The six exposures of the Upper tectonic Unit of the Cycladic Massif occurring on the island of Tinos are shown to comprise a metamorphosed dismembered ophiolite complex. The common stratigraphic section consisting of tens-of-metres- thick tectonic slices of mafic phyllites overlain by serpentinites and gabbros is considered to have been derived by a combination of thrusting during obduction and subsequent attenuation by low-angle normal faults. All rock types show evidence of a phase of regional greenschist-facies metamorphism, which in the case of the phyllites is accompanied by penetrative deformation. The greenschist-facies metamorphism in gabbros is preceded by high temperature sea-floor amphibolite-facies alteration, whereas in the serpentinites, the antigorite + forsterite greenschist-facies assemblage overprinted an earlier low temperature lizardite serpentinite. Trace element patterns of the mafic phyllites and a harzburgitic origin of meta-serpentinites suggest a supra subduction zone (SSZ) affinity for the ophiolitic suite. ρ18O values of phyllites, gabbros and serpentinites range from 6 to 15%o. Model calculations indicate that such values are consistent with low temperature (50–200°C) alteration of parent rocks by sea-water at varying water/rock ratios. This would agree with the early low temperature mineralogy of the serpentinites, but the early high temperature alteration of the gabbros would require the presence of 18O-enriched sea-water.The following overall history is suggested for Tinos ophiolitic slices. (1) Oceanic crust was generated at a supra-subduction zone spreading centre with high temperature alteration of gabbros. (2) Tectonic disturbance (its early hot stages recorded in an amphibolitic shear zone at the base of serpentinites) brought the already cooled ultramafics into direct contact with sea-water and caused low-T serpentinization. (3) Tectonism after cooling involved thrusting which caused repetition and inversion of the original order of the oceanic suite. (4) Regional metamorphism of all the ophiolite components at greenschist-facies conditions (−450°C) overprinted the early alteration mineralogy. It was probably induced by continued thrusting and piling up of nappes. The Tinos ophiolite, dated as late Cretaceous and genetically related to other low pressure rock-units of the same age in the Aegean, differs in age and degree of dismemberment and metamorphism from ophiolites in mainland Greece.

The deposits of the Pliocene—Quaternary foredeep of the Northern Apennine cover at present an area of 103000 km2. The original boundaries of the basin are not known, since marginal deposits have been eroded, in particular those of the inner, southwestern border. During Pliocene times the basin area was reduced by thrust tectonics and the amount of shortening may be tentatively estimated.

The present volume of Pliocene and Quaternary sediments may be inferred with good approximation from the maps of the base of the Pliocene and of the Quaternary (base of the Hyalinea balthica Zone) successions. The Pliocene volume has been corrected adding the estimate of the underthrust sediments, while no correction has been attempted for the eroded marginal deposits. The estimates of 97000 and 95000km3. reflecting the present volume of the Pliocene and Quaternary deposits, are therefore significantly less than the volumes originally deposited.

Present volumes have been transformed in ‘net’ (0% porosity) volumes, in order to obtain the relative net supply rates: 0.021 (Pliocene) and 0.047 (Quaternary) km3/a. Other unmeasurable factors (volume variations due to the weathering of silicates, loss of leached carbonates) may induce a probably unimportant underestimate of the supply rates.

Available data allow an approximate estimate of the range of the net volume of the Holocene sediments deposited during the last 6000 a BP (221–276km3) and of the relative net supply rate (0.037–0.046km3/a), that is not significantly different from the Quaternary one. Applying a porosity correction, these supply rates may be related to the Quaternary source area (128000km2) to obtain the relative denudation rates: 0.41–0.46mm/a (Quaternary) and 0.36–0.51 mm/a (Holocene). Present supply and denudation rates, deduced from the direct measurements of the bed load and suspended load of the apenninic and alpine rivers, do not differ significantly from the Quaternary and Holocene ones.

Available data do not allow a reliable estimate of the Pliocene source area, and consequently of the Pliocene denudation rate. However, a minimum of 160000–177 000 km3 has been eroded during Pliocene and Quaternary times. Assuming, as a working hypothesis, that the Pliocene source area did not significantly differ from the present one, an average thickness of 1240–1390 m could have been eroded since the beginning of Pliocene. This estimate is in agreement with the values obtained from the measurements of coalification of vegetal organic matter in the outcrops, and suggests that post-orogenic successions and ‘higher’ thrust sheets may have been completely removed in vast areas.

The Kula province of Western Turkey provides an excellent example of an alkali basalt province in an area of active rifting. This paper establishes the relationship between the generation of the basalts and the extension of the region. The wide, shallow, terrestrial basin, formed by early extension, was subsequently cut through by narrow, fault-bounded grabens. The genesis of alkali basalt magmas began soon after the concentration of the extension into two grabens ˜2 Ma. The basalts, in the form of some 80 small cinder cones and associated lava flows and fields, have a total volume of 2.3 km3. This small volume reflects the small amount of extension in the region (β < 1.2 where β = final length of crust: initial length of crust).The intercalation of sediments and basalts in the Kula area enables the establishment of a relationship between the extensional activity and the generation of the basalts. This is demonstrable using radiometric and stratigraphic techniques, notably Ar-Ar dating of amphibole phenocrysts.

Latest Devonian A-type granite-gabbro plutons, in part ductilely deformed, are spatially associated with the strike-slip Cobequid fault zone. The youngest intrusions are close to the Cobequid fault zone, which was the main conduit for magma. Two phases of deformation accompanying magma emplacement are recognized. Early magmas intruded ductile rocks during left-lateral oblique thrust movements. A second stage of right-lateral oblique slip normal faulting accommodated uplift of the plutons when coarse granite was emplaced in the crestal regions. Cross-cutting late stage porphyries, granitic clasts in marginal basins cut by granitic dykes, and superposition of brittle on ductile structures all indicate rapid uplift of the plutons. The geometry of the Cobequid fault zone shows that pluton emplacement was not the result of extension in releasing bends during transcurrent shear. Rather, flower-structure high-angle faults acted as magma conduits and space was created by two processes: translation of wall rocks along thrust faults at depth, developing space away from the master fault zone and backward collapse of the uplifted magma chamber creating space towards the fault zone.

The specimen is identified as the partial cranium of a nodosaurid ankylosaur (Ornithischia: Thyreophora) on the basis of the presence of bone which is fused to the dorsal surface of the skull and has secondarily closed the upper temporal fenestrae. The only unequivocally nodosaurid material recovered from the Isle of Wight to date comes from Wealden facies, and has been referred to the genus Polacanthus; it is considered highly probable that this new skull is referable to the same genus. Despite having undergone abrasion, through post-emergence water-rolling, the skull and cranial walls have proved to be relatively informative of the general anatomy of the braincase and the neural and vascular anatomy of this part of the head. The anatomy of the braincase of most ankylosaurs (with the notable exception of the juvenile specimens of the ankylosaurid Pinacosaurus) is surprisingly poorly known, despite the relative abundance of cranial material in North American and Asian collections.

The cranial neural and vascular anatomy is well shown in this specimen and enables the first detailed description of nodosaurid endocranial structures. The general form of the brain can be outlined from the structure of the endocast and the principal lobes can be identified; the majority of the cranial nerves have been identified, and a significant component of the associated vascular system is also visible. In most respects the endocast shows a neural anatomy which is common to that known in most dinosaurs. When compared to their nearest relatives, the ankylosaurid ankylosaurs (Euoplocephalus), the nodosaurid endocranial cast shows a more pronounced cerebral flexure, a forebrain which is broader and more expanded dorsally, and a more prominent cerebellum (although there is no evidence for a floccular lobe); there are minor differences in the arrangement of the cranial nerves, and the dorsal portions of the vascular system are better shown.

Because of erosion, the olfactory lobes of this specimen of cf. Polacanthus are not preserved, and cannot be compared to those of ankylosaurid ankylosaurs; the latter are unusual in the strong separation of the lobes (reflected in the divergent olfactory stalks); this feature may be associated with the very complex passages within the nasal region of the skull, which are lacking in the nodosaurids described to date.

We report U—Pb and 207Pb/206Pb zircon ages for a granulite facies gneiss assemblage exposed in a large quarry at Ihosy, southern Madagascar. The granulites are derived from pelitic to arkosic sediments and attained equilibrium conditions at 650–700°C and 4–5 kbar. Higher P—T conditions of 750–800°C and 6 kbar in the presence of low water activities have led to dehydration melting processes. The formation of granitic melts, which (partly) moved away from their source region, intruded into upper parts of the metapelitic gneisses as small granitic veins and left behind granulitic garnet-cordierite-quartz bearing rocks. Detrital zircons in a sample of metapelite and a sample of quartzofeldspathic gneiss yielded ages between ˜720 and ˜1855 Ma, suggesting a chronologically heterogeneous source region and a depositional age of less than ˜720 Ma for these rocks. High-grade metamorphism and anatexis are documented by zircon ages between 526 ±34 and 557 ±2 Ma with a mean age of about 550 Ma. The broad lithologies, metamorphic grades and ages recorded in the Ihosy rocks are similar to those in the Wanni Complex of northwestern Sri Lanka and in high-grade assemblages of southernmost India and support the contention that all these terrains were part of the Mozambique belt which formed as a result of collision of East and West Gondwana in latest Precambrian time.

A significant 5- to 30-metre-thick interval of siliciclastic turbidites forming the First Flysch is present in the deep-water succession of the Pindos Zone. Nannofossil investigations in the central parts of the Pindos Mountains of mainland Greece indicate an assemblage of the Marthasterites furcatus zone (CC13). The presence of M. furcatus, together with common Quadrum gartneri suggests that the turbidites were deposited mainly during the middle to upper part of the late Turonian. The siliciclastic turbidites are interpreted as deposits of a lowstand fan as a result of a pronounced short-time eustatic sea-level drop in the late Turonian.

Single grain 207Pb/206Pb zircon ages were determined for granitoids and gneisses which constitute the Archaean basement rocks of the Aravalli craton of Rajasthan, northwestern Indian Shield. The protolith ages for two gneisses, collected from east of Udaipur, are ˜3230 Ma and 2887 Ma respectively. The granitoids display an intrusive relationship with the gneisses and yielded ages ranging between 2666 Ma and 2620 Ma. These ages provide the basis for a geochronological model of evolution of the oldest basement of the Aravalli craton.

Lack of understanding of the graptolite nema and virgula is probably the main cause of the general failure to arrive at a general mode of life theory for planktonic species. The nema and virgula are shown to be different structures. The nema may have had a rhabdosome rotational function at early growth stages; the primary function of the virgula may have been rhabdosomal rotation, whilst a secondary function was as a stipe growth guide. Rotational function would be inapplicable for pseudovirgulae and in synrhabdosomes.