The regional strike of the bedding and foliation is NW but most of the folds and lineations plunge roughly SW. Lineations that resemble grain (longrain) seem to be usually parallel to the steeply plunging fold axes. This structural pattern occupies more than 2,000 km2. The formation of this pattern of folds was preceded and succeeded by regional folding along horizontal axes.

Recent collections of graptolites from the Călărasi, Ianca-Berlescu and Tăndărei boreholes have helped to refine the stratigraphy of Silurian (Wenlock, Ludlow) and Devonian rocks of the Moesian Platform. Fourteen species are recorded for the first time from Rumanian strata, others are left under open nomenclature, whilst well-preserved specimens of the following species provide additional information on their detailed morphology and hence upon their relationships and evolution: Monocliniacis sp., Holoreriolites (Balticograptus) cf. balticus Eisenack, Saetograptus cf. rams (Teller), Monograptus kolihai Bouček, ?Cyrtograptus sp., Barrandeograpus pulchellus (Tullberg), and ?Neodiversograptus ex gr. nilssoni(Barrande).

A general model for pedogenic carbonate development in alluvial sediments is based upon of rates flood sediment accretion versus time taken for particular carbonate profiles to develop. Conclusions regarding rates of Holocene carbonate pedogenesis and the changing morphology and thicknesses of carbonate profiles with time are used to predict critical values of floodbasin accretion rates which would have enabled particular ancient profiles to develop. Local (intra-drainage basin) and regional profiles are separated and a number of models for calcrete genesis are outlined. The presence or absence of particular genetic stages of calcrete may be used as a rough guide to estimate ancient floodbasin accretion rates.

The geology of Barbuda, a low-lying island in the Lesser Antilles, is reexamined and the stratigraphy is revised. The oldest rocks are limestones of the Highlands Formation, a Middle Miocene accumulation of fore-reef facies. This is overlain successively by the Pleistocene Beazer and Codrington Formations, limestone accumulations of reefal, lagoonal and dune facies. The Holocene Palmetto Point Formation is comprised of extensive beach ridge and dune limestones. From this, the Barbuda Bank (which includes Antigua) is considered to have had a geological history like the neighbouring Anguilla and Guadeloupe Banks.

The nature and timing of ‘spilitization’, and the original composition of ‘spilitized’ Precambrian lavas fron the Athapuscow aulacogen, Great Slave Lake (Canada) are investigated, using geochemical and Rb/Sr isotopic methods. Relationships and abundances of trace elements of petrogenetic significance suggest that the spilites were not derived from alkaline basaltic magmas, but show petrogenetic affinity with tholeiitic basalts from continental or volcanic island environments. This new interpretation conforms well with the supposed tectonic and geologic environment in which the lavas and pyroclastics were erupted. Assuming an ‘open system’ behaviour for Rb and Sr during intense metasomatism, the isochron age of 1872 Ma obtained for the lavas is considered as the time of ‘spilitization’. This age, when compared with geochrono metric data obtained by other techniques, suggests that the time interval between initial volcanism and subsequent ‘spilitization’ event was brief, and probably related to diagenesis or burial metamorphism during rapid subsidence and sedimentation commonly associated with rifting within aulocogens. A relatively low initial 87Sr/86Sr ratio of 0.7018±0.0005 obtained for the lavas either reflects the low Sr isotope values characteristic of diagenetic pore fluid in Precambrian seas, or suggests that the original ‘primitive’ initial ratio was not adversely affected by the ‘spilitization’ process. .

The sedimentology of a key locality in the Caradoc of SW Wales is discussed for the first time. Five facies are described and interpreted: mudstones and siltstones (A), turbidite arenites (B), rudites (C), a diamictite of massflow origin (D), and muddy arenites rich in shaleclasts (E) which show a transition from massflow deposits to immature turbidites. Closely adjacent sections illustrate considerable lateral variations within an assemblage suggested to be of proximal turbidite character and to represent deposits high on a Middle Fan environment.

It is pointed out that some chemically analysed sedimentary rock series when plotted on AFM diagrams (A = Na2O + K2O; F = total iron as FeO; M = MgO) partly mimic trends generally considered characteristic of igneous variation, especially the calc-alkali trend. Although the scatter in sedimentary rock plots is generally greater than that given by igneous rocks this is not necessarily so for calc-alkali suites often show considerable scatter. These observations should be considered when deducing the origin of highly metamorphosed gneisses and quartzo-feldspathic rocks that might be meta-arkoses, meta-granites or meta-volcanic rocks.

An underwater study of recent submarine lava flows on São Miguel (Azores) suggests that the island has subsided by as much as 9 m relative to sea level over the last few thousand years. A spectacular system of overlapping lava arch structures occur immediately below the ancient sea level, and they are thought to have formed when tongues of molten lava flowed over a steep autochthonous submarine scree slope. The scree was subsequently removed by strong longshore currents and wave action.