Image analysis is rapidly becoming an integral part of scanning electron microscopy. A number of analogue and digital image analysis systems of varying sophistication are now commercially available for the SEM. This paper illustrates how one such relatively simple system, the IMAS image analyser manufactured by Cambridge Technology, can be used to obtain rapid quantitative estimates of porosity and mineral abundance in backscattered electron images of polished rock sections.

Neogene and Lower Pleistocene stratigraphy in the Southern North Sea has been investigated in four I.G.S. boreholes between East Anglia and the Netherlands. The foraminifera of the Red Crag Formation in Borehole 81/51 are closely similar to Upper Pliocene assemblages in Holland. The overlying succession is clearly punctuated by unconformities in seismic profiles, separating four early Pleistocene formations in the boreholes, and indicating intervals of significant stratigraphic hiatus offshore. The Westkapelle Ground and Smith's Knoll Formations correlate with Thurnian and Antian Stage deposits in East Anglia. Pollen spectra in the Winterton Shoal and Yarmouth Roads Formations are similar to Baventian and Bramertonian assemblages in Britain. The autochthonous marine and allochthonous terrestrial microfauna and flora provide conflicting evidence of early Pleistocene palaeoclimate. The dinoflagellate cysts and foraminifera indicate that each formation was deposited in a warm temperate neritic environment. The pollen record, containing evidence of fluctuation between boreal and mixed coniferous–deciduous regional forest cover, suggests alternation between cool and warm temperate palaeoclimate.

On the basis of previous work in Northern England and in Southern Scotland the Pusgillian Stage is in turn related to the stratigraphical ranges of selected trilobite species and to the standard graptolite zonal scheme. Thus characterized it can be recognized in rocks of ‘shelly’ facies at localities in the northwest, southeast and south-central Berwyn Hills of North Wales and possibly in the Llandeilo area of South Wales, but does not seem likely to be developed in any rocks of graptolitic facies in Wales.

The present work describes the quartz geodes (cauliflower-like) that appear in a specific level of the Late Cretaceous (north of Burgos). Due to their special characteristics, principally anhydrite relicts and spherulitic quartz (length-slow chalcedony), they are considered as pseudomorphs of anhydrite nodules, formed during early diagenesis. At the same level compact chert nodules sporadically appear, presenting a considerable amount of sponge spicules with fibrous texture (length-fast chalcedony). The silicification of the anhydrite nodules took place before total compaction and cementation of the sediment. The source of silica is principally biogenic (sponge spicules). We offer a hypothesis to explain the formation of the anhydrite nodules since there is no link between the depositional environment and the existence in itself of anhydrite nodules. Indirectly it is possible to see the effects of an arid climate, which have not been recorded in the lithologic column here described.

Nautiloids from the shallow water Ordovician carbonates of Central and Southern Thailand can be grouped into five broad assemblages. 1. The Middle Ibexian fauna of indeterminate endocerids from Tarutao Island. 2. Hardmanoceras chrysanthimum (Kobayashi) of the Upper Ibexian age strata on Tarutao Island. 3. The Upper Ibexian Manchuroceras nakamense sp.nov. from Ron Phibum, Southern Thailand. 4. Wutinoceras sp., Chaohuceras? sp. of Lower to Middle Whiterockian age strata from Satun Province. 5. Wutinoceras sp., Armenoceras chediforme Kobayashi and Georgina sp. of Lower-Middle Whiterockian age strata from Kanchanaburi, Central Thailand. All of these genera occur in Australia and China.

The I.U.G.S. Subcommission on Carboniferous Stratigraphy recommends that the base of the Westphalian D is best recognized using plant macrofossils. In Britain, however, South Wales is the only coalfield where the distribution of the plants is sufficiently well known for them to be used to locate this boundary. Elsewhere in Britain other criteria have been used, particularly non-marine bivalves and plant microfossils, but these must be regarded with considerable caution.

The taxonomy of the Middle Jurassic ammonite genus Spiroceras Quenstedt, 1856, is critically assessed. It is found that the genus was originally proposed conditionally without any included species, and the type species is Spiroceras bifurcatum Hyatt, 1900, by subsequent monotypy. A neotype is now designated for that species, because Hyatt's figured holotype is lost.