowing boring, which was then stopped due to supply of fine-grained sediment that killed the borers.

16 samples of Ordovician basic volcanic rocks of the South Connemara Group, which abut the southern side of the metamorphic rocks of the Connemara massif in western Ireland, have been analysed for both major and trace elements. Although subject to low grade regional metamorphism and subsequently hornfelsed by the Galway Granite (400 Ma), their immobile element contents do not appear to be significantly disturbed. These elements characterise the metabasites of the South Connemara Group as ocean floor basalts having their origins in a marginal basin. The Skird Rocks Fault, separating the South Connemara Group from high grade metamorphic rocks of the Connemara massif, is consequently regarded as the northern margin of the vestiges of the lapetus Ocean which can be traced into, and along, the Southern Uplands Fault.

Contaminated igneous rocks [1, pp. 177–83; 2, pp. 446–86; 3, pp. 128–46] are those resulting from the solidification of a magma which has been modified by reaction with xenoliths, usually of sedimentary origin. The Younger Gabbro masses of North-East Scotland provide what are probably the best examples of this phenomenon yet known, and their investigation will doubtless throw some light upon current petrogenetic theory.

The Chalk of England contains three main Hexactinellid faunas, of Lower Cenomanian, Middle and Upper Turonian, and Lower Senonian to Maestrichtian age respectively. The third is also represented in Ireland. A number of minor faunal changes can also be recognized. The three main faunas have little in common, and their relationship is not evolutionary; the changes appear to be due to migrations. By analogy with modern forms, this is likely to reflect changes in the pattern of current circulation in the Upper Cretaceous ocean.

The historical development of the stratigraphic nomenclature of the Llandovery of north Connemara is described. The lowest beds are red sandstones and interbedding keratophyre passing up into a complex sequence of grey, green and red clastics with shelly facies fossils. Above this are red and green mudstones and siltstones with rare graptolites. In the east these are overlain by coarse sandstones and conglomerates. The conglomerates are probably allochthonous. In the west this coarse facies is developed earlier and laterally interfingers with the shelly facies clastics and overlying mudstones. The sub-Wenlock unconformity reported by McKerrow and Campbell from this region is reinterpreted as an appearance of this interfingering.

Kinematic analysis of mélange fabrics provides critical information concerning tectonic processes and evaluation of the kinematics of ancient relative plate motion. Systematic kinematic analysis of deformed structures within a tectonic mélange exposed along the Zagros Suture Zone elucidates that this zone is an ancient transpressional boundary. The mélange is composed of a greywacke and mudstone matrix surrounding various lenses, blocks and ribbons of radiolarian chert, limestone, sandstone, pillow lava, tuff, serpentinite, shale and marl. The deformation fabrics of the mélange suggest that the mélange units were tectonically accreted at shallow levels within a subduction complex, resulting in layer-parallel extension and shearing along a NW–SE-trending suture that juxtaposes the Afro-Arabian continent to the south and the Central Iranian microcontinents to the north. The tectonic mélange is characterized by subhorizontal layer-parallel extension and subsequent heterogeneous non-coaxial shear resulting in alternating asymmetric and layer-parallel extensional fabrics such as P–Y fabrics and boudinaged layers. Kinematic data suggest that the mélange formed during oblique subduction of the Neo-Tethys oceanic lithosphere in Late Cretaceous time. Kinematic shear sense indicators reveal that the slip direction (N9°E to N14°E) during accretion-related deformations reflects the relative plate motion between the Afro-Arabian continent and Central Iranian microcontinents during Late Cretaceous to Miocene times.

The chitinozoans recovered from six graptolitic horizons in the Buttington Brick Pit, Wales, are described. A correlation between the upper Llandovery and lower Wenlock chitinozoan and graptolite biostratigraphical schemes is presented. These data are compared with the recently refined chitinozoan biostratigraphical scheme in the nearby Banwy River section, Wales. Chitinozoans from definite turriculatus graptolite Biozone strata are described for the first time from the UK. Chitinozoans indicative of the Eisenackitina dolioliformis Biozone occur in the turriculatus Biozone, although the base of the former biozone probably occurs at a lower stratigraphical level. The Angochitina longicollis chitinozoan Biozone has been identified in middle or probably upper spiralis graptolite Biozone strata. Questionably identified A. longicollis occurs lower, in strata assigned to the middle spiralis Biozone, where it occurs with the short-ranging Conochitina mathrafalensis and Belonechitina cavei. This may indicate that: (1) the base of the longicollis Biozone occurs slightly lower in the Telychian in Buttington Brick Pit than in the more basinal Banwy River section; (2) the specimen assigned to A. longicollis? represents an undescribed species; or (3) C. mathrafalensis and B. cavei occur higher in Buttington Brick Pit than in the Banwy River section. The absence of A. longicollis in the turriculatus and crispus graptolite biozones in Buttington highlights the need to re-examine the specimens assigned to A. longicollis from these levels in Estonia, Sweden and Norway. Chitinozoans indicative of the Margachitina margaritana chitinozoan Biozone occur in murchisoni Biozone strata (the base of the former biozone has not been observed at Buttington), and the occurrence of Conochitina flamma indicates that the highest graptolite bed examined correlates with a level high in the murchisoni graptolite Biozone.

The teeth known as Cladodus (type C. mirabilis, Ag.) have a flattened, transversely elongated, sub-elliptical or reniform base, the anterior margin being straighter than the posterior and often slightly excavated in the middle. Anteriorly the base is thick, and generally shows a groove separating the truly basal from the coronal portion, while the posterior margin is thin owing to the downward and backward slope of the ripper surface. From this upper surface anteriorly spring a number of cones or denticles, of which the median is the longest; it is flanked by lateral denticles, of which an outer one on each side is longer than those intermediate. The larger denticles, at least, are flattened antero-posteriorly and have lateral cutting margins.

High-grade basic and acidic meta-igneous rocks are widespread in the bimodal amphibolitic—felsic gneiss complexes, which are characteristic formations of the ‘Middle Allochthonous Unit’ from eastern and southern French Massif Central. The metabasites from the Lyonnais and Doux complexes are chemically diverse and range from N-MORB type tholeiitic to transitional types. The two populations are not related by fractional crystallization or crustal contamination processes and their chemical characteristics reflect differences in their mantle sources. An ensialic setting is supported by the crustally-derived character of some of the associated felsic rocks, but the presence of N-MORB-type metabasites argues for an extensional environment. This bimodal association compares well with the magmatism of rifted continental margins and may reflect a transitional stage between continental rifting and oceanic crust formation during the Cambro-Ordovician spreading event.

Oldowan sites in primary geological context are rare in the archaeological record. Here we describe the depositional environment of Oldowan occurrences at Kanjera South, Kenya, based on field descriptions and granulometric analysis. Excavations have recovered a large Oldowan artefact sample as well as the oldest substantial sample of archaeological fauna. The deposits at Kanjera South consist of 30 m of fluvial, colluvial and lacustrine sediments. Magneto- and biostratigraphy indicate the Kanjera South Member of the Kanjera Formation was deposited during 2.3–1.92 Ma, with 2.0 Ma being a likely age for the archaeological occurrences. Oldowan artefacts and associated fauna were deposited in the colluvial and alluvial silts and sands of beds KS1–3, in the margins of a lake basin. Field descriptions and granulometric analysis of the sediment fine fraction indicate that sediments from within the main archaeological horizon were emplaced as a combination of tractional and hyperconcentrated flows with limited evidence of debris-flow deposition. This style of deposition is unlikely to significantly erode or disturb the underlying surface, and therefore promotes preservation of surface archaeological accumulations. Hominins were repeatedly attracted to the site locale, and rapid sedimentation, minimal bone weathering and an absence of bone or artefact rounding further indicate that fossils and artefacts were quickly buried.

As a result of wide recognition in recent years of extensive overfolding and overthrusting, it seems to have become generally admitted that continents have actually moved horizontally in times of orogeny; but the problem as to how and to what extent such horizontal movements were effected has continued to be an irritating cause for heated disputes and also a fertile ground for wild speculation. In making the present attempt to attack this controversial problem, it is not intended to deal with the merits or demerits of the several species of theories or hypotheses connected therewith, but simply to direct attention to certain groups of geotectonic phenomena found in Eastern Asia and elsewhere, and also to the mechanism responsible for their production as may be attested by experimental means. In this way it is hoped that mere speculation may be eliminated.

Numerous specimens of Lingula tenuissima Bronn have been discovered in the Lower Keuper near Eakring, Notts. Earlier records of fossil bivalves in this formation are recalled and the implications of the present find discussed in relation to conditions of deposition of the Keuper.

Element, carbon and oxygen isotope fractionations have been studied in laminated deposits, manganese nodules and phosphorite lenses in clastic sediments of the Cambrian Timna Formation, southern Israel. Comparisons of element abundances show that only manganese, phosphorus and uranium were mobilized and concentrated during diagenesis: element fractionations among the diagenetic manganese components particularly resemble those observed in present-day suboxic pelagic marine sediments. Epigenetic processes involving reducing solutions reversed the diagenetic geochemical trends, with the redox-sensitive elements manganese and uranium showing considerable depletions in nodules, and iron and lead showing corresponding enrichments. The manganese oxides of nodules have calculated δ18O compositions varying from –1.6 to 3.1 ‰. These compositions are significantly lower than a δ18O value of 7.9 ‰ obtained for the manganese oxides of an ocean floor nodule and are taken to largely represent temperature differences between the ocean floor and the shallow marine Timna conditions. Slight decreases in δ18O accompany the transformation from diagenetic type A to epigenetic type B manganese nodules; corresponding shifts to lower δ18O are also inferred for the structural carbonate of apatites. Such shifts are compatible with re-equilibration accompanying a slight temperature increase and/or low temperature meteoric-water alteration. δ13C values of –7 to –12‰ obtained for the apatites of laminated deposits and phosphorite lenses are consistent with phosphorite diagenesis in suboxic to anoxic pore-waters. Early diagenetic redox conditions are indicated to be major controls governing the development of the assemblages.

Ordovician metamorphic rocks of the Casco Bay Group are exposed in an approximately 170 km long NE-trending belt (Liberty-Orrington belt) in southern and south-central Maine. Geochemical analysis of rocks within the Spring Point Formation (469±3 Ma) of the Casco Bay Group indicate that it is an assemblage of metamorphosed bimodal volcanic rocks. The mafic rocks (originally basalts) have trace element and Nd isotopic characteristics consistent with derivation from a mantle source enriched by a crustal and/or subduction component. The felsic rocks (originally rhyolites and dacites) were likely generated through partial melting of continental crust in response to intrusion of the mafic magma. Relatively low initial εNd values for both the mafic (−1.3 to +0.6) and felsic (−4.1 to −3.8) rocks suggest interactions with Gander zone continental crust and support a correlation between the Casco Bay Group and the Bathurst Supergroup in the Miramichi belt of New Brunswick. This correlation suggests that elements of the Early to Middle Ordovician Tetagouche-Exploits back-arc basin can be traced well into southern Maine. A possible tectonic model for the evolution of the Casco Bay Group involves the initiation of arc volcanism in Early Ordovician time along the Gander continental margin on the eastern side of the Iapetus Ocean basin. Slab rollback and trenchward migration of arc magmatism initiated crustal thinning and rifting of the volcanic arc around 470 Ma and resulted in the eruption of the Spring Point volcanic rocks in a back-arc tectonic setting.

Stratigraphic sections measured at Wilhelmøya and Hellwaldfjellet in eastern Svalbard are described in their entirety in terms of formal lithostratigraphic units for the first time. They include rocks of mid-Triassic to late Jurassic age. The Uleneset Member is newly described and palynological evidence is used to show that it is largely Norian (late Triassic) in age.

When looking through the bibliography referring to the crypto– volcanic phenomena of Swabia we find that it has been quite customary to explain the origin of the “Steinheim Basin” by the well–known facts which have been ascertained in the Ries of Nördlingen. When doing so one important fact has been deliberately ignored, viz, that only the Steinheim basin is actually cryptovolcanic, whereas the Ries of Nördlingen exhibits undeniable proofs of extensive volcanic activity. There are rhyolitic tuffs, weathered– out lava cords and lava slabs, partly absorbed crystalline rocks, et alia. In the case of the Ries of Nördlingen the explanation of the vast caldera and the various geologic abnormalities must obviously be sought in volcanic activity.

The purpose of this paper is to place on record some interesting occurrences of crinoids in the Scottish and Irish Carboniferous Limestones. Some of the descriptions of new species are preliminary to a fuller study of the subject.

A collection of conodonts, including Dapsilodus obliquicostatus (Branson & Mehl), Distomodus cf. kentuckyensis Branson & Branson, Ozarkodina oldhamensis (Rexroad), and Panderodus sp., has been obtained from brachiopod coquinas in the lower part of the La Chilca Formation in the Precordillera of west-central Argentina. This conodont fauna, the first to be recorded from the Llandovery in South America, can be referred to the D. kentuckyensis Biozone, and is interpreted to represent an interval in the middle Rhuddanian to lower Aeronian stages. This age assignment is supported by graptolite data from the lower third of the La Chilca Formation beneath the conodont-bearing interval. The brachiopods associated with the conodonts belong to the Afro-South American Realm, but include a high percentage of North Atlantic and cosmopolitan genera. The conodont taxa present are widespread in the tropical zone (Laurentia, Baltica, etc.). This suggests that the pronounced conodont faunal provicialism in the Upper Ordovician had disappeared in the Lower Silurian, where high- and low-latitude conodont faunas appear to be closely similar.

The Rev. Richard Baron, F.G.S., of the London Missionary Society, has sent to the British Museum some interesting reptilian remains from the Jurassic rocks of Madagascar, which he obtained during 1891, at Andranosamonta village, a locality situated in the north-western part of the Island. They were enclosed in a tenacious slielly limestone, so that before their examination could be proceeded with it was necessary to submit them to careful development and cleaning, a work whioh has been most ably carried out by Mr. Richard Hall, the Assistant Formatore of the Geological Department.

A new genus and new species of primitive eucryptodiran turtle, Phunoichelys thirakhupti gen. et sp. nov., is described on the basis of shell remains from the lower part of the Phu Kradung Formation, at Phu Noi locality, Kalasin Province, NE Thailand. It is assigned to Xinjiangchelyidae on the basis of the marginals covering the lateral end of the costals and the anal scutes invading the hypoplastra. The new taxon is further characterized by a low and rounded carapace without a cervical notch; the whole carapace and plastron covered with a clear ornamentation consisting of tiny irregular vermiculated furrows; a complete neural series that reaches the suprapygal; a very wide and short cervical scute; relatively wide vertebral scutes; and a long first thoracic rib that extends along the full width of the first costal. The sutured plastron/carapace connection and the marginals covering the lateral end of the second to seventh costals suggest that the turtles from Phu Noi may be related to some primitive xinjiangchelyids from the Sichuan Basin. The discovery of a xinjiangchelyid turtle in the lower part of the Phu Kradung Formation supports a Late Jurassic age for that part of the formation.