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Notes: Abstract Continental red beds are the host rocks of a characteristic style of mineralization which suggests a genetic link between red bed formation and ore formation. Samples of unmineralized and mineralized Triassic sediments from Central England have been studied sedimentologically, petrographically and geochemically with the aim of clarifying this link which may provide valuable guides for exploration. On the basis of sedimentological and petrographic observations it is suggested that these red beds were formed as a result of diagenetic alteration whereby detrital silicates and oxides are progressively dissolved and the iron released is deposited as hematite. A model for mineralization is proposed involving the release of trace metals from detrital minerals during diagenesis, their retention in saline interstitial solutions, migration to suitable sites of precipitation and deposition by reaction with trapped hydrocarbons or reduced sulphur.

Notes: Most activities might benefit from an independent review; but very little attention has been given to the review of research and development (R & D). The evolving scope of internal audit together with trends in R & D provide a more favourable climate for the internal audit of this industry of discovery (Walley, 1974, p. 191).This paper presents the results of a survey which was questionnaire based and completed by internal auditors, most of whom worked for industrial multinationals which are household names. They represented companies employing 0–61 m staff with a turnover of |SL12b p.a.; 75|X% of the respondent organizations were industrial concerns employing 0.56m with a turnover of |SL10.7b p.a., most of the remaining respondents being financial organizations. Forty-two per cent were under overseas control.By focusing on the practice and intentions of leading organizations with a record of progressive management, the results of the survey point a way which is likely to be followed more generally. As the internal audit departments were also large (29 auditors in each; 35 for the industrial departments) they were better placed to extend the scope of their work.

Notes: Abstract The Borgtinderne nepheline-sodalite syenite is one of the major intrusions in the Tertiary igneous province of East Greenland. The syenite magma, which was evolving towards an undersaturated peralkaline residuum, underwent extensive modification by incorporation of country rock basalt, resulting in the production of a variety of hybrid syenites. Major element variation in the hybrids is essentially linear. Break-up and mechanical incorporation of the basic material was aided by amphibolitisation and metasomatism of the basalt xenoliths.

Notes: Abstract The epizonal, Tertiary Lilloise layered intrusion (5–9 km diameter) has a well developed amphibolitised basalt aureole, several hundred metres wide. The sequence of main cumulate minerals is olivine, augite, plagioclase, amphibole (Ti-hornblende to hastingsite), with amphibole first appearing as an intercumulus mineral about 2000 m below the present top of the intrusion. The range of δD and δ18O values (SMOW) of amphiboles and biotites from early intercumulus, and cumulus minerals and late pegmatites is very narrow, -70 to -88‰ and +4.3 to 5.5‰ respectively. Amphiboles or whole rocks from the basaltic country rocks change from δD= -85‰ near the contact to -116 in the outer part of the aureole, and to -118 in the non-metamorphosed basalts up to 9km away. All basalts are depleted in 18O relative to “normal” values with the largest depletion (up to 2–3‰) in the outer part of the aureole. Meteoric water did not interact with either the magma or the hot plutonic rocks. This is in contrast to the results from most other plutonic complexes in the North Atlantic Tertiary igneous province (Skaergaard, Kangerdlugssuaq, Skye, etc.) many of which were similarly emplaced into basaltic country rocks. A meteoric-hydrothermal convective system was established in the basalts including the inner contact zone prior to the complete crystallisation of the Lilloise magma. The inner part of the aureole was finally modified by magmatic-hydrothermal fluids which evolved non explosively from the Lilloise magma. The meteoric-hydrothermal system in the outer part of the aureole, with integrated water/rock ratios of about 0.2 (atom % oxygen), did not collapse in on the hot pluton or inner contact metabasalts. Several factors may have reduced the permeability of the basalt country rocks. The emplacement of dykes prior to the Lilloise intrusion and possible associated weak hydrothermal activity could have restricted circulation of meteoric water; major fracture permeability was not generated during the quiet non-explosive crystallisation history of the Lilloise single magma pulse; metasomatism and alteration accompanying the magmatic-hydrothermal fluids may have reduced permeabilities in the inner aureole. Meteoric waters, however, did enter locally, at a very late stage, during low temperature serpentinisation of periodotite.