Mineralogical studies of a silicified serpentinite from the United Arab Emirates throw light on the formative processes. The silicified serpentinite is a residuum of a palaeo-weathering surface that probably developed in a temperate climate with alternating wet and dry periods during middle Eocene to late Miocene times. The rock textures indicate that silicification occurred in a fluid-saturated zone. Silica precipitation is favoured at near-neutral pH. In this study we infer that these pH conditions of the mineralizing fluids could arise in a near-surface mixing zone where acidic meteoric and hyperalkaline groundwater fluids are mingled. This mingling is believed to have resulted from alternating processes of evaporation and precipitation that prevailed during dry and wet seasons, respectively. The silicified serpentinite is composed of > 95% quartz and exhibits a ghost texture of the protolith serpentinite. Preservation of the textures indicates an iso-volumetric grain-by-grain replacement by dissolution of Mg-silicate and simultaneous precipitation of either opal or microquartz as siliceous seeds. These were subsequently overgrown by silica that was probably remobilized from deeply weathered regolith elsewhere.

The boundary between the Rhoscolyn and New Harbour formations on Holy Island, Anglesey, has been described as a high strain zone or as a thrust. The boundary is here described at four localities, with reference to the contrasting sedimentary and deformational character of the two formations. At one of these localities, Borth Wen, sandstones and conglomerates at the top of the Rhoscolyn Formation are followed, without any break, by tuffs and then mudstones of the New Harbour Formation. It is concluded that there is clear evidence of depositional continuity across the boundary here, and that both formations subsequently shared a common two-phase deformation. The first (D1) was manifestly different in intensity and scale in the two formations, whereas the second (D2) produced very similar structures in both. The other three localities provide continuity of sedimentary and tectonic features at this boundary in a traverse along the length of Holy Island, leading us to identify two previously unrecognized major D1 folds in addition to the Rhoscolyn Anticline. At one of these localities (Holyhead), we confirm the presence of Skolithos just below the boundary, supporting radiometric evidence for a lower Cambrian or later age for the Rhoscolyn Formation. A turbidite interpretation for both the Rhoscolyn and New Harbour formations best fits the available evidence. A deep-water depositional environment is still compatible with the sporadic presence of Skolithos burrows, but less so with reported observations of hummocky and swaley cross-stratification lower down the South Stack Group.

Early–Middle Miocene intraplate basalts from the Aleppo Plateau, NW Syria have been analysed for their platinum-group elements (PGEs). They contain extremely low PGE abundances, comparable with most alkali basalts, such as those from Hawaii, and mid-ocean ridge basalts. The low abundances, together with high Pd/Ir, Pt/Ir, Ni/Ir, Cu/Pd, Y/Pt and Cu/Zr are consistent with sulphide fractionation, which likely occurred during partial melting and melt extraction within the mantle. Some of the basalts are too depleted in PGEs to be explained solely by partial melting of a primitive mantle-like source. Such ultra-low PGE abundances, however, are possible if the source contains some mafic lithologies. Many of the basalts also exhibit suprachondritic Pd/Pt ratios of up to an order of magnitude higher than primitive mantle and chondrite, an increase too high to be attributable to fractionation of spinel and silicate minerals alone. The elevated Pd/Pt, associated with a decrease in Pt but not Ir and Ru, are also inconsistent with removal of Pt-bearing PGE minerals or alloys, which should have concurrently lowered Pt, Ir and Ru. In contrast, melting of a metasomatized source comprising sulphides whose Pt and to a lesser extent Rh were selectively mobilized through interaction with silicate melts, may provide an explanation.

Late Ordovician fossils, including the distinctive Hirnantia brachiopod Fauna, have been found in Lower Palaeozoic successions in Istanbul and Bolu (Yığılca), western Pontides, NW Turkey. The Middle Ordovician (Sandbian) faunas belong to the cooler-water Mediterranean Province, and they are followed by Katian brachiopods including Sulevorthis, Nicolella, Hesperorthis, Glyptorthis, Saukrodictya and Kullervo and ostracods such as Piretella, Eochilina and Klimphores, which represent deposition in warmer waters; however, the Mediterranean Province usually cooler-water brachiopods Drabovia and Leptestiina also occur. The Pendik Formation includes thin bryozoan-rich limestones which probably represent the Boda Global Warming Event. The overlying turbidites contain a Hirnantia Fauna, developed within a brachiopod–diplograptid association. Above them there are characteristic Llandovery (Rhuddanian–Aeronian) brachiopods, such as Leangella, Eoplectodonta, Stricklandia and Hindella with the corals Halysites, Paleofavosites and Streptelasma. In the Bolu area, Katian brachiopods such as Mcewanella, Dalmanella, Glyptorthis, Christiania, Oligorhynchia, Nicolella, Howellites and Drabovinella also occur, but there the overlying Hirnantia Fauna is developed within a Hirnantia–Mucronaspis association. The fauna and sediments indicate that the western Pontides were not very cold during the latest Ordovician. Despite Turkey being placed in higher latitudes by previous authors, it seems more probable that the Pontides were at somewhat lower palaeolatitudes, perhaps at about 40°S in those times; however, the precise palaeogeographical position of the terrane remains uncertain: there are no Hirnantian glaciogenic rocks there, such as are found in the Taurides of southern Turkey.

An isolated, fully articulated hindlimb of a basal iguanodont from the Spanish Las Hoyas Lagerstätte is described. It probably belonged to a juvenile or subadult individual. Despite some slight differences, anatomical features, as well as the late Barremian age of this specimen, would suggest that it belongs to Mantellisaurus atherfieldensis. The exquisite preservation of this specimen provides information on the foot anatomy of basal iguanodonts. This is the first report of a non-theropod dinosaur from Las Hoyas. From a palaeoecological point of view, this discovery indicates that potential prey of the carcharodontosaurian theropod Concavenator were present at Las Hoyas, thus complementing our knowledge of the trophic structure of this Early Cretaceous palaeocommunity.

Tectonic and thermal perturbations, related to emplacement of granodiorite in the upper continental crust, have been investigated in the late-Hercynian basement exposed in southern Calabria (Italy). Here, the structural aureole is marked by the presence of a major rim fold adjacent to the intrusive contact for a length of at least 20 km. Geometrical analysis of the structural aureole and related foliations, lineations and crenulations reveals that the perturbed zone is at least 3000 m wide and characterized by an open synform trending nearly parallel to the intrusive contact. This pattern is compatible with a laccolith-like mode of magma emplacement, related to the accretion of the pluton that shouldered weak phyllitic and slaty wall rocks. The metamorphic aureole, about 1800 m wide, is characterized by biotite, cordierite and andalusite that appear sequentially in spotted schists and hornfelses approaching the intrusive contact. The peak assemblage equilibrated between 535 and 590°C at pressures between 175 and 200 MPa, confirmed by Al-in-hornblende barometry on granodiorite. Microstructural analysis allowed the inference of a time lag between the thermal and tectonic perturbations. With the aid of thermal modelling it was possible to quantify the time required to reach the peak temperature at a distance from the intrusive contact where cordierite spots and andalusite porphyroblasts clearly overprint crenulations. This estimate represents the time limit to accomplish deformation in the inner portion of the aureole and thus indicates a minimum strain rate of 4 × 10−14 s−1 within the country rocks during granodiorite intrusion.

The city of Naples can be considered part of the Campi Flegrei volcanic field, and deposits within the urban area record many autochthonous pre- to post-caldera eruptions. Age measurements were carried out using 40Ar–39Ar dating techniques on samples from small monogenetic vents and more widely distributed tephra layers. The 40Ar–39Ar ages on feldspar phenocrysts yielded ages of c. 16 ka and 22 ka for events older than the Neapolitan Yellow Tuff caldera-forming eruption (15 ka), and ages of c. 40 ka, 53 ka and 78 ka for events older than the Campanian Ignimbrite caldera-forming eruption (39 ka). The oldest age obtained is 18 ka older than previous dates for pyroclastic deposits cropping out along the northern rim of Campi Flegrei. The results of this study allow us to divide the Campi Flegrei volcanic history into four main, geochronologically distinct eruptive cycles. A new period, the Paleoflegrei, occurred before 74–78 ka and has been proposed to better discriminate the ancient volcanism in the volcanic field. The eruptive history of Campi Flegrei extends possibly further back than this, but the products of previous eruptions are difficult to date owing to the lack of fresh juvenile clasts. These new geochronological data, together with recently published ages related to young volcanic edifices located in the city of Naples (Nisida volcano, 3.9 ka) testify to persistent activity over a period of at least 80 ka, with an average eruption recurrence interval of ~555 years within and adjacent to this densely populated city.

Several enigmatic sedimentary structures are present in Upper Silurian and Lower Devonian terrestrial rocks of south Wales. These are millimetre ripples, wrinkle structures, ‘cauliflower’ and ‘molehill’ structures, calcretized matgrounds, ‘pepper-pots’ and ‘fairy rings’. Most of the structures occur on fine-grained sandstone bedding surfaces in both inclined and non-inclined red heterolithic deposits that form a large part of the Lower Old Red Sandstone in south Wales. These deposits consist of conspicuous units up to 3 m thick, comprising millimetre- to centimetre-scale laminasets of alternating mudstone and fine-grained sandstone, interpreted as muddy point bars on ephemeral channel margins, crevasse-splay lobes or distal flood-out deposits from ephemeral flow. They are rich in trace fossils reflecting animal locomotion, burrowing, foraging, ploughing and resting. Millimetre ripples and wrinkle structures are related to rapid growth of cyanobacterial mats on wet sediment surfaces, especially in films of standing water, that may have been a critical constituent of the food chain for terrestrial communities. Pustular ‘cauliflower’ and ‘molehill’ structures are preserved on tuffs and have been linked to algal blooms formed following an increase in nutrients due to ashfall into floodplain ponds. The tuffs are associated with a diverse ichnofauna indicating that opportunist colonizers took advantage of an abundant food source.

The Gardar Rift in southern Greenland developed within Palaeoproterozoic rocks of the Ketilidian orogen, near its boundary with the Archaean craton. The Eriksfjord Formation was deposited at c. 1.3 Ga on a basement of c. 1.8 Ga Julianehåb I-type granite. Detrital zircons from the lower sandstone units shows a range of ages and εHf compatible with proto sources within the Archaean craton and the Nagssugtoquidian mobile belt north and east of the craton; zircons that can be attributed to juvenile Ketilidian sources are less abundant. This suggests a predominance of distant sources, probably by recycling of older and no longer preserved cover strata. A significant fraction of c. 1300 Ma zircons have εHf between 0 and −38. Rather than originating from a hitherto unknown igneous body within the Gardar Rift, these are interpreted as Palaeoproterozoic to late Archaean zircons that have lost radiogenic lead during diagenesis and post-depositional thermal alteration related to Gardar magmatism. Although the sediments originate from sources within Greenland, the age and initial Hf isotope distribution of Palaeoproterozoic and Archaean zircons mimics that of granitoids from the Fennoscandian Shield. This may reflect parallel evolution and possible long-range exchange of detritus in Proterozoic supercontinent settings. The lesson to be learned is that detrital zircon age data should not be used to constrain the age of sedimentary deposition unless the post-depositional history is well understood, and that recycling of old sediments, long-range transport and parallel evolution of different continents make detrital zircons unreliable indicators of provenance.

A new sea spider (Arthropoda: Pycnogonida) from the Lower Devonian Hunsrück Slate (Germany) is described as Pentapantopus vogteli gen. et sp. nov. This is the fifth pycnogonid species known from this exceptional fossil Lagerstätte. The most conspicuous character of the new species is the presence of five pairs of walking legs. This character, in concert with a reduced abdomen, indicates a phylogenetic position of P. vogteli among the crown group pycnogonids. P. vogteli extends the knowledge of fossil pycnogonid body plans and underlines the significance of the Hunsrück Slate, as this locality shows the highest diversity of sea spiders for the entire fossil record so far.

Aglaspidids represent an obscure group of lower Palaeozoic arthropods with a patchy biogeographic distribution. Before the recent description of a representative from Tasmania, these arthropods were exclusively known from Laurentia during the late Cambrian. Here we describe a new species, Aglaspella sanduensis sp. nov., from the Furongian of China, confirming that aglaspidids sensu stricto were already widely distributed worldwide by the late Cambrian; this demonstrates that some aglaspidids had great dispersal capabilities. A new diagnosis of the genus Aglaspella is proposed and the species formerly known as Aglaspella eatoni is assigned to a new taxon, Hesselbonia gen. nov.

Detrital zircon U-Pb ages for 30 Late Jurassic and Cretaceous sandstones from the Eastern Province of eastern New Zealand, combined with previously-published geochronological and palaeontological data, constrain the time of deposition in the Pahau and Waioeka terranes of the Cretaceous accretionary margin of Zealandia, and their adjacent cover strata. The zircon age patterns also constrain possible sediment source areas and mid-Cretaceous geodynamic models of the transition from basement accretionary wedge to passive-margin cover successions. Pahau Terrane deposition was mainly Barremian to Aptian but continued locally through to late Albian time, with major source areas in the adjacent Kaweka and Waipapa terranes and minor inputs from the inboard Median Batholith. Waioeka Terrane deposition was mainly Albian, with distinctive and exclusive sediment sources, principally from the Median Batholith but with minor inputs from the Western Province. Alternative tectonic models to deliver such exclusive Median Batholith and Western Province-derived sediment to the mid-Cretaceous Zealandia continental margin are: (1) the creation of a rift depression across Zealandia or (2) sinistral displacement of South Zealandia with respect to North Zealandia, to expose Western Province rocks directly at the Zealandia margin. Detrital zircon age patterns of Cretaceous cover successions of the Eastern Province of eastern New Zealand demonstrate purely local sources in the adjacent Kaweka and Waipapa terranes. Cretaceous zircon components show a decline in successions of late Early Cretaceous age and disappear by late Late Cretaceous time, suggesting the abandonment or loss of access to both the Median Batholith and Western Province as sediment sources.

The first ever list of the regional Öland Series (Tremadocian to mid Darriwilian) trilobites and agnostids from the whole of Baltoscandia is compiled. The study includes revision of systematics as well as vertical and horizontal distribution. This is necessary because of the uneven state of knowledge, some faunas having being studied recently, others not for more than a century. Three successive faunal types are recognized: the Olenid Fauna surviving from the Cambrian in black bituminous shale facies, the immigrating Ceratopyge Fauna, and the stabilized Asaphid Fauna. The latter fauna collapsed in the middle of Darriwilian and gave way to a set of new post-Ölandian faunas.

Magmas in Faial Island, Azores (Portugal), were mostly erupted from two fissure zones and the Caldeira central volcano during overlapping periods. The fissure zones follow extensional trends oriented WNW and ESE and erupted nepheline- to hypersthene-normative basalts and hawaiites. The Caldeira central volcano builds the central part of the island, which is cut by the fissure zones. Ne-normative basalts show similar high-field-strength element (HFSE) concentrations but higher large ion lithophile element (LILE) concentrations than hy-normative equivalents. Primitive melts were generated by small (3–5%) degrees of partial melting of garnet-bearing peridotite, variably enriched in incompatible elements. Overall, basalts from Faial show relatively higher LILE abundances and LILE/HFSE ratios than those of the other islands of the Azores and of many other volcanoes in the Atlantic area. This feature indicates the existence of chemical heterogeneities in the mantle sources characterized by variable degrees of metasomatism, both at local and regional scales. Hawaiites evolved from basalts through 30–40% fractional crystallization of mafic phases plus some plagioclase, in deep reservoirs, at about 430–425 MPa (~ 15 km). The Caldeira central volcano rocks range from basalts to trachytes. Basalts, produced under similar conditions as fissure basalts, evolved to trachytes through large degrees of polybaric fractional crystallization (100–760 MPa; i.e. ~ 3.6–26 km), involving olivine, clinopyroxene, feldspar and minor quantities of amphibole, biotite, apatite and oxides. In contrast, mafic magmas from the fissure zones were erupted directly onto the surface from magma reservoirs mainly located at the crust–mantle boundary.