The drift succession in east-central Ireland is the result of a series of ice movements spreading from major centres of dispersion within theIrish Sea Basin and over the north-central Irish plain, and from local mountain sources. These glaciations have produced laterally and vertically complex sequences of deposits. The large-scale events influenced almost the entire area; problems of correlation emerge when considering episodes of relatively restricted extent such as those associated with upland ice-caps in the S and the hitherto unreported readvances which interrupted the withdrawalof ice-sheets across the northern part of the region under examination. Thetask of assigning the older units to particular Quaternary cold stages is frustrated by the absence of interstratified organic horizons. Two possible models of glaciation are considered: one may be regarded as ‘traditional’; the other requires a much shorter period of time by assuming that the stratigraphy records differences in the relative strengths of essentially contemporaneous ice-masses.

Masirah Island lies off the SE coast of Oman and comprises a fully developed, though tectonically disturbed ophiolite, unconformably overlain by early Tertiary limestone. The ophiolite consists of harzburgites, cumulate gabbros, a sheeted dyke complex, and pillow lavas with sediment intercalations. Within the ophiolite occur granites the geochemistry of which, particularly their high K2O and Rb, and low Zr and Zr/Nb, ismore typical of a continental crust environment and suggests that at the time of their formation continental crust existed beneath or immediately W ofthe Masirah Ophiolite.

As in Kashmir and Arunachal Pradesh (NEFA) Himalayas, the Upper Palaeozoic (Lower Gondwana) sequence in Sikkim Himalayas contains basic lavas. These are interbedded with boulder bed/pebble slate, sandstone andshale, exposed in a tectonic window. Geochemically the basic lavas are characterized by high contents of TiO2, K2O, P2O5 and ‘incompatible’ trace elements. The chemistryis compatible with a small degree of partial melting under high pressure ofa titan-phlogopite-bearing peridotite mantle. The only primary quench phases are frequent apatite, magnetite and profuse ilmenite, the latter accounting for the high FeO/Fe2O3 ratio of the rock, and demonstrating rapid crystallization. The geochemistry of the lavas appears to be consistent with basic volcanism associated with the initiation of continental rifting. From this study and from a consideration of the geochemistry of the volcanic rocks of similar age in Kashmir area, it is suggested that rifting of the northern continental margin of the Indian plate and formation of a transitional crust during Upper Palaeozoic times are important geotectonic features in the Himalayan region.

The palaeoecologic significance of post-Palaeozoic green calcareous algae is evaluated with what is known of the environments of comparable living algae. Here requirements and tolerances of temperature, bottomsediment, salinity and water-energy may be observed; depth is apparently significant only as it influences these. In the extinct algae, only a minority show clear taxonomic relationship to living algae, in palaeo-environmentsdeduced from independent evidence. Codiaceae and Dasycladales seem to have had environmental preferences like their living descendants, with preferredmicroenvironments in some genera.

A modified fission track technique has been used for datingbiotite flakes from crystalline rocks of Khammam district in Andhra Pradesh, India. The recorded fission track ages of 368±15 Ma to 616±20 Ma, with a mean of 475±90 Ma, correspond to the period of the Indian Ocean cycle. The data suggest an average cooling rate of about 0.6 °C per million years for the closing phase of this cycle.

A previously undescribed series of outcrops which lies nearBishop's Castle, 3.2 km S of the Longmynd-Shelve Area of Salop (Shropshire), displays a relationship between the Western Uriconian tuffs, WentnorSeries ashy turbidites (both Pre-Cambrian) and Ludlow Series siltstones. This throws further light on the structure of the Pontesford-Linley Disturbance, indicating that, in the vicinity of the outcrops, a component of its movement may have been post Ludlow in age.

The zonal pattern of metamorphism in the Scottish Highlandsis more complex than that suggested by Chinner. It has been disrupted by major tectonic dislocations and cannot be interpreted as a simple thermal anticline. Retrogression and inversion of zones seen in NW Scotland may resulteither from structural perturbation or the interference effects of superimposed metamorphism. A sinistral displacement of the Great Glen Fault still seems to match the metamorphic patterns in the opposing blocks, even if allowance is made for a major downthrow to the SE.