The application of sequence stratigraphic models to seismic data is restricted by the vertical and spatial resolution of the data. The fundamental stratigraphic unit of the sequence stratigraphic technique is the seismically distinguished ‘sequence’ although the concept of tectonically related ‘megasequences’ is useful. Basin stratigraphy is controlled to varying degrees by eustatic sea-level change (or base level in lakes), subsidence/uplift (tectonics) and sediment supply. Three main basin types, rift-, wrench-, and thrust-related basins, have distinctive gross stratigraphic architectures. Localized, tectonically controlled subsidence and uplift has a significant control on three-dimensional stratigraphic patterns.

New biostratigraphical analysis of the Humber Group sediments from the UK North Sea Central Graben, using integrated palynological and micropalaeontological zonation schemes, allows substage resolution and basin-wide discrimination of subunits of the Heather Formation/Kimmeridge Clay Formation, and associated sandstones. The integrated use of both zonation schemes is particularly important because thermally mature Humber Group sediments buried below 12 000 ft in the Central Graben cannot be dated consistently to substage level using palynology alone. Poor data and the undiagnostic log character of the mudstones and shallow marine sandstones have resulted in a simple lithological scheme being widely applied, with all sandstones assigned to the Fulmar Formation and mudstones to the Heather Formation and the Kimmeridge Clay Formation. Previous generalized usage of the Fulmar Formation for all Upper Jurassic shallow marine sandstones is inappropriate. The Upper Oxfordian Puffin Formation is present in the northern and western Central Graben. The largely Kimmeridgian Fulmar Formation is restricted to the south and east, and the coeval Ula Formation flanks the Jaeren High. These three units are all interpreted as syn-rift sandstones, locally sourced from uplifted and eroded fault block crests within and marginal to the Central Graben. Latest Kimmeridgian or younger shallow marine sandstones are largely confined to platform areas outside the graben, and can be related to regressive phases.

The identification and correlation of genetic sequences has significantly enhanced our understanding of the Late Jurassic stratigraphy in the Central North Sea. The integration of genetic sequences with an appreciation of the basinal mudrock stratigraphy, and the identification of depositional sequence boundaries provides a powerful tool to understand and potentially predict the distribution of subtle stratigraphic turbidite plays. The largely syn-rift Late Oxfordian-Kimmeridgian was deposited during a low frequency, second-order sea-level rise, culminating in the eudoxus condensed section. Deposition was dominated by shallow marine shelfal sandstones and offshore mudrocks. Sandy turbidites are rare. Whilst the requisite depositional slopes and deep water areas are likely to have existed, the effects of high frequency relative sea-level falls are likely to have been suppressed. As the second-order sea-level rise accelerated towards the eudoxus condensed section, the supply of sand into the basin was reduced such that the potential for turbidite deposits was minimal. The largely post-rift Kimmeridgian-Volgian section is dominated by basinal mudrocks. However, regionally correlatable ‘hot’ and ‘cool’ units provide information on sediment flux into the basin which may be linked to relative sea-level changes on the basin margin, with cool units interpreted to be the product of enhanced depositional rates during lowstand. Turbidites commonly occur within the ‘cool’ mudrock units. A Middle Volgian ‘cool’ unit is likely to represent a second-order sea-level fall, within which are composite turbidite packages which are considered to be the product of higher frequency lowstands (lowstand sequence set).

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There is an increasing tendency for administrators and government to expect both the health services and the education service to 'show results' for the investment of public money in them. One response to this has been the growing commitment to 'health promotion', where measurable objectives may be set in terms of desired behaviour (stopping smoking, breast self-examination, child immunisation etc) and where evaluation can be made on the evidence of statistical improvement. Health workers use the term 'promotion' in a variety of ways which seem to be as confusing to them as they are to their clients --the general public. Since successful promotion is likely to depend on the 'hard sell' (and since the methodology and aims of this may be incompatible with those of health education) this paper looks at some of the questions which the customer might wish to ask the salesman before deciding whether or not to buy.